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This document explores the molecular mechanisms of gene function, including the structure and function of genes, and the process of translation. It details the genetic code and its role in protein synthesis. This document is a good resource for advanced study in molecular biology and genetics.

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4 genis moqmedebis molekuluri meqanizmebi 91 Tavi a T g c T a g g T genis moqmedebis molekuluri meqanizmebi Sesavalo makodi...

4 genis moqmedebis molekuluri meqanizmebi 91 Tavi a T g c T a g g T genis moqmedebis molekuluri meqanizmebi Sesavalo makodirebeli genebi (romlebic genetikuri kodi ganapirobeben cilis, ribosomul da – dnm-s nukleotidur TanamimdevrobaTa pirveladi – satransporto rnm-s sinTezs) gani- `tripleturi kodi~ – dnm-s nukleotidur TanamimdevrobaTa meoreuli – sazRvreba ≈4·104 b raodenobiT. `qromatinis kodi~ `adamianis genomis proeqtis~ mo- – dnm-s nukleotidur TanamimdevrobaTa mesameuli – `qromatinis kondensaciis kodi~ nacemebiT genomis makodirebeli nawili genomika - mecniereba genomis Sesaxeb _ egzonebi (Gilbert, 1978) warmoadgens genis centruli Teoria totaluri dnm-s mxolod 1%-s, genomis genTa organizaciis principi prokariotebSi aramakodirebeli nawili _ intronebi genTa organizaciis principi evkariotebSi _ 24%-s, genomis danarCeni dnm _ 75%- – soliteri genebi s. es ukanaskneli cnobilia, rogorc – dispersuli genebis ojaxebi genTaSoris ubnebSi lokalizebuli – fsevdogenebi – genis ojaxis tandemuri wyoba Tanamimdevrobebi (Venter et al., 2001), e.w. – moduluri genebi `Warbi dnm~, `arafunqcionirebadi dnm~, transkrifcia `gaCumebuli dnm~. genis struqturuli nawili Warbi dnm-s arseboba warmoadgens alternatiuli splaisingi evkariotTa ujredebis ZiriTad Tavi- ribosoma translacia seburebas, rac maT ganasxvavebs proka- daskvna riotuli organizmebisagan. literatura Warbi dnm jer kidev ar aris srul- saZiebo internetSi yofilad Seswavlili. fiqroben, rom: kiTxvebi genetikuri terminebi 1. misi meSveobiT xorcieldeba Za- amocanebi lian grZeli dnm-s molekulis mowesrigebuli Calageba patara zomis birTvSi; Sesavali 2. iqmneba genTa funqcionirebis kont- rolis saSualeba. dnm-s Calagebis evkariotul, maT Soris adamianis qro- mdgomareobis (kondensirebuli, de- mosomebis mTel sigrZeze ganTavsebulia kondensirebuli) xasiaTi moqmedebs erTaderTi uwyveti dnm-s molekula. masSi genomis zogierT ubanSi arsebul adenin-Timinisa da guanin-citozinis genTa aqtivobaze. wyvilebis Semcveloba araTanabrad aris gansazRvruli Tanamimdevroba ge- ganawilebuli. adamianis genomis zoma nomSi warmodgenilia ramdenime aslis Seesabameba 3·109 nukleotidur wyvils, saxiT da maT uwodeben ganmeorebad Tana- anu 3 miliard bass, 3 milion kb (kilobasi), mimdevrobebs. Tu movaxdenT evkariotTa anu 3000 mb (megabasi). dnm-s denaturacias, xolo Semdgom 92 Tavi 4 adamianis genetika SevqmniT pirobebs misi renaturaciisaTvis, (tripleti). marTlac, rom aviRoT ori anu reasociaciisaTvis (denaturirebuli nukleotidi sxvadasxva kombinaciiT, dnm-s reasociaciis kinetikis Seswavlisas), aRmoCndeba, rom maTi raodenoba aris 16 aRmoCndeba, rom evkariotTa genomSi (42), xolo sami nukleotiduri kombinaciis nukleotiduri Tanamimdevrobebi xa- SemTxvevaSi - 64 (43). azotovani fuZeebis siaTdeba sxvadasxva xarisxis ganmeo- 64 kombinacia savsebiT uzrunvelyofs 20 rebadobiT. arsebobs evkariotuli ge- aminomJavas kodirebas. nomis Semdegi fraqciebi: kodis arseboba f. krikma (Krick, unikaluri, rodesac nukleotiduri 1961) eqsperimentulad daamtkica prof- Tanamimdevroba warmodgenilia erT as- lavinis saSualebiT inducirebuli lad. saSualo sixSiris anu zomieri gan- pirdapiri da ukumutaciebis ganxilvisas meorebadobebi, rodesac nukleotiduri T4 baqteriofagis magaliTze. cnobilia, Tanamimdevroba meordeba aTeul da rom proflavini iwvevs dnm-s molekulaSi aseuljer (adamianSi Seadgens genomis mutaciebis induqcias. amasTan dakavSi- 8%-s) da maRali sixSiris ganmeorebado- rebiT saintereso iyo im faqtis dadgena, bebi, rodesac ganmeorebadobebis ricxvi rom erTi mutaciuri cvalebadoba milions aRwevs (adamianSi Seadgens SeiZleba Seexos erT aminomJavas. namgli- genomis 15%) (am cifrebma, romlebic seburujreduli anemiis SemTxvevaSi sxvadasxva avtorTa monacemebSi hemoglobinis molekulaSi, romelic gansxvavebulia, SeiZleba momavalSic ga- Sedgeba daaxloebiT 300 aminomJavasagan, nicados cvalebadoba). xdeba mxolod erTi aminomJavas _ glutaminmJavas Secvla valiniT. dnm-s genetikuri funqcia dakavSi- rebulia dnm-s nukleotidur Tanamimdev- amave dros aRmoCnda, rom genetikuri robebTan. maTi organizaciuli erTeulia kodi gadaufaravia, radgan erTsa da imave - kodi, romelic warmoadgens instruqtaJs nukleotids ar SeuZlia ori tripletis specifikuri molekulebis urTierTqmedebis SemadgenlobaSi Sesvla. procesTa ganxorcielebisaTvis. 1961 wels m. nirenbergma da j.mateim (Nirenberg and Mattey, 1961) araujredul sistemaSi daadastures, rom uracilis genetikuri kodi erTnairi nukleotidebiT Sedgenili ri- bonukleinmJavas sinTezirebuli mole- kulebi akodirebs erT aminomJavas _ dnm-s nukleotidur fenilalaninsa da rom Sesabamisad am TanamimdevrobaTa pirveladi _ aminomJavas makodirebeli tripleti `tripleturi kodi~ aris uracili - uuu. axali meTodebis gamoyenebiT oCoam TanaavtorebTan erTad genetikuri kodi aRmoCenilia 1961 wels. (Ochoa, 1966) gansazRvra tripletebi dnm-sa da cilebs Soris urTierTkavSiri 20-ve aminomJavasaTvis. dadginda, rom ganisazRvreba imiT, rom cilis spe- arsebobs Sesabamisoba nukleotidur cifikuri struqtura ganpirobebulia jaWvSi kodonTa mwyobr ganawilebasa genetikuri informaciiT, romelic Cawe- da polipeptidSi sinTezirebul rilia dnm-s molekulaSi. 1954 wels g. aminomJavaTa mwyobr ganawilebas Soris. gamovma (Gamow, 1954) gamoTqva varaudi, am movlenas 1963 wels f. krikma (Krick, rom 4 nukleotidis (a, T, g, c) garkveuli 1963) kolinearuloba uwoda. Tanamimdevroba dnm-s molekulaSi aris is kodi, romlis daxmarebiTac Caiwereba 1966 wels g. qoranas (Khorana, garkveul aminomJavaTa Tanamimdevroba 1966) da sxvaTa Sromebis safuZvelze cilis polipeptidur jaWvSi (cilebi gaSifrul iqna yvela kodonis Si- Seicaven 20 ZiriTad aminomJavas). 1961 wels naarsi. sxvadasxva kodonis ricxvi f. krikma (Krick, 1961) gamoTqva mosazreba, sami nukleotidis kombinaciiT unda rom cilaSi erT aminomJavas Seesabameba yofiliyo -^64. Tu yvela (64) kodoni sami azotovani fuZis Tanamimdevroba monawileobs cilis sinTezis procesSi, genis moqmedebis molekuluri meqanizmebi 93 unda velodoT, rom erT aminomJavas 8. sami terminatori anu nonsens kodoni SeuZlia Sediodes polipeptidis Semad- (uaa, uag, uga) gansazRvravs cilis genlobaSi sxvadasxva kodonis signalis sinTezis damTavrebas. gamo. es azri swori aRmoCnda. genetikur kods aqvs Secvladobis unari, rac imaSi ujredis reaqciis Semguebluri gamoixateba, rom calkeuli aminomJava xasiaTi da ontogenezis periodSi ar- SeiZleba dakavSirebulia ramdenime sebuli metaboluri kanonzomierebani tipis kodonTan. mag., aminomJava leicini damokidebulia sxvadasxva genis di- kodirdeba sxvadasxva kodoniT (uua, ferencialur aqtivobaze. aman ganapiroba uug, cuu, cuc, cua, cug). amave dros genTa moqmedebis regulaciis meqanizmis yvela kodons ar SeuZlia aminomJavas Seqmna, rac erT-erTi mniSvnelovani rgo- kodireba. makodirebelma kodonma (61) lia genetikuri evoluciisa da indi- miiRo azrobrivi kodonebis saxelwodeba. vidualuri ganviTarebis procesSi. sami kodoni _ uua, uag, uga ar iRebs am SemTxvevaSi dnm-s pirveladi monawileobas cilis sinTezSi da maT Tanamimdevrobebis kodi gadadis cito- ewodaT uazro - nonsens”tripletebi. isini plazmaSi ribosomebze specifikur i-rnms gaCerebis signalis rols asruleben molekulis transkrifciis Sedegad. (uua - oxra, uag - amberi da uga - opali) ribosomebze i-rnm urTierTqmedebs (sur. 4.1). sxvadasxva satr-rnm-s molekulasTan, romelsac aqvs specifikuri tripleturi genetikuri kodis damaxasiaTebeli nukleotidi. sat-rnm-s TiToeuli mo- Taviseburebaa misi universaloba. dawye- lekula specifikuria erT aminomJavasa buli virusidan, adamianebis CaTvliT da i-rnms Sesabamisi kodonis mimarT. yvela organuli formis erTi da igive sat-rnm-s molekula Tavis funqcias aminomJava ganisazRvreba erTi da imave axorcielebs ferment aminoacilsinTe- kodoniT. rogorc iyo aRniSnuli, tazas saSualebiT, rodesac masTan genebs, romlebic akodireben cilebis dakavSirebulia Sesabamisi aminomJava. struqturebs, ewodeba struqturuli genebi. aminomJava da sat-rnm urTierTTan kavSirs axorcieleben kovalenturi bme- kodis zogadi Taviseburebani dad- biT, romlis drosac ixarjeba erTi genili iyo genetikuri meTodebiT. aR- molekula atf. amis Semdgom sat-rnm moCnda, rom: Tavisi antikodonebiT ukavSirdeba 1. genetikuri kodi universaluria; i-rnms kodonebs ribosomebSi da qmnis polipeptidur jaWvs. 2. kodi tripleturia (kodirebs sami nukleotidiT); 3. kodi gadauxuravia, ar Seicavs gam- dnm-s nukleotidur yof niSnebs; TanamimdevrobaTa meoreuli _ 4. axasiaTebs kolinearuloba; `qromatinis kodi~ 5. Tavisi bunebiT cvladia (yvela ami- 1980 wels aRmoaCines trifonovma da su- nomJavas meTioninis da triftofanis zmanma (Trifonov and Sussman, 1980). maT garda, aqvs erTze meti kodoni); daadgines, rom adeninis (aa) nukleotiduri wyvilebi 10.5 periodulobiT gvxvdeba 6. sami nukleotididan upiratesi mniS- dnm-s nukleotidTa TanamimdevrobaSi, vneloba aqvs pirvel ors, mesame igi urTierTqmedebs histonur oqta- eqvemdebareba cvalebadobas; merebTan da exveva nukleosomas. 10.5 7. translaciis dros mniSvneloba n.s. perioduloba korelirebs dnm-s eniWeba aug da gug-s, romelsac spiralis xveulebis periodulobasTan _ uwodeben sainiciacio kodonebs. eseni spiraluri dnm-s meoreul struqturaSi. gansazRvraven genis produqtis sin- B dnm-saTvis nukleotidTa ricxvi erT Tezis dawyebas; xveulSi varirebs 10.0_10.1 n.T-mde. B _ spiralis nukleotidTa fizikurma 94 Tavi 4 adamianis genetika suraTi 4.1 dnm-s ormagi g Tg T cg g a a spirali T g cI I a cI g g I I g cI g g I c I T TI g g I a 3' c aI cI I g c I a I c I c T c c I I c 5' I I c c I I I c I 5' g c T g g a g 3' dnm-s matriculi 3' 5' Zafi c T g g T a c c c g a g g T a g c c g c g T c g T T c g I I I I I I I I I I I I I I I I I I I I I I I I I I I I transkrifcia g a c c a u g g g c u c c a u c g g c g c a g c a a g c i-rnm 5' 3' 1 2 3 4 5 6 7 8 translacia cila pirveli mesame mdgomareoba meore mdgomareoba mdgomareoba u c a g (5' -'bolo) (3'’- bolo) u fen ser Tir cis u fen ser Tir cis c lei ser * 1 * 2 a lei ser 3 trip g c lei pro his arg u lei pro his arg c lei pro glm arg a lei pro glm arg g a ile tre asm ser u ile tre asm ser c ile tre liz arg a meT tre liz arg g g val ala asp gli u val ala asp gli c val ala glu gli a val ala glu gli g * uazro kodonebi:1 - oxra; 2 - opali; 3 - amberi tri pleturi kodi 1959 wels ribonukleinis mJavas biolo- 1968 wels genetikuri kodis aRmoCenisa giuri sinTezis meqanizmebis dadgenisaT- da cilis sinTezSi misi funqciis in- vis s. oCoas (S.Ochoa) mieniWa nobelis terpretaciisaTvis r. holis (R. Holley), premia. h.qoranas (Khorana) da m.nirenbergs (M.Nirenberg) mieniWaT nobelis premia. genis moqmedebis molekuluri meqanizmebi 95 analizma gviCvena, rom adeninsa da adenins mesame: rekombinaciuli kodi. cnobilia, Soris iqmneba solismagvari kuTxe, rac rom imunoglobulinebis genebis onto- Semdgom ganapirobebs spiralis gada- genezuri eqspresiis amoqmedeba xdeba Runvas. aqedan gamomdinare, daaskvnes, specifikuri dnm-s TanamimdevrobaTa aq- rom adeninis nukleotidTa ganlagebas tiuri rekombinaciuli procesebiT. aq- gadamwyveti mniSvneloba aqvs histonuri tiuri rekombinaciuli procesebi SeiZ- oqtameruli kompleqsis irgvliv spi- leba arsebobdes adamianTa genomSic. ralis daxvevis mimarTulebis kodire- bisaTvis da amitom am kods uwodes qro- tandemurad ganmeorebadi Tana- matinis kodi. mimdevrobebi genomSi ganawilebulia sxvadasxvagvarad: isini ganlagebulia did tandemur blokebad, romlebic dnm-s nukleotidur Tanamimdevro- xasiaTdeba sxvadasxva TanamimdevrobaTa baTa mesameuli _ `qromatinis ganmeorebadobebis rigiT, romlis sigrZe SeiZleba iyos erTi an ramdenime aTasi kondensaciis kodi~ nukleotidi (I tipi); mcired cvladi qromosomaTa nukleohistonuri Zafi tandemuri ganmeorebadi blokebi SeiZ- dakavSirebulia mJave (arahistonur) leba erT blokad lokalizdes an mimoi- cilebTan. arahistonur cilebTan kav- fantos genomSi da Seicavdes monaTesave Siri qmnis mokle RerZul-xazobriv TanamimdevrobaTa elementebs (II tipi). struqturas da Runavs supernukleotidur Zafs maryuJebad. maryuJebis Calageba SesaZlebeli xdeba maTi CagrexviT Tavis RerZis garSemo, ris Sedegad formirdeba genomika _ mecniereba genomis 50-60 nm-s diametris Zafebi. rogorc Sesaxeb aRiniSna (Vogt, 1990), arahistonuri ci- lebi Ca++ ionebis moqmedebisas da genTa im raodenobas, romelic gansazRv- fosforilirebis Sedegad iwvevs dnm-s ravs niSnis fenotipur gamovlenas, lokusspecifikur daxvevas da lo- ewodeba genotipi, xolo genomi warmoad- kusspecifikuri qromatinuli struq- gens dnm-s raodenobas, romelic moTav- turis kodirebas birTvSi, rasac vogtma sebulia aRniSnuli saxeobis qromosomaTa qromatinis kondensaciis kodi”uwoda. haploidur nakrebSi. qromatinis kondensaciis kodi ar genetikis nawils, romelic Sei- unda SemoizRudos birTvSi qromosomebis swavlis cocxal organizmTa mTlian organizaciis struqturuli roliT. genomebs, ewodeba genomika. genomikis SeiZleba hqondes potenciurad kodirebis kvlevis mizans warmoadgens ama samnairi funqcia. Tu im organizmis ujredebSi dnm- pirveli: cilis makodirebeli genebis s nukleotidur TanamimdevrobaTa promotorul ubnebSi sxvadasxva martiv Seswavla. adamianis genomis” proeqtSi TanamimdevrobaTa arseboba miuTiTebs, mecnierebi cdilobdnen gadaeWraT xuTi rom lokusspecifikur ganmeorebad ZiriTadi problema: struqturas SeuZlia miiRos monawileoba mosazRvre cilis makodirebeli 1. detaluri genetikuri rukebis Sedgena, sadac miTiTebuli iqneboda genebi, dnm-s transkrifciis regulaciaSi. es daSorebuli erTmaneTisagan ara SeiZleba moxdes qsovilspecifikuri an umetes 2 milioni nukleotiduri ganviTarebad safexurebriv-specifikuri TanamimdevrobiT; gziT. am kods SeiZleba ewodos genis eqspresiis kodi. 2. TiToeuli qromosomis dnm-s fizi- meore: replikaciis saitebi moce- kuri rukebis Sedgena; mulia ganmeorebadi dnm-s n.T. struq- 3. mTliani genomis rukis Sedge- turaSi, romelic warmodgenilia, ro- na calkeuli dnm-s klonebis da- gorc replikaciuri kodi. xasiaTebiT; 96 Tavi 4 adamianis genetika 4. 2004 wlisaTvis dasrulebuli unda aramed nukleotidTa wyvili, romlebic yofiliyo dnm-s sruli sekvenireba; eqvemdebarebodnen rogorc mutaciebs, ise rekombinacias. 5. adamianis yvela genis nukleotiduri Tanamimdevrobebis rukaze aRniSvna. pirvelad genis dayofadoba (genis centruli Teoria) daasabuTes n. dubininma adamianis genomis”proeqtis Sesasru- da a. serebrovskim (Дубинин и Серебровский, leblad gamoyenebuli iyo genuri inJi- 1929) drozofilaze eqsperimentis, lokus neriis Tanamedrove meTodebi da mo- achaete-scute-s mravlobiT alelTa seriis nacemebis damuSavebis kompiuteruli gamokvlevisas. alelTa achaete-scute ka- teqnologiebi. nonzomier komplementaciaze (niSnis genomis proeqtis praqtikuli mxa- nawilobriv an mTlianad gamoxatvis ris Sefasebisas pirvel rigSi unda alelTa urTierTdominirebis movlena) aRiniSnos im genebis analizi, romelTa dayrdnobiT wamoayenes hipoTeza genis mutaciebi iwveven daavadebaTa gaCenas. rTuli Semadgenlobis Sesaxeb. miRebuli mag. adamianis ATM genis mutacia iwvevs kanonzomieri monacemebis Sesabamisad ataqsia-teleangieqtazias. Seadgines genis Semadgenlobis kom- plementaciis ruka. aCvenes, rom genis ukve 1996 wlisaTvis cnobili iyo nawilebi _ centrebi dalagebulia genSi mutaciebi 50 genSi. xazobrivad. es dadginda mutaciuri analizis safuZvelze. miRebul iqna Sedegebi, rom krosingoveri mimdinareobs genis centruli Teoria genSi, igi aSorebs erTmaneTs mutaciur centrebs, romlebsac genSi sxvadasxva adgili uWiravs. am faqtebze dayrdnobiT s. morganis (Morgan) mier memkvidreobis genis centrulma Teoriam wamoayena qromosomuli Teoriis Camoyalibebis principulad axali monacemebi. aRmoCnda, Semdeg, abstraqtuli warmodgena gen- rom: ze (termini geni Semoitana v. iohan senma (Johannsen, 1909) Seicvala konkre- 1. geni iyofa rTul kompleqsur war- tuli SinaarsiT. damtkicda, rom or- monaqmnad, romelic Seicavs xazob- ganizmis yvela niSani ganisazRvreba rivad ganlagebul elementarul memkvidreobiTobis diskretuli ele- erTeulebs (geni bazigenis saxiT mentaruli erTeuliT _ geniT. geni Sedgeba transgenebisagan); qro mosomaSi ikavebs gansazRvrul ad- 2. genis farglebSi mis nawilebs gils _ lokuss da warmoadgens re- SeuZliaT TviTonve ganicadon muta- kombinaciis, mutaciisa da funqciis cia, romelic genis sxvadasxva uban- zRvrul erTeuls. Semdgom, meTodTa Si sxvadasxva siCqariT mimdinareobs. daxvewis Sedegad da molekulur doneze zogierTi maTgani maqsimaluri mu- gamokvlevaTa Catarebam cxadyo, rom tabelobis gamo warmoadgens e.w. genis gansazRvrebas Seesabameba mxolod cxel ubnebs; erTi kriteriumi. kerZod, geni warmoad- 3. geni ar aris rekombinaciis erTeuli, gens funqciis erTeuls, romelic ako- radgan krosingoveri mimdinareobs direbs polipeptidur molekulas an genSi; nukleinmJavebs. gadafarvadi genebis 4. geni, aqvs ra specifikuri funqcia, aRmoCenis Semdeg naTeli gaxda, rom amave dros funqcionaluri Tval- genetikuri masalis erT diskretul sazrisiTac warmoadgens rTul sis- erTeuls SeuZlia ori an meti niSnis temas, radgan misi moqmedeba mTlianad kodireba. rac Seexeba gens, rogorc ganpirobebulia sakuTari centrebis mutaciisa da rekombinaciis erTeuls, kompleqsuri moqmedebiT. es Sexeduleba xelaxla gadaisinja, radgan aRmoCenil iqna genis nawilebad dayofadoba krosingoveris Sedegad, xolo erTeulad ganixileba ara geni, genis moqmedebis molekuluri meqanizmebi 97 4.1. genuri Terapia da pirovnebis identifikacia 1990 wels amerikaSi Catarda klinikur praqtikaSi pirveli warmatebuli eqsperimenti genoTerapiaSi. bavSvi daavadebuli iyo mZime kombinirebuli imunodeficitiT, dakavSirebuli adenozindezaminazas masinTezirebeli genis mutaciasTan. avadmyofi bavSvisagan miRebuli sisxlis T-limfocitebis kulturebSi, retrovirusis veqtoris meSveobiT SehyavdaT adenozindezaminazas masinTezirebeli dauzianebeli geni da ujredebs abrunebdnen kvlav bavSvis organizmSi. dauzianebelma genma daiwyo eqspresia. bavSvi ganikurna (sur. 4.2). suraTi 4.2 plazmida adamianis normaluri adenozindezaminazas (ada) geniT retrovirusi T ujredebi izolire- klonirebuli ada buli imunodeficitis CarTuli virusSi mqone avadmyofidan normalur ujreds retrovirusi ada-Ti ubruneben Sehyavs bavSvs ujredebSi ujredebi izrdebian kulturaSi aqtiuri ada geniT adenozindezaminazas masinTezirebeli dauzianebeli genis eqspresia imunodeficitiT daavadebis dros (Янковский, 1999) avadmyofobaTa meore jgufi, romelic genetikuri inJineriis meTodebis gamoyenebiT warmoadgens karg perspeqtivas gankurnebisaTvis, aris lizosomuri daavadebebi. sadReisod transgenezis saSualebiT gankurnebas eqvemdebareba adamianis aTamde daavadeba. genuri inJineriis meTodebiT samedicino praqtikaSi dainerga sadiagnostiko 200 axali preparati. pirovnebis amosacnobad da naTesaobis dasadgenad gamoiyeneba polimerazuli jaWvuri reaqciis meTodi. sinjis saxiT saanalizod sakmarisia dnm-s sakmaod mcire odenoba, ramdenime pikogrami. genetikuri naTesaobis dasadgenad gamoiyeneba genebi, romlebsac gaaCniaT mravlobiTi alelebi. am SemTxvevaSi TiToeuli alelis dnm gansxvavdeba erTimeorisagan sigrZiT. magaliTad, adamianis geni THOI Seicavs dinukleotidTa (citozin-adenini) mravaljer ganmeorebad Tanamimdevrobebs. arsebobs am genis 5 aleli, romelic Seicavs am dinukleotidis 5-dan 10-mde asls: (CA)5, (CA)6, (CA)7,.... (CA)10. 98 Tavi 4 adamianis genetika isini advilad ganirCevian fragmentTa sigrZiT, romelic mJRavndeba gelSi eleqtro- forezis Semdgom. F eleqtroforegramaze (sur. 4.3) kargad SeimCneva heterozigotebSi ori fraqcia, xolo homozigotebSi – erTi. bavSvis erTi fragmenti sididiT Seesabameba dedis erT-erT fragments, xolo meore – mamis erT-erT fragments. Tu or individSi ar mJRavndeba erTnairi zolebi, am SemTxvevaSi maTi naTesaoba ar dasturdeba, xolo Tu msga- vsi zolebi aris, maSin maTi naTesauri kavSiri realuria. suraTze Cven vxedavT, rom merve individi (romelic mamrobiTi sqesisaa), adre Catarebuli analizis Sedegad aris (CA)6 da (CA)9 alelis matarebeli. es alelebi ar gaaCniaT me-2, me-3, me-4, me-5, me-6 da me-7 individs. Sesabamisad, merve individi ar SeiZleba iyos maTi mama, radgan Svilebi unda atarebdnen mSoblis romelime alels. amave dros merve individi SesaZlebelia iyos an mama an Svili I-is an me-9 individis. ojaxis wevrTa damokidebulebebis Sesaswavlad xSirad iyeneben mitoqondriuli dnm-s molekulur markerebs. mitoqondriuli dnm-is Tanamimdevroba identuria dediseuli Stos matarebeli pirovnebebisaTvis, radgan ganayofierebis dros spermatozoidis citoplazma kvercxujredSi ver aRwevs. am saSualebebis gaTvaliswinebiT moaxdines ekaterinburgSi dasaflavebul imperator nikoloz II ojaxis wevrTa amocnoba. Seiswavleboda mit-dnm-s variabeluri ubani (d-maryuJis), romelic gamoyofili iyo Zvlis narCenebisagan. miRebul Sedegebs adarebdnen amJamad cocxal edinburgis hercog princ filipis mitoqondriul dnm-s Tanamimdevrobas (sur. 4.4). mit-dnm-s Tanamimdevroba princ filipsa da 4-7 individTa Zvlis narCenebSi identuri aRmoCnda. suraTi 4.3 sxvadasxva individTa dnm-s sinjebi dawyeba ganmeorebadi monomerebis 1 2 3 4 5 6 7 8 9 raodenoba 10 - 9- 8- 7- 6- amocnobili alelebi 9;10 8;10 7;10 8;10 7;8 8;10 8;8 6;9 6;6 ojaxuri jgufi lokus THOI aleluri mdgomareobis analizi (Янковский, 1999) genis moqmedebis molekuluri meqanizmebi 99 suraTi 4.4 dedofali princesa alisa - aleqsandra dedofal viqtorias qaliSvili mefe nikoloz II princi filipi dedofal aleqsandras genealogiuri xe (Янковский, 1999) febad-klasterebad. klasterSi gaer- genTa organizaciis principi Tianebuli genebi akodireben erTi prokariotebSi bisinTezuri gzis fermentebs da transkribireben saerTo i-rnm-s mole- kulas. aseTi i-rnm iwodeba policis- genebi, maTi moqmedebis gaTvaliswinebiT, tronul i-rnm-ad. struqturul genTa SeiZleba daiyos or jgufad: jgufi prokariotebSi kontrolirdeba 1. genebi, romlebic akodireben ci- erTi maregulirebeli ubniT, romelsac lebs aucilebeli struqturuli da uwodeben operons (Miller and Reznikoff, 1988). fermentuli funqciis sawarmoeblad. operonis tipis organizacia saSualebas maT struqturul genebs uwodeben aZlevs baqteriebs swrafad gadarTon da metabolizmi erTi substratidan meoreze. 2. genebi, romlebic akodireben ci- aucilebeli substratis monawileobis lebsa da patara rnm-s moleku- gareSe baqteria ar asinTezirebs gar- lebs genTa transkrifciis da qro- kveuli metaboluri saxis fermentebs. mosomaTa replikaciis procesebis zogierTi baqteriis gens gaaCnia indi- regulirebisaTvis. maT regulato- vidualuri transkrifciis unari. maT rul genebs uwodeben. i-rnm-s uwodeben monocistronuls. pro- regulatoruli genebis mier kariotebSi SesaZlebelia genTa Soris kodirebuli cilebi Tavisuflad ubnebis arseboba, romelsac speiserebs difundireben da naxuloben Sesatyvis uwodeben. genebs maTi aqtivirebisaTvis, aseTi klasteruli organizaciis maga- tipis urTierTqmedebas uwodeben trans- liTs warmoadgens E.coli-s laqtozis geni, regulacias. transregulatorul cilas romelic substratis moqmedebisas ganic- SeuZlia Sesabamisi genis an poziti- dis induqcias an represias. uri regulacia, Tu urTierTqmedebis Sedegad irTveba genis eqspresia, an nega- 1961 wels f. jakobma da J. monom tiuri, Tu regulirebadi geni cilasTan (Jacob and Mono, 1961) E.coli-Si laqtozis urTierTqmedebis Sedegad ar iwyebs SeTvisebis ganmapirobebeli lokusis eqspresias. im SemTxvevaSi, Tu regulatori Seswavlisas daamtkices cistronebis cila moTavsebulia regulirebad gen- blokis organizebuli regulacia. es Ta nukleotiduri Tanamimdevrobis max- movlena mdgomareobs imaSi, rom gar- loblad, aseT urTierTkavSirs uwo- kveul genTa aqtiuroba, romlebic deben cis-regulacias. akodireben cilis, satransporto da prokariotTa genomis mniSvnelovani ribosomuli rnm-s sinTezs (struqturuli Taviseburebaa genebis gaerTianeba jgu- genebi), damokidebulia funqciuri 100 Tavi 4 adamianis genetika (regulatoruli) genis moqmedebaze 4. amis Semdgom ganlagebulia struq- (sur. 4.5). am genetikuri regulaciis turuli genebi (struqturuli erTeuls laqtozis operoni uwodes. genebis sigrZe Seadgens 6000 operonis SemadgenlobaSi arsebul nukleotidur wyvils), romlebic genTa kompleqsis detalurma analizma awarmoeben _ ß-galaqtozidazas, ß- daadgina masSi ori ZiriTadi ubnis galaqto-zidpermiazas da galaqto- arseboba: erTi, romelic moicavs regu- zidtrans acetilazas sinTezs. latorul genebs (erTi regulatoruli am fermentTa monawileobiT xor- geni (sur. 4.14. operonis Semadgenlobis cieldeba baqteriebis mier laqtozis gareT aris) da meore _ Seicavs struq- SeTviseba. transkrifcia Cerdeba A turul genebs. struqturuli genis transkrifciis laqtozuri operonis (Lac-operoni) damTavrebis Semdgom terminatori ko- funqciur nawilSi Sedis: donis arsebobis gamo, romelic aCerebs rnm-polimerazis gadaadgilebas. trans- 1. geni promotori, romelic Sedgeba kribirebuli r+, Z, Y, A genebi, romelTa 87 nukleotiduri wyvilisagan da Soris rnm polimeraza zRvars ver adgens, iyofa or nawilad. promotoris qmnian saerTo pirvelad transkripts wina nawilis nukleotidur Tan- kompleqsuri i-rnm-s saxiT. mimdevrobas uerTdeba Cap-cila anu cila-aqtivatori. am cila-aqti- genebs gaaCniaT Semdegi funqciebi: vatoris gareSe transkrifciis Lac Z Slis ß-galaqtozidazas Saqrebad; dasawyebad rnm-polimeraza ope- Lac Y genis produqts warmoadgens galaq- rons ver uerTdeba. amave dros tozidpermiaza, romelic awarmoebs ß- TviTon Cap-cila unda iyos aqtivi- galaqtozidazas gadatanas ujredSi; rebuli ujredSi arsebuli geni Lac A akodirebs cila transacetila- cikluri adenozinmonofosfatiT zas, romelsac acetiluri jgufi acetil- (camf). Tu ujredSi camf-is kon- CoA-dan gadaaqvs ß-galaqtozidazaze. centracia dabalia, Cap-cila gen-regulators igive buneba operons ver uerTdeba. Sesabami- aqvs, rogorc struqturul genebs, anu sad, camf aris sasignalo niv- warmoadgens izolirebul cistrons Tiereba, romelic operonis dnm-s molekulaSi. geni-regulatori moqmedebisaTvis aucilebelia. Sem- akontrolebs cila-represoris sinTezs, dgom modis nukleotidTa Tan- romelic operatoris struqturaze mimdevroba, romelsac ukavSirdeba gamorCeulad moqmedebs. pirdapiri cde- rnm-polimeraza da iwyebs mis biT damtkicebulia, rom E. Coli-s Lac - transkrifcias operonis sigrZis operoni Seicavs 10 molekula represors. gaswvriv. operatorSi ori non- TiToeuli molekula cnobs 300 nm sigrZis sens kodonis arsebobis gamo dnm-s 11-12 fuZeTa wyvils. erTi maTgani transkrifcia wydeba da i-rnm-s specifikurad aris dakavSirebuli gen- gadaweris ganaxleba xorcieldeba operatorTan da saWiroebisamebr aCerebs mxolod genTa operatoris bolo mis moqmedebas. nukleotididan; rodesac baqteriebis sakveb are- 2. promotoridan 21 nukleotiduri Si xvdeba laqtozis (rZis Saqari) wyvilis Semdeg moTavsebulia geni- molekulebi, laqtozidan sasignalo operatori, romelTanac kavSir- niSani gadadis cila-represorTan. am deba geni-regulatoris mier sin- SemTxvevaSi adgili aqvs alosterul Tezirebuli transkrifciis efeqts. – dabalmolekuluri SenaerTebi SemaCerebeli faqtori _ cila- (laqtoza), ukavSirdeba ra cilas, represori; cvlis mis biologiur aqtiurobas, 3. geni r+, romelic ganapirobebs kavSirs inaqtivirebuli cila-represori ver momaval i-rnm-sa da ribosomebs ukavSirdeba gen-operators. amis ga- Soris; mo gen-operatori gadadis aqtiur genis moqmedebis molekuluri meqanizmebi 101 suraTi 4.5 cila aqtivatori rnm-polimeraza cila terminatori Z Y A genebi regulatori promo- opera- tori tori struqturuli  - galaqtozidaza galaqtozidpermeaza rnm galaqtozidtransacetilaza cilebi represoris induqtorTan represori araaqtiuri kompleqsi produqti induqtori daSla E.coli-s laqtozis operonis muSaobis sqema (Griffiths et al., 1996) mdgomareobaSi, rac struqturul genTa derepresiis mizezi xdeba da yvela struqturuli genidan iqmneba 1985 wels genis gansazRvruli qimiu- i-rnm-s transkrifciis SesaZlebloba ri moqmedebis aRmoCenisaTvis f.Jakobs (sur. 4.5). yovelive amis Semdgom xdeba (F.Jacob), a.lvovsa (A.Lwoff) da J. monos 3 struqturuli genis mier kodirebuli (J.Mono) mieniWaT nobelis premia. 3 cilis sinTezi. radgan laqtozis mier inaqtivirebuli cila represori ar uerTdeba gen-operators, regulaciis am nukleotidTa TanmimdevrobebSi CarTu- saxes ewodeba negatiuri induqcia. lia e.w. `gaCumebuli~ ubnebi. arsebuli monacemebidan gamomdinare, unda aRiniSnos, rom evkariotebSi genTa moqmedebis detaluri makontrolebeli genTa organizaciis principi meqanizmebi bevrad gansxvavdebian evkariotebSi prokariotebisagan da ZiriTadad jer kidev ar aris Seswavlili. evkariotuli ujreduli dnm Sedis evkariotuli genis struqtura nukleoproteidul SemadgenlobaSi, ganixileba adamianis hemoglobinis ß - sadac 1/3 aris dnm, 1/3 histonebi da 1/3 jaWvis genis magaliTze. es geni Sedgeba qromosomuli mJave cilebi. evkariotul Semdegi elementebisagan (sur. 4.6): ujredebSi aris 3 saxis rnm polimer- aza (i-rnm, satrnm, r-rnm). evkariotuli 1. promotoris ubani, romelic pasu- xismgebelia rnm-polimerazas da- organizmebis bevri geni mozaikuri kavSirebasa da transkrifciis Semadgenlobisaa, sadac makodirebel 102 Tavi 4 adamianis genetika iniciaciaze. es ubani Seicavs 3 sxva- leotidis sigrZeze. Tu aaTaaa Ta- dasxva elements da ganlagebulia namimdevrobaSi SemTxveviT warmoiSva transkrifciis sainiciativo saitis raime mutacia, maSin poli (a) - `kudi~ win (95-26 n.w-iT); rnm-s ar emateba da transkrifcia ar Cerdeba. 3' transkribad bolo ubanSi 2. acaTTg Tanamimdevroba, romelzec ganlagebulia enxanseris Tanamimdevroba inicirdeba transkrifcia. mas (aaTaaa saitidan daaxloebiT 600-900 xSirad uwodeben kep-Tanamimdev- fuZeTa wyvili), romelic aucilebelia robas imitom, rom is axdens dnm-s momwifebuli eriTrocitebis _ globinis 5'’bolos kodirebas; genis droebiTi da sivrcobrivi eqspre- 3. aTg kodoni translaciis iniciatoria. siisaTvis (sur. 4.6). igi ganlagebulia transkrifciis promotori. evkariotTa genomSi, iniciaciis wertilidan 50 fuZeTa romelic transkribirebs i-rnm-s, wyvilis dacilebiT. transkrifciis aRmoCenilia ori tipis cis-regula- iniciaciis da translaciis werti- toruli dnm-s Tanamimdevroba _ pro- lebs Soris mdebare midamos, motori da enxanseri (gamaZlierebeli). romelic warmodgenilia 50 fuZeTa promotori Cveulebriv ganlagdeba wyviliT, ewodeba salidero Tanamim- uSualod transkrifciis sawyisi saitis devroba; win, sadac iwyeba transkrifcia, da 4. egzoni, romelic Seicavs 90 fuZe- misi sigrZe Seadgens daaxloebiT 100 Ta wyvils, axdens adamianis hemo- azotovan fuZeTa wyvils (sur. 4.6). globinis ß - jaWvis 1-30 aminomJavas promotoris ubani aucilebelia rnm kodirebas; polimeraza II-s transkrifciis zusti iniciaciisaTvis. genis promotorebs, 5. 140 fuZeTa wyvilisagan Semdgari romlebic asinTezireben i-rnm-s Se- introni, romelic ar Seicavs he- darebiT did raodenobas, msgavsi moglobinis makodirebel Tana- struqturebi aqvT. isini Seicaven TaTa mimdevrobebs; Tanamimdevrobebs (maT uwodeben TaTa 6. egzoni, romelic Seicavs 222 fuZeTa boqss), romelic ganlagdeba daaxloebiT wyvils, axdens 31-104 aminomJavaTa 30 fuZeTa wyvilis daSorebiT genis 5' kodirebas; mxaridan, sadac iwyeba transkrifcia. promotoris wina elementi warmoadgens 7. didi introni, romelic Seicavs caaT Tanamimdevrobis variacias. 850 fuZeTa wyvils. mas araviTari wvlili ar Seaqvs hemoglobinis enxanseri (transkrifciis gamaZlie- cilovan struqturaSi; rebeli) aaqtiurebs promotoris uti- lizacias, akontrolebs ra transkrifciis 8. egzoni, romelic Seicavs 12 fuZeTa siswrafesa da efeqturobas mocemuli wyvils, axdens 105-146 aminomJavaTa promotoridan. enxanserebis umciresoba kodirebas; SeiZleba lokalizdes intronebSi an 9. translaciis terminaciis kodoni genis 3' bolos win. enxanserebi aaq- Taa; tiureben mxolod cis-mdgomareobaSi myof promotorebs (e.i. imave qromosomaSi 10. 3' transkribadi ubnis bolo, mdebare promotorebs), magram maT SeuZ- romelic ar translirdeba cilaSi. lia funqcionirebis gagrZeleba did man- es ubani Seicavs aaTaaa Tanamimdev- Zilebzec. garda amisa, isini SesaZloa robebs, romelic aucilebelia trans- arsebobdnen ara marto 5'-boloze, aramed kribad rnm-s `kudTan~ daaxloebiT 200-300 dnm-s meore Zafzec. adeninis naSTis misaerTeblad. es poli (a) sailenseri (transkrifciis Sema- _ `kudi~ ukavSirdeba rnm-s daaxloebiT sustebeli). enxanserebsa da sailenserebs 20 fuZis mere aauaaa Tanamimdevrobebis Soris ar aris `Sromis~ mkveTri ganawileba, Semdgom. transkrifciis damTavrebamde radgan isini Cveulebriv urTierToben is grZeldeba daaxloebiT 1000 nuk- genis moqmedebis molekuluri meqanizmebi 103 suraTi 4.6 transkrifciis translaciis translaciis sainiciacio saiti sainiciacio saiti terminaciis saiti acaTTg (kep-saiti) aTg (50) Taa a promotori 30 31 104 105 146 egzoni 1 egzoni 2 introni 2 egzoni 3 promotoris lideri 5' - elementi introni 1 treileri TaTa boqsi poliadenilirebis saiti - aaTaaa transkrifciis terminaciis saiti b enxanseri enxanseri sekvenirebuli kep-saitis promotori translaciis sainiciacio saiti 5' egzoni 1 egzoni 2 egzoni 3 translaciis terminaluri saiti 3' a. evkariotuli organizmis genis struqturis organizacia (Lodish et al.,1995); b. promotoris sekvenirebeli suraTi (Gilbert, 2006) 104 Tavi 4 adamianis genetika suraTi 4.7 geni  es aris speiserebiT insulatori enxanseri SemosazRvruli nukleinmJavas promotori monakveTi, romelsac axasaTebs specifikuri nukleotiduri Tanamimdevroba; warmoad- gens funqciis erTeuls, gan- sxvavbuls funqciis sxva er- Teulisagan; ganicdis invari- antul avtoreproduqcias da eqvemdebareba mutaciur pro- transkriptosoma cess. (T. leJava) or insulators Soris arsebuli genis aqtivacia (Жимулев, 2006) soliteri genebi sakmaod bevr genTan. dnm-s erTma da imave Tanamimdevrobam SesaZlebelia miiRos mravalujrediani organizmebis haploi- enxanseris an sailenseris mniSvneloba dur genomSi cilis masinTezirebeli ujredis tipis gaTvaliswinebiT. es genebis 25-50% erTi calad aris Tanamimdevrobebi warmoadgenen dnm-s warmodgenili. aseT genebs soliteri mokle Tanamimdevrobebs (100-200b), genebi ewodeba. romelic regulatoruli cilebis mimag- kargad aris Seswavlili wiwilas rebis adgilia. regulatorul cilebTan lizocimis soliteri geni. lizocimi urTierTobisas icvleba genTa aqtiuroba aRmoCenilia adamianis cremlSi, ner- dnm-s calkeuli ubnis konformaciuli wyvSi, kvercxis cilaSi. lizocimi cvlilebis gamowvevis gamo. arRvevs baqteriuli ujredis kedlis insulatori _ dnm-s mokle Tana- polisaqaridul Sres. mimdevrobebi (300-1000b), romelic lizocimis transkrifciis erTeuls ganapirobebs genis SefardebiT warmoadgens erTi geni, romelsac gaaCnia damoukideblobas, axdens ra promotorsa 15 kb dnm-s nukleotiduri Tanamimdevroba, da enxansers Soris urTierTqmedebis Seicavs oTx egzonsa da sam introns. Seferxebas. insulatorebi aRmoCenilia flankirebuli ubnebi rogorc marjvniv, adamianis globinis genebis sistemaSi, ise marcxniv, warmodgenilia daaxloebiT retrotranspozon gypsy-Si da drozo- 20 kb aratranskribadi nukleotiduri filas BX-C genTa blokSi. yvelaze kargad TanmimdevrobiT (sur. 4.8). aris daxasiaTebuli insulatoruli elementebi scs da scs’ da 340b fragmentebi retrotranspozon gypsy-Si. varaudoben, dispersuli genebis ojaxebi rom scs Tanamimdevrobebi esazRvrebian arsebobs 5-10 kb sididis msgavsi, magram genebs orive boloSi. mxolod or araidenturi genebis aslebi _ genebis insulators Soris midamoSi enxanserul ojaxebi. isini iqmnebian acentruli Tanamimdevrobebs cila aqtivatorTan genebis dublikaciis Sedegad. aseTi kavSirisas SeuZliaT maryuJebis war- genebis ojaxebi xerxemlianebSi Sead- moqmna da urTierTkavSiris damyareba genen cilamasinTezebeli dnm-s naxevars. promotorTan (sur. 4.7). genebis ojaxebi SeiZleba moicavdnen genis moqmedebis molekuluri meqanizmebi 105 suraTi 4.8 50-60 kb i - rnm lizocimi i - rnm wiwilis lizocimis masinTezirebeli geni-soliteri warmodgenilia oTxi egzoniT (Savi ujra) da sami introniT (TeTri ujra) (Baldas et al., 1981) mcireoden an Zalian bevr gens. magaliTad, zebia is, rom zogierT maTganSi Car- aqtinebi - 5-dan 30-mde. keratinebi - 20- Tulia terminaciis kodonebi, zogSi ze mets, miozinis mZime jaWvi - 5-dan 10- aRiniSneba CarCos gadaadgileba, zogSi mde. tubulinebi - 3-dan 15-mde, globine- ki darRveulia promotoris funqcia. bi - 5-mde, histonebi - 100-dan 1000-mde. genebis ojaxebis mier sinTezirebuli cilebi erTdebian cilaTa ojaxebad. genis ojaxis tandemuri wyoba genebis ojaxis magaliTs warmoad- rig SemTxvevaSi ujredebi saWiroeben gens adamianis β-globinis genebis zogierTi genebis produqtebis did klasteri, lokalizebuli me-11 qromo- raodenobas. aseTi genebi qmnian tan- somaSi. β-globinis genebis ojaxi Seicavs demur wyobebs. amis magaliTia birTvakis 5 funqciur gens (sur. 4.9). am genTa maorganizebeli ubnebi, romlebic war- mier sinTezirebuli cilebi erTmaneTs moadgenen ribosomuli rnm-s mako- emsgavseba. ori identuri β-globinis direbeli genebis tandemur wyobas. polipeptidi uerTdeba or identur dadgenil iqna, rom drozofilas X- -globins (romelic genebis sxva ojaxidan qromosoma Seicavs rnm-s masinTezirebel sinTezirdeba). es oTxi polipeptidi da 200-mde gens. genTa aseTi siWarbe patara hemis jgufebi qmnian hepoglobinis aris erTaderTi gza ujredebis didi molekulas. varaudoben, rom genebis raodenobiT r-rnm-s uzrunvelsayofad. ojaxebi, warmodgenilni acentrul genTa radiaqtiuri ribosomuli rnm-s dublikaciiT, warmoiSvnen araTanabari lRobis maCveneblis saSualebiT dadginda krosingoveris Sedegad (sur. 4.9). wrfivi damokidebuleba birTvakis maor- ganizebeli dnm-s raodenobasa da 18s, 28s r-rnm-s Soris. aseve it situ hibridizaciam fsevdogenebi daadastura birTvakis maorganizebeli genebis ojaxSi gaerTianebuli zogierTi raionis dnm-s zomebis proporciuloba geni xdeba arafunqcionirebadi, aratrans 18s da 28s r-rnm-s zomebTan. dadgenil iqna, -kribadi. aseT genebs fsevdogenebs rom drozofilas Y qromosoma Seicavs uwodeben. adamianis β globinis genebis daaxloebiT genebis 150 tandemur asls. klasteri Seicavs or fsevdogens adamianis birTvakis maorganizebel akro- (sur. 4.9). fsevdogenebis dnm-s nukleo- centrul qromosomebSi r-rnm-s genebi tidTa sekvenirebisas aRmoCnda, rom warmodgenilia tandemurad ganlagebuli fsevdogenebi inaxaven β-globinis 250 asliT. 5s-rnm-s genebi _ 2000 asliT. genebis msgavs egzon-intronul struq- genebis wyobaSi TiToeuli asli aris turas. fsevdogenebi warmoiqmnen rigi zustad, an daaxloebiT zustad, sxva acentruli genebis dublikaciis gziT. wevrebis msgavsi. fsevdogenebis arafunqcionirebis mize- 106 Tavi 4 adamianis genetika suraTi 4.9 a  G 50 90 130 \ 850 126 132 Alu saiti aratranslirebadi egzoni introni raioni Alu -globinis geni mSobelTa qromosomebi b rekombinacia (araTanabari krosingoveri) rekombinaciuri qromosoma a – adamianis  -globinis genis klasteri, lokalizebuli me-11 qromosomaze. 1 da 2 - fsevdogenebia; b –  globinis genis dublikacia araTanabari krosingoveris Sedegad (Lodish et al., 1995) tandemuri wyobis magaliTs war- dupleqsur struqturebs _ polindro- moadgens satransporto rnm-s genebic. mebs (sur. 4.11). rig SemTxvevebSi inver- adamianis genomSi aris daaxloebiT 50 tirebul ubnebs Soris erTvebian gan- saiti, romelic Seesabameba sat-rnm-s sxvavebuli tipis ganmeorebadobani. ada- sxvadasxva tips da TiToeul saitSi mianis qromosomebSi polindromuli dnm lokalizebulia 10-dan 100 aslamde. SemTxveviTad aris ganawilebuli. histonuri genebisaTvis, iseve rogorc r-rnm-s genebisaTvis, damaxasiaTebelia amplifikacia tandemuri wyoba (sur. 4.10). zogierTi geni replikaciis dros gamodis sat-rnm-s tandemurad ganmeorebadi qromosomaTa Semadgenlobidan da iwyebs nukleotiduri Tanamimdevrobebis sekve- avtonomiur replikacias, ris Sedegadac nirebam aCvena, rom mravalricxovani warmoiSoba asobiT da milionobiTac genuri aslebi identurni arian. mosa- misi msgavsi aslebi. am movlenas ampli- lodnelia, rom mutacias nakleb fikacia ewodeba. es damaxasia-Tebelia im mniSvnelovani funqciis mqone saitebSi ujredebisaTvis, romlebic moiTxoven SeuZlia gamoiwvios garkveuli cvli- didi raodenobiT r-rnm-s da cilis lebebi. rogorc Cans, ujredSi molekulis sinTezs. amis magaliTi arsebobs garkveuli meqanizmi, romelic SeimCneva adamianis oocitebSic. uzrunvelyofs tandemurad gawyobil wevrTa stabilurobis SenarCunebas. polindromebi magnifikacia dnm-s spiralis renaturaciis SemTxve- ribosomuli rnm-s genebis raodenobis vaSi invertirebuli, saSualo sixSiris gazrdis saSualebad iTvleba e.w. mag- ganmeorebad TanamimdevrobaTa dnm-s nifikacia. magnifikacia xorcieldeba erTZafiani ubnebi (ABC, CBA) warmoqmnian amogdebuli rgolovani r-dnm-s genebis genis moqmedebis molekuluri meqanizmebi 107 suraTi 4.10 H1 H2A H2B H3 H4 H1 H2A H2B H3 H4 H1 H2A H2B H3 H4 histonuri genebis tandemuri wyoba (Baldas et al., 1981) replikaciiT da Semdeg qromosomaSi Zod, naCveneb iqna, rom imunoglobuli- CarTviT. Sesabamisad izrdeba r-rnm-s nis mZime γ-jaWvis struqtura Sedgeba masinTezirebel genTa odenoba. igi xuTi domenisagan da TiToeul maTgans inaxeba rig TaobebSi. magnifikaciis aqvs specifikuri funqcia. CH3 domeni induqtorad iTvleba r-rnm-s genebis monawileobs ujredTa zedapirTan ur- dakargva araTanabari krosingoveris TierTobaSi. CH2 domeni uerTdeba kom- Sedegad an Sesabamisi qromosomuli plementis molekulas. H-saxsriani nawilis delecia. garda r-rnm-s genebisa, domeni SesaZleblobas iZleva antigen- histonuri genebis magnifikaciac xdeba. kavSiris mqone saitebi moixaron. CH1 domeni uerTdeba msubuq jaWvs, xolo variabeluri ubnis domeni _ VDJ qmnis moduluri genebi antigendakavSirebul saits. TiToeuli genomis struqturul-funqciur organi- am domenis kodireba xdeba calkeuli zaciaSi dnm-s nukleosomuri Zafi egzonebiT (sur. 4.12). warmoqmnis funqciur specifikur ubnebs dabali simkvrivis mqone lipo- _ domenebs, romlebic warmoadgenen proteinis receptori gaxda pirveli maryuJisebur struqturas (Cveulebriv magaliTi egzonebis gadaadgilebisa, rac 20000-80000b), dakavSirebuls koferment- imas niSnavs, rom egzonebs SeuZliaT erT Tan, regulatorul molekulebTan, bir- genSi ganaxorcielon dublikacia da Tvul matriqsTan da ujredis membra- Semdgom gadavidnen meore genSi. genebi, nebTan. TiToeuli funqciuri centri romlebic akodireben cilebsa da rnm-s Cveulebriv warmoadgens naxevrad av- molekulas, iyofa 3 kategoriad: tonomiur sistemas, romelSic spe- cifikurad Cawyobilia polipeptiduri 1. struqturuli genebi, romlebic ako- jaWvi. domeni dasaSvebia warmoadgendes direben cilebs. Suamavlad war- funqciur erTeuls _ gens. modgenilia i-rnm; 2. genebi, romlebic akodireben ri- domenis funqcionirebaSi insulato- bosomul da satransporto rnm-s. rebs akuTvneben gansakuTrebul mniSvne- genTa produqtebad am SemTxvevaSi lobas. gamodian TviT ribonukleinis mJavebi, 1978 wels u. gilbertma (Gilbert, 1978) romlebic transkribirdebian gene- gamoTqva hipoTeza intronebis arsebobis bisagan (konstituciuri genebi); asaxsnelad, romlis mixedviTac evka- 3. regulatoruli anu aqceptoruli riotuli genomi Sedgeba moduluri genebi, romlebic akodireben cilebsa erTeulebisagan, rac misi `Serevisa da da patara rnm-s molekulebs genTa gadanawilebis~ SesaZleblobas gvaZ- transkrifciisa da qromosomaTa levs. egzonebi akodireben cilis replikaciis procesebis reguli- funqciur domenebs da maT SeuZliaT rebisaTvis. termini `aqceptoruli evoluciis procesSi damoukideblad ga- genebi~ gamoiyeneba imis gamo, rom daxalisdnen. rig gen-regulatorTa moqmedeba da- 1979 wels gamoCnda pirveli mona- mokidebulia cila-regulatorTan cemebi am hipoTezis sasargeblod, ker- specifikur kavSirze. 108 Tavi 4 adamianis genetika suraTi 4.11 ccTagTTa gTacg TaacTagg 1 2 T a a c T a g g c c T a g T T a a c c g g T g a c c a g g T polindromebi - dnm-s erTZafiani dupleqsuri struqturebi. 1.2-aRniSnulia polindromuli nukleotiduri Tanamimdevrobebi (dubinini, 1985) evkariotebSi sami sxvadasxva rnm- transkrifcia polimeraza transkribirebs rnm-s sami sxvadasxva tipis genebisagan. Rnm-polim- 1958 wels f.krikma (Crick, 1958) wamoa- eraza-I asinTezirebs 18, 28 da 5,8 S rnm-s; yena debuleba molekuluri biolo- rnm-polimeraza II asinTezirebs i-rnm-s im giis centra luri dogmis Sesaxeb, genebis matricaze, romlebic akodireben rac imaSi mdgomareobs, rom dnm-dan cilebsa da zogierTi mcire zomis rnm-s; informacia gadadis i-rnm-ze da iqi- rnm-polimeraza III axorcielebs 5S r-rnm-s, dan ribosomebSi polipeptidis sin- sat-rnm-s da darCenili mcire zomis rnm-s Tezis gansaxorcieleblad. rnm-s Sem- genebis transkrifcias. cvel virusebSi ukutranskrifciis gziT TiToeul gens gaaCnia regulator- (aRmoaCines 1970 wels  Temin and Mi- uli nawili, sadac iwyeba makodirebuli zutani, 1970) informaciis rnm-dan dnm- ubnis transkrifcia, sadac aris Ca- ze gadatanis faqtis miuxedavad, genTa werili informacia cilis struqturis eqspresiis ZiriTad gzad mainc (tran- Sesaxeb da terminaluri nawili, sadac skrifcia, translacia) dnm-rnm-cila rCeba. Tavdeba transkrifcia. D dnm-s ormagi dnm-dan i-rnm-ze genetikuri in- spirali promotoris ubanSi ganicdis formaciis gadatanis process ewodeba denaturacias prokariotebSi rnm-polim- transkrifcia. i-rnm-s sinTezi, romelsac erazis, xolo evkariotebSi transkrif- akodirebs mocemuli geni, aris genis ciis kompleqsis moqmedebisas, romlis eqspresia. Sedegad warmoiSoba e.w. transkrifciuli prokariotebSi erTaderTi rnm-poli- buSti” (sur. 4.13). rnm sinTezirdeba 5'- meraza warmoadgens cilovan kompleqss, dan _ 3'-s mimarTulebiT dnm-s erT-erT romelic Sedgeba _ sakuTriv rnm-polim- Zafze, romelic iwodeba samatrico Za- erazisa da σ-faqtorisagan. asinTezirebs fad, xolo meore _ makodirebel Zafad. yvela saxis rnm-s: i-rnm-s, sat-rnm-s da transkrifcia mTavrdeba, rodesac rnm- r-rnm-s. polimeraza aRwevs terminalur ubans anu terminators. genis moqmedebis molekuluri meqanizmebi 109 suraTi 4.12 IgG IgG IgG IgG VD1 egzoni 1 egzoni H egzoni 2 egzoni 3 saxsari CH1- CH2- domeni domeni cvladi ubani CH3-domeni IgG cilis mZime jaWvSi egzonebsa da domenebs Soris Sefardeba. TiToeuli domeni kodirebulia calkeuli egzonis mier (Sakano, 1979) prokariotebSi transkrifciis pro- cesi mimdinareobs holoferment rnm-po- limeraziT, romelic Seicavs sakuTriv 1993 wels danawevrebuli genebis aRmo- rnm-polimerazasa da masTan dakavSirebul CenisaTvis f.Sarps (P.Sharp) da r. ri- σ-faqtors. rnm-polimeraza 4 polipep- xards (R.Richard) mieniWaT nobelis pre- tidisagan Sedgeba:ori а da aseve β mia. da β'erTeulisagan. rnm-polimeraza axorcielebs ZiriTad reaqcias -–ribonuk- 4. -10 da -35 nukleotidTa Tanamimdev- leotidebis polimerizacias. misi funqcia robebis daSoriSoreba. mdgomareobs dnm-s ormagi spiralis erT- pirvelad rnm-polimeraza ukavSir- erTi Zafidan rnm-s kopirebaSi. σ-faqtori deba -55 dan +20-mde arsebul nukleotidur aucilebelia genis sawyis nawilSi pro- motoris mosaZebnad. Tanamimdevrobebs (sur. 4.14). sainiciacio kompleqsi Seicavs rnm-polime razasa da promotors gaaCnia rnm-polimerazis σ-faqtors, romelic sustad ukavSirdeba mier amosacnobi gansazRvrul nukleo- ra -35 nukleotidur Tanamimdevrobis tidTa Tanamimdevrobebi. monakveTs, akontrolebs promotorze prokariotTa transkrifciis sawar- rnm-polimerazas zust moTavsebas. amis moeblad aucilebelia oTxi piroba: Semdgom rnm-polimeraza ukavSirdeba - 10 nukleotidur Tanamimdevrobis axlos 1. transkrifciis sastarto wertilis mdebare pribnovis raions. imavdroulad arseboba; ixsneba 17 nukleotiduri (a-T) Tana- 2. -10 mdgomareobidan gansakuTrebul mimdevrobis sigrZis dnm-s ormagi spira- nukleotidTa Tanamimdevrobebis li. arseboba; radgan promotorebi ganirCevian 3. -35 raionSi gansakuTrebul nukleo- erTimeorisagan nukleotiduri Tana- tidTa Tanamimdevrobebis arseboba; mimdevrobebiT, rnm-polimerazis dakav- Sirebis efeqturoba da, Sesabamisad, 110 Tavi 4 adamianis genetika suraTi 4.13 moZraobis mimarTuleba dnm-s makodirebeli Zafi denaturaciis wertili renaturaciis wertili dnm samatrico jaWvi rnm damakavSirebeli saiti rnm-s hibridi transkrifciuli `buSti~ transkrifciis msvlelobisas rnm-polimeraza dnm-s ormagi spiralis denaturirebas axorcielebs da Semdgom kvlav aRadgens (Lewin, 2000) transkrifciis siCqare sxvadasxva genSi genis erT-erTi yvelaze cnobili sakmaod gansxvavebulia. regulatoruli elementi aris pro- motori, romelic Sedgeba ramdenime σ-faqtoris disocirebisas rnm- elementisagan. maT Soris transkrifciis polimeraza -30 mdgomareobis zeviT dasawyisis wertilTan yvelaze axlos mokldeba ramdenime nukleotidiT, fer- aris TaTa _ domeni (5'-TaTaaa-3'), mas aseve mentis gadanacvlebisas ufro kompaqturi uwodeben hognesis domens, an golberg- xdeba da gardaiqmneba elongaciis kom- hognesis domens. amis Semdgom ganewyobian pleqsad (sur. 4.14). domenebi caaT (5'-ggccaaTcT-3') da gc evkariotebSi transkrifciis procesi (5'-ggccgg-3'). caaT domeni arsebiT rols gacilebiT rTulad mimdinareobs sami TamaSobs transkrifciis iniciaciaSi. garemoebis gamo: mecnierTa azriT TaTa da gc Tanamimdev- robebs gaaCniaT mxolod damxmare roli. 1. transkrifcia xorcieldeba sami rac Seexeba i-rnm-s transkrifciis sas- sxvadasxva saxis rnm-polimerazis tarto wertils, es raioni gamoixateba monawileobiT; formuliT _ Py2 CAP5. 2. evkariotebSi rnm-polimerazas ar yvela tipis promotorebis trans- SeuZlia damoukideblad trans- krifciis iniciaciisaTvis aucilebelia krifciis inicireba. misi aqtiva- transkrifciis zogadi faqtorebis mona- ciisaTvis aucilebelia cilebis wileoba. isini ukavSirdebian rnm- didi raodenoba, romlebsac polimeraza II da sastarto wertilis ewodebaT transkrifciis zog- irgvliv qmnian kompleqss. sadReisod adi faqtorebi da romlebic gamoyofilia transkrifciis Svidi transkrifciis dawyebamde zogadi faqtori: TFIIA, TFIIB, TFIID, erTiandebian kompleqsebad. trans- TFIIE, TFIIF, TFIIH, TFIIJ. zogierTi maTgani krifciuli kompleqsis Camoyali- Sedgeba bevri polipeptidisagan. rTuli bebaSi monawileobas iReben regu- organizacia gaaCnia kompleqs TFIIH. latoruli cilebi. ZuZumwovrebSi rnmpolimeraza II moicavs 12- 14 polipeptids. transkribad kompleqsSi 3. evkariotTa regulatoruli cile- Sedian axlad aRmoCenili cilebi, bis umetesoba gavlenas axdens romlebsac uwodeben SRB-s (suppressor transkrifciis siCqareze. of RNA Pol II). isini uerTdebian rnm-po- genis moqmedebis molekuluri meqanizmebi 111 suraTi 4.14 iniciaciis kompleqsi, -50 -40 -30 -20 -10 1 +10 +20 Seicavs  faqtors da ukavSirdeba -35 - +20 n.w. elongaciis pirveladi kompleqsi, -50 -40 -30 -20 -10 1 +10 +20 35-dan - 55-mde raionSi  faqtori kargavs kontaqts dnm-Tan elongaciis saerTo kompleqsi -50 -40 -30 -20 -10 1 +10 +20 ukavSirdeba sigrZiT 30-40 n.w. dnm-s ubans transkrifciis mimdinareoba (Lewin, 2000) limerazis did suberTeuls. aRniSnu- aqtivaciisaTvis transkrifciis zogadi li cilebi exmarebian rnm-polimerazas, faqtorebis monawileobas. bevri ram daSalon nukleosomebi da moaxdinon dnm-s maTTan mimarTebaSi rCeba ucnobi. molekulis dekompaqtizacia. amis garda, evkariotul ujredebSi genetikur transkrifciis faqtori TFIIH urTier- regulacias axasiaTebs arsebiTi Tavi- Tobs cilebTan, romlebic monawileobas sebureba. es aris is, rom transkrifciis iReben dnm-s reparaciaSi. transkrifciis procesi damokidebulia qromatinis md- dawyebisaTvis rnm-polimeraza II unda gomareobaze. genTa represiis ZiriTad ganTavisufldes transkrifciis faq- meqanizms warmoadgens dnm-s kompaqtizacia torTa kompleqsisagan (TFIID, TFIIB, TFIIF, nukleosomur klasterebad. Tu dnm TFIIE da TFIIJ). TFIIH faqtoris erT-erT aris daxveuli mkvriv struqturad, suberTeuls gaaCnia proteinkinazuri aq- transregulatorul faqtorebs ar tiuroba da igi rnm-polimeraza II-s fos- gaaCniaT SesaZlebloba awarmoon trans- forilirebas axdens. fosforilirebis krifciis iniciacia. rodesac dnm, ro- Sedegad polimerazis molekula kon- melic Seicavs promotors, Sedis nukle- formacias icvlis da Tavisufldeba osomis SemadgenlobaSi, Sesabamisi transkrifciis yvela faqtorisagan, genebi ver transkribireben. Tu aRniSnul garda TFIID. Sedegad, ganTavisuflebuli genebs nukleosomebis formirebamde an rnm-polimeraza II iwyebs transkrifcias. formirebis dros daemateba cila, da- rnm-polimeraza II-s garda monawileobs kavSirebuli TaTa boqsTan (TFIID), maSin 50 ciliT warmodgenili transkrifciis qromatini xdeba transkrifciulad aqti- zogadi faqtorebi. xSir SemTxvevebSi es uri. birTvuli cilebis kavSiri genebTan kompleqsebi iwodeba transkriptosomebad. SesaZlebelia Sefasdes qromatinis dnm- ZuZumwovrebSi rnm-polimeraza I aza I-iT damuSavebisas. damuSavebuli da rnm-polimeraza III aseve saWiroeben qromatinisagan eqstragireben dnm-s da 112 Tavi 4 adamianis genetika suraTi 4.15 egzoni 1 egzoni 2 egzoni 3 introni 1 introni 2 dnm rnm-s sinTezi pro-i-rnm splaisingi i-rnm cilis sinTezi cila genSi gayofili individualuri makodirebeli raionebi dnm-dan cilaSi informaciis gadatanis procesi, kodirebuli genSi gayofili raionebiT (Lewin, 1994) ureven konkretuli genis radiaqtiul erTad, romlebic akodireben cilebs, k-dnm-Tan. Tu k-dnm poulobs Sesabamis sat-rnm-s, r-rnm-s, aris ubnebi, romlebic nukleotidur Tanamimdevrobas, es niS- ar akodireben araviTar produqtebs, navs, rom aRniSnuli geni ar iyo daculi ar Seicaven genetikur informacias. im qromatinis cilebiT dnm-aziT damuSavebisas ubnebs, romlebic moTavsebulia genSi da misTvis iyo misawvdomi. magram, Tuki makodirebel ubnebTan monacvleobiT, k-dnm-s zondi ver poulobs Sesabamis ewodeba intronebi, xolo genebis Tanamimdevrobebs, es niSnavs, rom geni makodirebul ubnebs _ egzonebi (gan- iyo daqvemdebarebuli dnm-azis moqmedebas sxvavebuli Semadgeneli nawilebis mqone da, rogorc Cans, misawvdomi iyo rnm-po- genebi 1977 wels aRmoaCines robertsma limerazisa da transregulatoruli faq- da Sarpma adenovirus-2-Si (Roberts and torebisaTvis. Sharp, 1977). aseTi saxis struqturuli organizacia aRmoaCndaT evkariotTa genebis umravlesobas, evkariotTa dnm-sa da rnm-s Semcvel vi rusebs. baqteriebsa genis struqturuli nawili da baqteriis virusebs – fagebs intronebi ar gaaCniaT. i-rnm-s sinTezis procesebis Seswavlisas zogierTi geni Seicavs erT an or aRmoCnda, rom transkrifciis produq- introns, magram xSirad maTi odenoba tebi birTvSi gacilebi metia, vidre metia. intronis zoma icvleba _ citoplazmaSi gadasuli rnm, romelic ramdenime aTeulidan ramdenime aTaseul monawileobs translaciaSi da Sedis nukleotidur wyvilamde. intronebs ribosomebSi. aseT rnm-s uwodes hetero- yovelTvis gaaCniaT 5' boloSi wyvili genuli birTvuli rnm an pro-i-rnm. pro- gT Tanamimdevroba, xolo 3'-boloSi i-rnm-s Seswavlisas gamoirkva, rom misi ag. intronTa saerTo sigrZe xSirad posttranskrifciuli gardaqmnebisas aRemateba egzonTa saerTo sigrZes. (procesingi) warmoiqmneba i-rnm (sur. 4.15). ”adamianis genomis”proeqtis monacemebiT aRmoCnda, rom genebSi im ubnebTan genomis dnm-s mxolod 1% Seadgens eg- genis moqmedebis molekuluri meqanizmebi 113 suraTi 4.16 promotorebi egzoni 1 egzoni 2 egzoni 3 egzoni 4 egzoni 5 terminatori 1 2 3 1 2 3 alternatiuli promotoris gamoyeneba egzoni 1 2 3 4 5 promotorebi 2 3 alternatiuli terminatorebis gamoyeneba 1 2 3 4 5 1 2 terminatorebi alternatiuli splaisingi 1 2 3 5 1 4 5 2 terminatorebi 2 terminatorebi alternatiuli splaisingis SesaZlebeli variantebi (Lewin, 1995) zonebs da 24% - intronebs (Venter et al., 2001). adamianis genomis”gamokvlevaTa alternatiuli splaisingi monacemebiT egzonTa saSualo raodenoba erT genze aris 7,8 (Venter et al., 2001). zogierT SemTxvevaSi egzonebi ar safuarebSi 95% genebisa Seicavs mxolod akodireben maTTvis damaxasiaTebel erT egzons. egzonebi transkribireben aminomJavur Tanamimdevrobebs. Sedegad, intronebTan erTad ise, rom pro-i- erTi genisagan translirdeba erTze meti rnm Seicavs rogorc egzonebis, ise i-rnm. Seusabamobas genTa raodenobasa intronebis transkribirebul ubnebs. da organizmis sirTules Soris, procesingis Semdgomi msvlelobisas, rodesac erT gens SeuZlia mogvces bevri romelic mimdinareobs birTvSi, pro- sxvadasxva transkripti, xsnis alterna- i-rnm-Si intronuli ubnebi amoiWreba, tiuli splaisingis arseboba (sur. 4.16). egzonebi erTdebian urTierTTan da (Graveley, 2001). aRwerilia erTi gen- momwifebuli i-rnm Seicavs mxolod idan mravali tipis rnm molekulis makodirebel egzonebs. egzonebis Seer- warmoSobis meqanizmebi transkrifciis Teba xorcieldeba ujredisaTvis da- iniciaciisa da terminaciis, aseve maxasiaTebeli TanamimdevrobiT. momwife- splaisingis cvalebadobis Sedegad. buli i-rnm-s formirebisas egzonebisagan alternatiuli promotorebis gamoyenebam transkribirebuli ubnebis SeerTebas dasaSvebia Secvalos transkriptis 5'- ewodeba splaisingi (sur. 4.16). bolo, alternatiuli terminatorebis gamoyenebisas SesaZlebelia Seicvalos transkriptis 3'-bolo. aseTi cvli- 114 Tavi 4 adamianis genetika li rnm-sagan - 60%. is warmoadgens suraTi 4.17 ujredis cilis qarxanas. ujredSi rnm cilis molekulaTa odenoba aRwevs 10 milionamde (Курчанов, 2006). yvela ribosoma Sedgeba ori _ didi da patara suberTeulisagan. ribosomaTa da maTi suberTeulebis sidide izomeba xsnarSi sedimentaciis siCqariT (S - svedbergis konstanta). prokariotebis ribosomebi xasiaTdebian 70S (30S + 50S), evkariotTa _ 80S (40S + 60S). mitoqondriebis ribosomebi emsgavsebian prokariotTa ribosomebs. ribosomebi Seicaven or ubans _ A (aminoaciluri) da P _ (peptiduri), romlebic ZiriTad katalizur centrebs warmoadgenen. maT garda aris fermentebis damakavSirebeli sxva centrebic. splaisoma orive suberTeulis Sesabamisoba ganapirobebs ubnebis specifikurobas. splaisomis eleqtromikroskopuli suberTeulebis disociaciis SemTxveva- ikrofotografia (Lodish et al., 1995) Si maTi specifika ikargeba. ribosomas gaaCnia oTxi saxis r-rnm. sami maTgani warmoiqmneba erTiani winamorbedisagan lebebi SesaZlebelia moxdes i-rnm-s (45S-rnm), romlis sinTezi xorcieldeba sainiciacio da terminatorul nukleo- birTvakSi rnm-polimeraza I-s saSua- tidur TanamimdevrobebSi (sur. 4.17). lebiT. birTvakSi koncentrirdeba qro- dasaSvebia alternatiuli splaisingis mosomaTa maryuJebi, romlebic Seicaven meore gzac, rodesac icvleba egzonebis r-rnm-s genebs. am genebs gaaCniaT mra- gaerTianebis Tanamimdevroba da erTi vali asli. adamianis xuT wyvil geni funqcionirebs, faqtobrivad, birTvakmaorganizebeli qromosomebis rogorc ramdenime. boloebSi e.w. `Tanamgzavris Zafebze~ splaisingi mimdinareobs gansakuT- lokalizebulia r-rnm-s genebis 200- rebul struqturebSi _ splaisomebSi, mde asli. meoTxe r-rnm (5S-rnm)-s sin- (sur. 4.18) romelic Sedgeba pro i-rnm Tezi mimdinareobs rnm-polimeraza III sa da mcire zomis ribonukleoproteiduli monawileobiT birTvakis gareT - I-li (snRNP) warmonaqmnebisagan (sur. 4.18). qromosomis distalur nawilSi. ribosoma translacia i-rnm-s molekula (evkariotebSi pro- es aris procesi, rodesac genetikuri in- cesingis Semdgom da prokariotebSi formacia birTvidan gadaitaneba cito- procesingis gareSe) monawileobs sxva plazmaSi ribosomebSi polipeptidis war matricul procesSic - translaciaSi mosaqmnelad. sat-rnm-s molekulebi war- (cilis sinTezSi), romelic mimdinareobs moadgenen adaptorebs. sat-rnm-s mo- ribosomebSi. am TvalTaxedviT mizan- lekulebi ganewyobian erTimeoris gver- Sewonili iqneba, rom ganvixiloT ri- diT i-rnm-s kodonebis wyobis Sesabamisad, bosoma. romlebTanac xdeba antikodonebis SeerTeba (azotovan fuZeTa SeerTebis ribosoma (sur. 4.19) warmoadgens safuZvelze). amis Semdeg sat-rnm-Tan ujredis organoids, romelic Sedgeba dakavSirebuli aminomJavebi erTdebian cilisa (daaxloebiT 40%) da ribosomu- genis moqmedebis molekuluri meqanizmebi 115 suraTi 4.18 egzoni introni egzoni 2 introni 2 egzoni 1 patara oni egz birTvuli rnm patara birTvuli rnm-s monawileoba splaisingis mimdinareobaSi (Griffiths et al., 1996) peptiduri bmebiT. trans laciis procesSi gamoiyofa Semdegi stadiebi (sur. 4.20). 1993 wels danawevrebuli genebis aRmo- 1. aminomJavebis aqtivaciis pro- CenisaTvis f.Sarps (P.Sharp) da r. rix- cesi. Tavisufali aminomJavebis ards (R.Richard) mieniWaT nobelis pre- aqtivacia xorcieldeba garkveuli mia. fermentebis monawileobiT (aminoa- cil-satrnm-sinTetaza) atf-is Tanao- bisas. TiToeuli aminomJavasaTvis xorcieldeba ise, rom sastarto arsebobs Tavisi fermenti da kodoni aug `aradasrulebul~ Tavisi sat-rnm. aqtiuri aminomJava P-ubanSi xvdeba. kompleqsi aa- uerTdeba Tavis sat-rnm-s da sat-rnm satrnm antikodon (uac)- warmoqmnis kompleqss aminoacil- is sa SualebiT uerTdeba i-rnm-s sat-rnm (aasat-rnm). mxolod aqtiur sas tarto kodon aug-s. arsebobs aminomJavas gaaCnia SesaZlebloba, mraval ricxovani cilebi _ ini- warmoqmnas peptiduri kavSirebi da ciaciis faqtorebi (ZiriTadad Seqmnas polipeptiduri Zafi. evkariotebSi). 2. iniciacia.cilis sinTezis inicia- imisaTvis, rom antikodonma amo- ciisaTvis aucilebelia proka- icnos i-rnm, saWiroa gaxsnili riotebSi formilmeTioninis sat-rnm, iyos e.w. sainiciacio kodoni - aug. xolo evkariotebSi - meTioninis sxvadasxva tipis informaciuli rnm-s sat-rnm. rogorc wesi, aminomJaviani Seswavlisas aRmoCnda, rom TiToeul sat-rnm ukavSirdeba ribosomis A maTgans 5' boloSi aqvs ag mdidari ubans da Semdeg gadadis P ubanSi. Tanamimdevrobani, xolo r-rnm-s bo- iniciacia iwyeba i-rnm-s 5-bolos loSi cu mdidari Tanamimdevroba, SeerTebiT disocirebuli ribosomis romelic i-rnm nukleotiduri patara suberTeulTan. SeerTeba Tanamimdevrobis komplementarulia 116 Tavi 4 adamianis genetika suraTi 4.19 P - saiti A - saiti patara suberTeuli antikodoni P - saiti A - saiti T a c sainiciacio sat-rnm formil- a meTionini u g didi suberTeuli g a a c a u g u u c g g u c c ribosomis P da A saitebi (Klug and Cummings, 1994) da warmoqmnis i-rnm-Tan stabilur 3. elongacia. axali sat-rnm (am Sem- kompleqss. iniciaciis dros (pro- TxvevaSi alaninis) ukavSirdeba kariotTa magaliTze) ribosomis i-rnm-s Semdeg kodons (Tu da Ts mcire suberTeulSi (30s) xdeba cilovani faqtorebis, evkariotebSi i-rnm-s dakavSireba (sainiciacio TF-1 da TF-2 faqtorebis daxmarebiT). cilovani F3 faqtoris daxmarebiT) formilmeTionini Tavisi sat-rnm- sainiciacio aug tripletTan da dan gadaitaneba meore aminomJava warmoiqmneba kompleqsi. F1 saini- alaninTan. i-rnm da sat-rnm maTTan ciacio faqtorTa monawileobiT dakavSirebuli formilmeTionin-ala formilmeTioninis sat-rnm ukavSir- niniT gadadian aqceptorul ubnebSi deba aug kodons, xolo F2 cilo- Tavisufali sat-rnm-s donoris vani faqtori ganapirobebs 50s adgilze. am procesis mravaljerad ribosomuli suberTeulis 30s-Tan ganmeorebisas polipeptiduri jaWvi SeerTebas srulyofili ribosomis TandaTan izrdeba. warmosaqmnelad (sur. 4.20). evka- riotebSi cilovan sainiciacio 4. terminacia. elongaciis procesSi faqtorebs warmoadgens M1, M2, M3. warmoiqmneba kompleqsi, romelSic dasrulebuli polipeptiduri jaWvi radgan ribosomas gaaCnia mxolod mierTebulia sat-rnm-Tan. radgan 2 (A-aminoaciluri da P-peptiduri) Semdgom uaa kodoni gvauwyebs sin- ubani 2 sat-rnm-s dasakavSireblad, Tezis damTavrebas, aqceptorul amitom cilis jaWvis gagrZeleba ubanSi aRar uerTdeba sat-rnm. (elongacia) xdeba sakmaod rTuli garkveul faqtorTa monawileobiT ciklis mravaljer ganmeorebiT. polipeptiduri jaWvi da sat-rnm genis moqmedebis molekuluri meqanizmebi 117 suraTi 4.20 iniciacia a u g g c u u c u a u g g c u u c u 1 2 a u g g c u u c u a u g g c u u c u u a c u a c f-meT f-meT 3 elongacia 4 a u g g c u u c u a u g g c u u c u a u g g c u u c u u a c c g a u a c c g a c g a a g a u a c f-meT ala ala ser ala f-meT f-meT 5 terminacia 6 7 g c u u a a g c u u a a g c u u a a c g a c g a ala arg ala arg 8 9 10 1-4 – iniciacia; 30s ribosomis suberTeuli uerTdeba i-rnm-s, sadac aug tri pletia. formilmeTioninis sat-rnm ukavSirdeba kodon aug-s. 50s: suberTeulis mierTebis Sedegad miiReba srulyofili ribosoma. cilovani sainiciacio faqtorebia prokariotebSi – F3, F2, F1; evkariotebSi – M1 M2 M 3. 5-7 - elongacia; sat-rnm ukavSirdeba i-rnm-s kodons – cu formilmeTionini gadadis Tavisi sat-rnm-dan meore aminomJavaze – alaninze. i-rnm, sat-rnm da formilmeTioninalanini gadadis aqceptorul ubanSi Tavisufali donoris ubanze. es etapebi mravaljer meordeba. elongaciis prokariotebis cilovani faqtorebi aris Th da Ts; evkariotebis – TF-1, TF-2. 8-10 - terminacia; radgan Semdegi kodoni uaa miuTiTebs sinTezis damTavrebaze, aqceptoruli ubani ar ierTebs araviTar sat-rnm-s (Hestca, 1971) 118 Tavi 4 adamianis genetika scildeba ribosomebs. zogadad Si - N-meTionins. Semdgom es aminomJavebi aseTi saxiT xdeba transkrifciisa fermentebiT amoiWreba da isini ver da translaciis (cilis sinTezi) xvdebian cilis SemadgenlobaSi. saini_ procesebi, romlebic pro-da ciacio kompleqsis Camoyalibebisas evkariotebSi ZiriTadad msgavsad xorcieldeba suberTeulebis gaerTianeba mimdinareobs. da P da A ubnebis Senebis dasruleba. prokariotebSi sastarto kodoni akodirebs N-forilmeTionins, evkarioteb- daskvna adamianis genomis sidide Seesabameba 3x109 nukleotidur Tanamimdevrobas, anu 3 miliard bass, anu 3 milion kb (kilobasi), anu 3000 mb (megabasi). makodirebel genTa raodenoba, romlebic ganapirobeben cilis, aratranslirebad ribosomul da satransporto rnm-s sinTezs, ganisazRvreba ≈ 4·104 geniT. genomis makodirebeli nawili - egzonebi aris totaluri dnm-s mxolod 1%, genomis aramakodirebeli nawili - intronebi - 24%, danarCeni dnm – 75%. dnm-s nukleotiduri Tanamimdevrobis pirveladi – `tripleturi kodi“. dnm-s nukleotidur TanamimdevrobaTa meoreuli kodi - `qromatinis kodi“” gansazRvravs, rom adeninis nukleotidTa ganlageba axdens dnm-s spiralis histonuri kompleqsis irgvliv daxvevis mimarTulebis kodirebas. qromosomaTi dnm-s nukleotidur TanamimdevrobaTa mesameuli kodi -`qromatinis kondensaciis kodi“, rogorc aRiniSna, arahistonuri cilebi Ca++ ionebiT moqmedebisas da fosforilirebis Sedegad iwvevs dnm-s lokus-specifikur daxvevas da lokus-specifikuri qromatinuli struqturis kodirebas birTvSi. genetikis nawils, romelic Seiswavlis cocxal organizmTa mTlian genomebs, ewodeba genomika. genomikis kvlevis mizans warmoadgens ama Tu im organizmis ujredebSi dnm-s nukleotidur Tana- mimdevrobaTa Seswavla. prokariotebSi (baqteriebSi) genetikuri regulaciis erTeuli - operoni warmoadgens genTa kompleqss, romelic ganapirobebs genetikuri sistemis regulacias. operonis SemadgenlobaSi arsebu- li kompleqsis detalurma analizma daadgi

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