Question

A toxin found in a recently discovered mushroom interrupts the function of a human’s snRNP RNA known as U2. Answer the two questions below.

a. What specific U2 functions are disrupted? (2 points)

b. What complex would this ultimately terminate the assembly of?

Answer 1

A)U2 snRNA plays an important role in intron recognition during the splicing mechanism of post-transcriptional modification of pre-mRNA. The recognition occurs when a 7-12 nucleotide sequence of the RNA interacts with the upstream region of 3' splice site called the branch point sequence. The duplex formation between these 2 sequences lead to a conserved adenosine residue to bulge out. This residue then takes part in subsequent nucleophilic attack and transesterification reaction to finally splice out the intron.

So this complete process (specifically intron recognition and bulging of A residue)will be disrupted if U2 is disrupted.

B)This would ultimately terminate the assembly of splicosome which carry out the process of splicing.