rRNA processing involves a series of steps to generate mature ribosomal RNA molecules, essential for protein synthesis. This process includes trimming, degradation, and modification of precursor rRNA transcripts.
Here's a breakdown of the rRNA processing steps, primarily focusing on the information provided:
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5.8S rRNA Processing: The initial 3' end processing of 5.8S rRNA involves trimming by the enzymes Rex1 and Rex2. This is followed by Trf4-mediated polyadenylation.
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25S rRNA Processing: The 3' end of 25S rRNA is formed through sequential digestion by four Rex proteins.
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18S rRNA Quality Control: Intermediates with an extended A1 site are generated during the 5' degradation of aberrant 18S rRNA precursors, indicating a quality control mechanism for removing faulty transcripts.
In summary, rRNA processing is a complex pathway involving multiple enzymes and steps to ensure the production of functional rRNA molecules. It includes trimming, polyadenylation, degradation of aberrant transcripts, and specific enzyme-mediated digestion.
