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True or false:

The AAUAAA sequence found near the 3'-end of eukaryotic mRNA is required for both terminating the transcript and for polyadenylation.

User Meshu
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Final answer:

True, The AAUAAA sequence near the 3'-end of eukaryotic mRNA is indeed essential for transcript termination and polyadenylation, which protects the mRNA and regulates its stability.

Step-by-step explanation:

The statement that the AAUAAA sequence found near the 3'-end of eukaryotic mRNA is required for both terminating the transcript and for polyadenylation is true. This sequence serves as a signal for the cleavage of pre-mRNA, which precedes the addition of the poly(A) tail. Once elongation is complete, the pre-mRNA is cleaved by an endonuclease between an AAUAAA consensus sequence and a GU-rich sequence, which allows an enzyme called poly-A polymerase to add a string of about 200 adenine (A) residues. This polyadenylation results in a 3' poly(A) tail that protects the mRNA from degradation, assists in the nuclear export, and regulates the half-life of the mRNA in the cytoplasm.

User Mttcrsp
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