Introns in MRNA are Removed By

Question

Introns in mRNA are removed by:
A) The concerted action of a splicing endonuclease and Ligase
B) Autocatalytical splicing
C) Ribonucleoprotein structures called spliceosomes
D) All of these
E) none of these

Accepted Answer

Introns in mRNA are removed by ribonucleoprotein structures called spliceosomes. These spliceosomes consist of small nuclear RNAs (snRNAs) and proteins that form complexes and recognize specific site sequences at intron-exon boundaries. They carry out the actual cutting and splicing of the pre-mRNA to remove the introns and join together the exons.