BIOL 367 Chapter Notes - Chapter 13: Pcaf, Bromodomain, Taf1
Document Summary
Chapter 13 chromatin structure and its effects on. Chromatin is composed of dna and proteins, mostly basic proteins called histones that help chromatin fold so it can pack i(cid:374)to the ti(cid:374)y (cid:448)olu(cid:373)e of a cell"s (cid:374)ucleus. Most eukaryotic cells contain five different kinds of histones: Have a pronounced positive charge at neutral ph. Because of their basic nature, the histones migrate toward the cathode during non-denaturing electrophoresis, unlike most other proteins, which are acidic and therefore move towards the anode. Most of the histones are well conserved. However, higher resolution separations of the histones have revealed much greater variety. This variety stems sources: gene reiteration and posttranslational modification. The histone genes are repeated many times: 10-20 times in the mouse, and about 100 times in drosophila. The most common histone modification is acetylation, which can occur on n-terminal amino groups and on lysine -amino groups. Other modifications include lysine -amino methylation and phosphorylation.