Biochemistry 2280A Study Guide - Final Guide: Hbb, Spliceosome, Intron

• School: Western University
• Department: Biochemistry
• Course: Biochemistry 2280A
• Professor: Chris Brandl

Document Summary

Introns are removed in two consecutive transesterfication reactions. Branch point: attack by 2" oh of sugar (adenine) attacks the 5" splice junction, frees 5" exon. Attack by 3" oh of the free 5" splice junction with the 3" splice junction: reform back bone, release lariat thing. The spliceosome is the enzymatic machinery for splicing. Composed of snrnps which contain both rna and protein (u1,u2,u4,u5,u6) Spliceosome holds everything in place so splicing can happen. Through rna-rna and protein-protein interaction, the spliceosome positions the rna for splicing + catalyzes reaction. U2 and u1 snrnps that recognize the splice junction. Recognition of right sequences through rna-rna interactions. Gave rise to idea of catalytic rnas. Rna and the origins of life 253-256. Abnormal splicing of the beta-globin rna can result in hemoglobin deficiency. Some diseases in mutations for things in splicing (up) Normal adult beta globin primary transcript (diagram) Some mutations in introns that give rise to disease.