Question

Splicing of eukaryotic mRNAs involves a macromolecular complex spliceosome, which consists of a variety of proteins and a number of distinct ribonucleoprotein particles. The small nuclear RNAs in the spliceosome play a critical role in splicing processes, whereas the proteins play different functions. ___________functions is not played by the proteins of the spliceosome.

Answer 1

Spliceosomal proteins are not involved in the editing of mRNAs, which is a distinct process that modifies the nucleotide sequence of an mRNA post-synthesis to potentially produce different protein variants.

Step-by-step explanation:

The proteins of the spliceosome do not play a role in the editing of mRNAs. This is a separate process that alters the nucleotide sequence of an mRNA after it has been synthesized, sometimes resulting in different protein products from the same mRNA sequence.

Spliceosomes are critical for the splicing process in eukaryotic cells, which involves the precise removal of introns from pre-mRNA transcripts and the reconnection of exons. Spliceosomes are composed of proteins and snRNAs that recognize the intron sequences and facilitate splicing. The main function of the spliceosomal proteins includes the proper assembly and stabilization of spliceosome components, aiding in the recognition of splice sites, and catalyzing the chemical reactions that result in the cleavage of introns and ligation of exons. RNA editing, on the other hand, can modify nucleotides within an mRNA, which is a distinct process and not a function of spliceosomal proteins. RNA splicing must be very precise, as even a single nucleotide error can disrupt the reading frame and lead to dysfunctional proteins.