BIOCH330 Lecture Notes - Lecture 3: Snrnp, Spliceosome, Autocatalysis

• School: University of Alberta
• Department: Biochemistry
• Course: BIOCH330
• Professor: Andrew Macmillan

Document Summary

First discovered as part of cellular organelles. The splicing reaction requires mg2+ but no additional protein cofactor. An adenosine is conserved in grii introns. The 2"-oh of the a carries out the attack at a 5" splice site. 5"-exon attacks at the 3" splice site. Product: ligated exon and the lariat product. Proceeds through the same mechanism as grii system. Each snrnp contains and rna and associated proteins. Spliceosome is a rnp molecule: protein-rna assembly. But all snrnps have a shared set of proteins. Those are the so-called snrnp core proteins. The sm proteins are small proteins , look very similar and assemble into donut structure to associate with snrna. Sm core associates with a certain sequence called the sm box at the 3" end of the snrna. Sm proteins turn out to be proteins that stimulate antibody production in lupus patients.