RNA Splicing and Spliceosome Quiz

<p>They act as guards to ensure proper binding of pre-mRNA.</p> Signup and view all the answers

<p>They recruit spliceosome components to the 5′ end and 3′ splice sites.</p> Signup and view all the answers

<p>Exon skipping</p> Signup and view all the answers

<p>Recognition of distinct 5′ and 3′ splice sites</p> Signup and view all the answers

<p>Recognizes and binds to the 5’ splice site, the branch site, and the 3’ splice site, and catalyzes RNA cleavage and joining reactions</p> Signup and view all the answers

<p>Release a linear intron</p> Signup and view all the answers

<p>Self-splicing introns do not require the spliceosome and are usually shorter than Group II introns</p> Signup and view all the answers

<ol> <li>Transfer of splicing factors from RNA polymerase CTD to the 5′ splice site, poised &amp; ready to react with the next 3′ site. 2) Ensure that only splice sites next to exons are selected by SR proteins binding to Exonic Splicing Enhancers (ESE) and recruiting components of the splicing machinery.</li> </ol> Signup and view all the answers

<p>Trans-splicing is the fusion of exons from different RNA molecules, allowing exon skipping and alternative splicing. It differs from traditional splicing in that it can join exons that are not necessarily the nextmost ones or even from completely different mRNAs.</p> Signup and view all the answers

<p>The minor spliceosome recognizes distinct 5′ and 3′ splice sites but uses the same splicing process as the major spliceosome. It splices a small group of introns using a different set of snRNPs, providing more specificity in splicing.</p> Signup and view all the answers

<p>SR proteins (Serine-aRginine rich) bind to Exonic Splicing Enhancers (ESE) and recruit components of the splicing machinery to ensure accurate splicing. They help direct splicing to proper sites and reduce exon skipping.</p> Signup and view all the answers

<p>mRNA splicing is the process of removing intervening introns from pre-mRNA and joining the protein-encoding exons to form mature mRNA. This process is carried out by the spliceosome, a large complex consisting of 150 proteins and 5 RNAs, including U1, U2, U4, U5, and U6 snRNAs. The spliceosome recognizes and binds to the 5’ splice site, the branch site, and the 3’ splice site, and catalyzes RNA cleavage and joining reactions through sequential transesterification events. Alternative splicing can yield different proteins from the same gene, and the type of splicing determines if the spliceosome is needed, the branch site used, and the final intron type.</p> Signup and view all the answers

<p>It is believed that spliceosomes may have evolved from Group II self-splicing introns, as they share the same structure as spliceosome’s snRNPs. Group II introns are self-splicing introns that usually require a free G-site branch site, and they are well-conserved and usually shorter than other self-splicing introns. The similarities in structure and function between Group II introns and the spliceosome suggest a potential evolutionary relationship between the two.</p> Signup and view all the answers

<p>Splicing can yield different proteins from the same gene through alternative splicing, resulting in isoforms. This process allows for the production of multiple protein variants from a single gene, greatly increasing the proteomic diversity and functional complexity of eukaryotic organisms. As eukaryotic complexity increases, the intron content per gene also increases, indicating a potential relationship between splicing and the complexity of eukaryotic organisms.</p> Signup and view all the answers

<p>CRISPR/Cas9 is used to create knock-out or knock-in mutations by targeting specific DNA sequences for modification. Mutated Cas9 nucleases increase the possibilities of genetic engineering by allowing for more precise and diverse genetic alterations, but also raise concerns about off-target effects and unintended mutations.</p> Signup and view all the answers

<p>CRISPR Prime Editing greatly improves prospects for genetic surgery by enabling more precise and efficient modification of genetic material. This technology offers the potential for permanent human genetic alteration and has implications for treating genetic disorders and diseases.</p> Signup and view all the answers

<p>RNA splicing in eukaryotic genes involves the removal of introns and the joining of exons to form a mature mRNA molecule. This process is facilitated by the spliceosome and various splicing proteins, which work together to accurately remove introns and ligate exons. The fidelity of splicing is maintained through the coordination of these proteins, as well as the recognition of splice sites and the correction of splicing errors.</p> Signup and view all the answers