Regulatory RNAs and Gene Regulation Quiz

<p>Eukaryotes have fewer protein-coding genes than originally predicted</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>True</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>False</p> Signup and view all the answers

<p>True</p> Signup and view all the answers

<p>True</p> Signup and view all the answers

<p>True</p> Signup and view all the answers

<p>True</p> Signup and view all the answers

<p>Regulatory RNAs serve as regulators of gene transcription and translation.</p> Signup and view all the answers

<p>Eukaryotic gene regulation involves the use of regulatory RNAs to alter gene transcriptional activity for the purpose of studying gene function and medical applications.</p> Signup and view all the answers

<p>RNA interference (RNAi) involves very short RNAs that can repress or silence genes with homology to these short RNAs, thereby inhibiting gene expression.</p> Signup and view all the answers

<p>Formerly believed to be 'junk DNA,' non-protein coding RNAs are now known to serve as the template for regulatory RNAs with important roles in gene regulation.</p> Signup and view all the answers

<p>The knowledge of regulatory RNAs can be exploited to experimentally alter gene transcriptional activity in order to study gene function and for medical purposes.</p> Signup and view all the answers

<p>DGCR8, Drosha, and Pasha</p> Signup and view all the answers

<p>Dicer recognizes the Drosha-cleaved pre-miRNA and cleaves off the terminal loop</p> Signup and view all the answers

<p>The Argonaute protein is the 'slicer' protein in the RISC complex, which pairs miRNA &amp; target mRNA for silencing</p> Signup and view all the answers

<p>RNAi can be exploited to artificially silence target genes</p> Signup and view all the answers

<p>Plants use RNAi to suppress viral genes by spreading siRNAs made from the viral genome</p> Signup and view all the answers

<p>MicroRNAs (miRNAs), Small interfering RNAs (siRNAs), Repeat-associated small interfering RNAs (rasiRNAs)</p> Signup and view all the answers

<p>They facilitate interactions with targets, denature the RNA, and allow it to bind to matching regions in mRNA or genome. They can recruit chromatin remodeling enzymes when targeted to the nucleus and modify promoters, leading to gene silencing.</p> Signup and view all the answers

<p>Each pre-miRNA is composed of 2 'arms' on either side of the hairpin’s loop within the primary miRNA. The primary miRNA (pri-miRNA) is a precursor made of hairpin RNA plus ssRNA sequence, cleaved by 'DROSHA' RNase to give hairpin precursor miRNA (pre-miRNA). Second RNase cleavage reaction by DICER liberates the mature miRNA sequences. miRNAs need to undergo post-transcriptional processing to activate them.</p> Signup and view all the answers

<p>RISC can recruit RDRP to make even more dsRNA precursor, which amplifies the RNAi signal.</p> Signup and view all the answers

<p>Each pre-miRNA has two arms, each of which may have their own targets. The 'seed region' (bases 2-9) has high complementarity to target RNA and can help identify targets. Pre-miRNAs can yield 1-2 miRNAs that bind complementary target regions. Pre-miRNA may be found in any part of an RNA molecule, including exons, introns, and leader sequences.</p> Signup and view all the answers

<p>DGCR8, Drosha, and Pasha</p> Signup and view all the answers

<p>Dicer recognizes the Drosha-cleaved pre-miRNA and cleaves off the terminal loop</p> Signup and view all the answers

<p>Plants use RNAi to suppress viral genes by spreading siRNAs made from the viral genome</p> Signup and view all the answers

<p>Argonaute protein is the 'slicer' protein in the RISC complex, which pairs miRNA &amp; target mRNA for silencing</p> Signup and view all the answers

<p>RNAi can be exploited to artificially silence target genes</p> Signup and view all the answers

<p>Regulatory RNAs serve as regulators of gene transcription and translation, and they have been exploited to experimentally alter gene transcriptional activity for studying gene function and medical purposes.</p> Signup and view all the answers

<p>RNA interference (RNAi) involves very short RNAs that can repress or silence genes with homology to these short RNAs. It can cause inhibition of gene translation, formation and destruction of double-stranded RNA, as well as binding of short RNAs to gene promoters to block them.</p> Signup and view all the answers

<p>Formerly believed to be 'junk DNA,' non-coding RNAs (ncRNAs) are now known to have regulatory roles in gene expression.</p> Signup and view all the answers

<p>The knowledge of regulatory RNAs can be exploited to experimentally alter gene transcriptional activity for studying gene function and for medical purposes.</p> Signup and view all the answers

<p>Eukaryotic gene regulation involves the use of regulatory RNAs that have been found to serve as regulators of gene transcription and translation. This knowledge has been exploited to experimentally alter gene transcriptional activity for studying gene function and medical purposes.</p> Signup and view all the answers

<p>The three main classes of small RNAs in eukaryotes are MicroRNAs (miRNAs), Small interfering RNAs (siRNAs), and Repeat-associated small interfering RNAs (rasiRNAs)</p> Signup and view all the answers

<p>MiRNAs are processed and activated through a 2-step nucelolytic processing. Drosha cuts the pri-mRNA to liberate pre-miRNA with help of a specificity subunit protein (Pasha a.k.a. DGCR8)</p> Signup and view all the answers

<p>The Argonaute protein in the RISC complex is responsible for matching interfering RNA with target in mRNA or genome. It can denature the RNA and allows it to bind to matching regions to interfere with gene expression.</p> Signup and view all the answers

<p>RNA-Dependent RNA Polymerase (RDRP) can be recruited by RISC and make even more dsRNA precursor which amplifies the RNAi process.</p> Signup and view all the answers

<p>Pre-miRNAs have two arms, each of which may have their own targets. They have a characteristic structure with a 'seed region' (bases 2-9) that has high complementarity to target RNA and can help identify targets.</p> Signup and view all the answers

<p>DGCR8, Drosha, and Pasha</p> Signup and view all the answers

<p>Dicer recognizes the Drosha-cleaved pre-miRNA and cleaves off the terminal loop</p> Signup and view all the answers

<p>Argonaute protein is the 'slicer' protein in the RISC complex, which pairs miRNA &amp; target mRNA for silencing</p> Signup and view all the answers

<p>Plants use RNAi to suppress viral genes by spreading siRNAs made from the viral genome</p> Signup and view all the answers

<p>RNA interference (RNAi) likely evolved as an ancient immune system used for gene regulation and can be exploited to artificially silence target genes</p> Signup and view all the answers

<p>RNAs can serve as regulators of gene transcription and translation, and RNAi uses very short RNAs to bind and shut off matching regions in target genes</p> Signup and view all the answers

<p>Drosha cleaves pri-mRNA to yield pre-mRNA containing upper stem + loop, and Dicer recognizes and cleaves off the terminal loop</p> Signup and view all the answers

<p>RNAs can serve as regulators of gene transcription and translation, and RNAi uses very short RNAs to bind and shut off matching regions in target genes</p> Signup and view all the answers

<p>RNAi can be exploited to artificially silence target genes and suppress viral genes in plants</p> Signup and view all the answers

<p>Eukaryotic gene regulation involves the use of RNAi and regulatory RNAs to control gene expression</p> Signup and view all the answers

<p>formerly believed to be 'junk DNA' is now known as template for non-protein coding RNAs</p> Signup and view all the answers

<p>RNA interference (RNAi)</p> Signup and view all the answers

<p>RNA interference (RNAi) is a well-used method of choice to suppress gene expression in model organisms to study gene function</p> Signup and view all the answers

<p>Can now exploit regulatory RNA knowledge to experimentally alter gene transcriptional activity to study gene function, medical purposes</p> Signup and view all the answers

<p>eukaryotes were originally predicted to have far more protein-coding genes based on genome size but were later found by genome analysis to have far fewer proteins</p> Signup and view all the answers

<p>RNAs can serve as regulators of gene transcription and translation</p> Signup and view all the answers

<p>The Argonaute protein in the RISC complex helps in the RNA interference process by binding to the short RNAs and leading to gene silencing</p> Signup and view all the answers

<p>RNA interference (RNAi) can cause inhibition of translation of gene, formation and destruction of dsRNA, and short RNA binding to gene’s promoter to block it</p> Signup and view all the answers

<p>Pre-miRNAs have a characteristic hairpin structure and this structure helps in identifying them and their target genes</p> Signup and view all the answers

<p>Dicer is the second RNA-cleaving enzyme involved in miRNA production</p> Signup and view all the answers

<p>RNA interference (RNAi) is a regulatory mechanism in eukaryotes that uses very short RNAs to bind and shut off matching regions in target genes. It plays an important role in development and antiviral defense. Examples include the importance of RNAi in C. elegans and plant (Arabidopsis) research.</p> Signup and view all the answers

<p>The three main classes of small RNAs in eukaryotes are MicroRNAs (miRNAs), Small interfering RNAs (siRNAs), and Repeat-associated small interfering RNAs (rasiRNAs). MiRNAs usually downregulate RNAs by translational repression and mRNA decay, siRNAs target RNAs for degradation as a cellular defense mechanism, and rasiRNAs downregulate transcription from repetitive regions.</p> Signup and view all the answers

<p>The components of the RNA-Induced Silencing Complex (RISC) include Argonaute-family proteins and small RNAs. RISC denatures the RNA and allows it to bind to matching regions in target genes, causing mRNA destruction or inhibiting translation. The Argonaute-family proteins facilitate interactions with targets.</p> Signup and view all the answers

<p>The process of miRNA biogenesis involves the cleavage of primary miRNA (pri-miRNA) by 'DROSHA' RNase to give hairpin precursor miRNA (pre-miRNA), which are then exported to the cytosol. Subsequent cleavage by DICER liberates the mature miRNA sequences.</p> Signup and view all the answers

<p>RNA-Dependent RNA Polymerase (RDRP) can be recruited by RISC and make even more dsRNA precursor, which amplifies the RNAi process. This enhances gene silencing by producing additional small RNAs to target and shut off matching regions in genes.</p> Signup and view all the answers

<p>Pre-miRNAs have two 'arms,' each of which may have their own targets. The 'seed region' (bases 2-9) has high complementarity to target RNA and helps identify targets. Pre-miRNAs may be found in any part of an RNA molecule, including exons, introns, and leader sequences.</p> Signup and view all the answers

<p>miRNAs need to undergo post-transcriptional processing, which involves cleavage by DICER and miRNA-specific RNase called Drosha/DGCR8. Once activated, miRNAs can bind complementary target regions and regulate gene expression.</p> Signup and view all the answers

<p>The RNA-Induced Silencing Complex (RISC) denatures the RNA and allows it to bind to matching regions in target genes. Perfect target matches cause mRNA destruction, while imperfect target matches inhibit translation. RISC proteins are needed to match interfering RNA with targets in mRNA or the genome.</p> Signup and view all the answers

<p>Argonaute-family proteins in the RISC complex facilitate interactions with target genes and can recruit chromatin remodelling enzymes when targeted to the nucleus. They also modify promoters, leading to gene silencing. Additionally, they can function as &quot;Slicer&quot; proteins, causing mRNA cleavage.</p> Signup and view all the answers

<p>Small RNAs derived from different sources can be used to silence genes through translational repression, mRNA decay, and mRNA destruction. The different pathways include gene silencing through MicroRNAs (miRNAs), Small interfering RNAs (siRNAs), and Repeat-associated small interfering RNAs (rasiRNAs).</p> Signup and view all the answers