Chaperone control of the activity and specificity of the histone H3 acetyltransferase Rtt109.

Authors:Jeffrey Fillingham, Judith Recht, Andrea C Silva, Bernhard Suter, Andrew Emili, Igor Stagljar, Nevan J Krogan, C David Allis, Michael-Christopher Keogh, Jack F Greenblatt
Language:Eng.
Date:16-06-2008
Journal:Molecular and cellular biology (1098-5549)
Release:Mol Cell Biol. 2008 Jul;28(13):4342-53


Abstract:



Acetylation of Saccharomyces cerevisiae histone H3 on K56 by the histone acetyltransferase (HAT) Rtt109 is important for repairing replication-associated lesions. Rtt109 purifies from yeast in complex with the histone chaperone Vps75, which stabilizes the HAT in vivo. A whole-genome screen to identify genes whose deletions have synthetic genetic interactions with rtt109Delta suggests Rtt109 has functions in addition to DNA repair. We show that in addition to its known H3-K56 acetylation activity, Rtt109 is also an H3-K9 HAT, and we show that Rtt109 and Gcn5 are the only H3-K9 HATs in vivo. Rtt109's H3-K9 acetylation activity in vitro is enhanced strongly by Vps75. Another histone chaperone, Asf1, and Vps75 are both required for acetylation of lysine 9 on H3 (H3-K9ac) in vivo by Rtt109, whereas H3-K56ac in vivo requires only Asf1. Asf1 also physically interacts with the nuclear Hat1/Hat2/Hif1 complex that acetylates H4-K5 and H4-K12. We suggest Asf1 is capable of assembling into chromatin H3-H4 dimers diacetylated on both H4-K5/12 and H3-K9/56.

Copyright:Molecular and cellular biology

Banting and Best Department of Medical Research, Terrence Donnelly Centre for Cellular and Biomolecular Research (CCBR), University of Toronto, 160 College St., Toronto, Ontario M5S 3E1, Canada.
Full text:
EBSCO - HTML (needs subscription)
HighWire Press - HTML (needs subscription)
 
Add to my archiveAdd to my archive


Send to a friendSend to a friend
Molecular and cellular biology