Warning: Undefined variable $zfal in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 525
Deprecated: str_replace(): Passing null to parameter #3 ($subject) of type array|string is deprecated in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 525
Warning: Undefined variable $sterm in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 530
free
Warning: Undefined variable $sterm in C:\Inetpub\vhosts\kidney.de\httpdocs\mlpefetch.php on line 531
free free
English Wikipedia
Nephropedia Template TP (
Twit Text
DeepDyve Pubget Overpricing |
lüll Silent information regulator 3: the Goldilocks of the silencing complex Norris A; Boeke JDGenes Dev 2010[Jan]; 24 (2): 115-22A recent explosion of work surrounds the interactions between Sir3p (Silent Information Regulator 3) and chromatin. We review here the Sir3p functions related to its role in silencing in Saccharomyces cerevisiae. This unusual protein, which is absolutely required for silencing, is distantly related to the highly conserved replication initiator Orc1p, but is itself phylogenetically limited to "post-genome-duplicated" budding yeasts. Several recent studies revise earlier models for Sir3p action. Specifically, the N-terminal bromo-adjacent homology (BAH) domain plays a now well-defined role in silencing, and a picture is emerging in which both termini of Sir3p bind two locations on the nucleosome: (1) the loss of ribosomal DNA silencing (LRS) surface in the nucleosome core, and (2) the N-terminal histone tails for effective silencing at telomeres. We relate Sir3p structure and function, and summarize recent molecular studies of Sir3p/chromatin binding, Sir3p/Dot1p competition, and the possible role of O-Acetyl ADP ribose (O-AADPR) in Sir3p/chromatin binding. We emphasize recent genetic data that provide important new insights and settle controversies created by in vitro work. Finally, we synthesize these ideas to revise the model for how Sir3p mediates silent chromatin formation in yeast, in part through its affinity for the LRS region of the nucleosome, which must be "just right."|*Gene Silencing[MESH]|Chromatin/metabolism[MESH]|Histone-Lysine N-Methyltransferase/metabolism[MESH]|Models, Molecular[MESH]|Nuclear Proteins/metabolism[MESH]|O-Acetyl-ADP-Ribose/metabolism[MESH]|Protein Structure, Tertiary[MESH]|Saccharomyces cerevisiae Proteins/metabolism[MESH]|Saccharomyces cerevisiae/*genetics/*metabolism[MESH]|Silent Information Regulator Proteins, Saccharomyces cerevisiae/*metabolism[MESH]|Static Electricity[MESH]|Telomere/genetics[MESH] |