Explain the processing of heterogeneous nuclear RNA (hnRNA) into a fully functional mRNA in eukaryotes. Where does this processing occur in the cell?
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Solution and Explanation
The processing of hnRNA into mRNA in eukaryotes involves the following steps:
- Capping: A methyl guanosine cap is added to the 5’ end of hnRNA, ensuring stability and aiding in ribosome recognition.
- Tailing: A poly-A tail is added to the 3’ end of hnRNA to prevent degradation and enhance translation.
- Splicing: Introns (non-coding regions) are removed, and exons (coding regions) are joined together to form a functional mRNA. This processing occurs in the nucleus of eukaryotic cells.
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