In genetics, the 'Poly-A tail' is a sequence of adenine nucleotides added to the 3' end of eukaryotic mRNA. Its primary functions include: MCQ with Answer and Explanation
In genetics, the 'Poly-A tail' is a sequence of adenine nucleotides added to the 3' end of eukaryotic mRNA. Its primary functions include:
A. Protecting the mRNA from degradation by exonucleases and facilitating its export from the nucleus and translation
B. Initiating translation
C. Binding to the DNA template
D. Splicing out introns
Answer: Option A
Solution (By JKExamLibrary)
The poly-A tail is a long chain of adenine nucleotides (typically 100-250) added to the 3' end of a pre-mRNA molecule during post-transcriptional processing in the nucleus. Its primary functions are to protect the mRNA molecule from enzymatic degradation in the cytoplasm (by exonucleases), to facilitate the export of the mature mRNA from the nucleus to the cytoplasm, and to promote translation by helping to recruit ribosomes. It also plays a role in determining the lifespan of the mRNA in the cytoplasm.
Explanation:
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Explanation:
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Explanation:
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