The conserved adenine nucleotide in introns serves as the:
A)site for intron recognition for the spliceosome.
B)branch point for the formation of the intronic "lariat."
C)key point for ribosome assembly and initiation of translation.
D)initial site of intronic RNA digestion and removal.
E)molecular signal for RNA splicing.

Question

Quizplus · Accepted Answer

The conserved adenine nucleotide in introns serves as the branch point for the formation of the intronic "lariat." This is the intermediate structure that is formed during the splicing process and allows for the removal of introns from pre-mRNA. The other choices are not accurate - the site for intron recognition for the spliceosome is typically located at the ends of the intron rather than a specific nucleotide within the intron, the conserved adenine nucleotide is not involved in ribosome assembly or translation initiation, and it is not the initial site of intronic RNA digestion and removal (rather, the splicing process removes the introns). Finally, while the conserved adenine nucleotide does play an important role as a molecular signal for RNA splicing, it primarily functions as the branch point nucleotide rather than the signal itself.

The Conserved Adenine Nucleotide in Introns Serves as The