Riboswitches
35 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which enzyme is involved in the riboflavin biosynthesis pathway and is regulated by a FMN riboswitch?

  • RibA
  • RibCF
  • RibH
  • RibE (correct)

    • What is the role of GTP cyclohydrolase II (RibA) in the riboflavin biosynthesis pathway?

  • Inhibits the formation of FMN riboswitch
  • Catalyzes an early step in the pathway (correct)
  • Regulates the expression of RibE
  • Is not involved in the pathway

    • What happens when FMN binds to the riboswitch?

  • Inhibits translation only
  • Causes premature termination of gene expression (correct)
  • Stimulates gene expression
  • Has no effect on gene expression

    • Which genes are part of the single transcription unit regulated by the FMN riboswitch?

    <p>ribDG-E-AB-H</p> Signup and view all the answers

    What is the utility of the FMN riboswitch in the pathogenic bacterium M. tuberculosis?

    <p>Controls riboflavin biosynthesis pathway</p> Signup and view all the answers

    Which statement accurately describes the effect of FMN binding to its target?

    <p>Results in a conformational change and formation of a terminator/sequester loop</p> Signup and view all the answers

    Which analogs inhibit the synthesis of vitamin B2 and FMN?

    <p>Roseoflavin and Ribocil-C</p> Signup and view all the answers

    What is the effect of inhibitors of FMS synthesis on the pathogenic bacterium M. tuberculosis?

    <p>Act as antibiotics</p> Signup and view all the answers

    What happens in the absence of FMN?

    <p>mRNA is produced and translated</p> Signup and view all the answers

    Which enzyme catalyzes the formation of 3,4-dihydroxy2-butanone-4-phosphate in the riboflavin biosynthesis pathway?

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

    Which type of gene expression regulation will be discussed in today's lecture?

    <p>Post-transcriptional</p> Signup and view all the answers

    What is the key benefit of posttranscriptional control of gene expression?

    <p>Rapid protein synthesis</p> Signup and view all the answers

    Which example is used to illustrate regulation via translational feedback?

    <p>The r-protein operons</p> Signup and view all the answers

    What is the main focus of the article 'Antibiotic Resistance: Current Perspectives'?

    <p>Antibiotic resistance</p> Signup and view all the answers

    In bacteria, what is increased demand for protein synthesis met by?

    <p>Increasing the number of ribosomes</p> Signup and view all the answers

    Which factor operates at the transcriptional and translational level to regulate riboflavin biosynthesis?

    <p>RibB FMN riboswitch</p> Signup and view all the answers

    What was discussed in the last lecture regarding gene expression regulation in bacteria?

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

    Which operon was mentioned in the last lecture for positive and negative regulation with different proteins?

    <p>lac operon</p> Signup and view all the answers

    What is the source of the article 'The ribB FMN riboswitch from Escherichia coli'?

    <p>FEBS Journal</p> Signup and view all the answers

    Which section of the text should be referred to for further details on post-transcriptional regulation of gene expression?

    <p>20.2.1 – 20.2.2</p> Signup and view all the answers

    What percentage of total cellular proteins can ribosomal proteins make up in rapidly growing cells?

    <p>45%</p> Signup and view all the answers

    How many genes encode r-proteins?

    <p>52</p> Signup and view all the answers

    Where do riboswitches exist within mRNA?

    <p>5′ untranslated region (5′UTR)</p> Signup and view all the answers

    What controls gene expression by inhibiting translation when [vitamin B1] is high?

    <p>Thiamine pyrophosphate (TPP)–binding riboswitch</p> Signup and view all the answers

    Which molecule causes the glmS riboswitch to degrade itself?

    <p>GlcN6-P</p> Signup and view all the answers

    How are riboswitches classified?

    <p>Based on ligand type and secondary structure</p> Signup and view all the answers

    What is one of the mechanisms through which many bacteria are developing resistance to antibiotics?

    <p>Increasing antibiotic efflux</p> Signup and view all the answers

    Which riboswitch controls the expression of genes involved in the biosynthesis of riboflavin (vitamin B2)?

    <p>FMN riboswitch</p> Signup and view all the answers

    What is the function of one r-protein in each operon?

    <p>Transcriptional repressor</p> Signup and view all the answers

    What is the role of riboswitch-regulated mRNAs' long sequences upstream from the translation start site?

    <p>Forming the riboswitch</p> Signup and view all the answers

    True or false: The FMN riboswitch is involved in the regulation of the riboflavin biosynthesis pathway in M. tuberculosis.

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

    True or false: In the presence of FMN, gene expression is prematurely terminated due to the binding of FMN to the riboswitch.

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

    True or false: Roseoflavin and Ribocil-C promote the synthesis of vitamin B2 and FMN.

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

    True or false: The FMN riboswitch only regulates transcription and not translation.

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

    True or false: The ribDG-E-AB-H transcriptional unit is regulated by the FMN riboswitch.

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

    Study Notes

    Riboswitches and Antibiotic Resistance

    • Ribosomal proteins can make up to 45% of total cellular proteins in rapidly growing cells
    • Bacteria coordinate the synthesis of the ribosomal components r-proteins r-RNAs
    • There are 52 genes encoding r-proteins, present in ~20 operons, with one r-protein in each operon functioning as a translational repressor
    • Riboswitches exist within the 5′ untranslated region (5′UTR) of mRNA and can function at the level of transcription and translation
    • The thiamine pyrophosphate (TPP)–binding riboswitch controls gene expression by inhibiting translation when [vitamin B1] is high
    • Riboswitches can affect mRNA stability, such as the glmS riboswitch which degrades itself on binding of GlcN6-P
    • Riboswitches can discriminate between chemically related molecules based on atomic charge, stereochemistry, and the presence or absence of particular functional groups
    • Riboswitches can be very specific to their ligands
    • Riboswitch-regulated mRNAs have unusually long sequences upstream from the translation start site that are necessary to form the riboswitch
    • There are over 15 classes of Riboswitches, classified based on ligand type and secondary structure
    • Many bacteria are developing resistance to antibiotics through mechanisms such as decreasing antibiotic influx, increasing antibiotic efflux, degrading or modifying antibiotics, protecting antibiotic targets, and producing alternative proteins
    • The FMN riboswitch controls the expression of genes involved in the biosynthesis of riboflavin (vitamin B2) and is related to antibiotic resistance through the inhibition of vitamin B2 and FMN synthesis.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    BIOL 366 Lecture 14: Post Transcriptional Regulation PDF

    Description

    Test your knowledge of riboswitches and antibiotic resistance with this quiz. Explore the role of ribosomal proteins, riboswitch functions, and bacterial resistance mechanisms. From the classification of riboswitches to the impact on antibiotic targets, delve into the intricate world of cellular regulation and drug resistance.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser