Editing Histone (section)

=== Yeast ===
Yeast carry one or two copies of each histone gene, which are not clustered but rather scattered throughout chromosomes. Histone gene transcription is controlled by multiple gene regulatory proteins such as transcription factors which bind to histone promoter regions. In budding yeast, the candidate gene for activation of histone gene expression is SBF. SBF is a transcription factor that is activated in late G1 phase, when it dissociates from its repressor [[Whi5]]. This occurs when [[Whi5]] is phosphorylated by Cdc8 which is a G1/S Cdk.<ref>{{cite journal | vauthors = de Bruin RA, McDonald WH, Kalashnikova TI, Yates J, Wittenberg C | title = Cln3 activates G1-specific transcription via phosphorylation of the SBF bound repressor Whi5 | journal = Cell | volume = 117 | issue = 7 | pages = 887–98 | date = June 2004 | pmid = 15210110 | doi = 10.1016/j.cell.2004.05.025 | doi-access = free }}</ref>   Suppression of histone gene expression outside of S phases is dependent on Hir proteins which form inactive chromatin structure at the locus of histone genes, causing transcriptional activators to be blocked.<ref>{{cite journal | vauthors = Xu H, Kim UJ, Schuster T, Grunstein M | title = Identification of a new set of cell cycle-regulatory genes that regulate S-phase transcription of histone genes in Saccharomyces cerevisiae | journal = Molecular and Cellular Biology | volume = 12 | issue = 11 | pages = 5249–59 | date = November 1992 | pmid = 1406694 | pmc = 360458 | doi = 10.1128/mcb.12.11.5249 }}</ref><ref>{{cite journal | vauthors = Dimova D, Nackerdien Z, Furgeson S, Eguchi S, Osley MA | title = A role for transcriptional repressors in targeting the yeast Swi/Snf complex | journal = Molecular Cell | volume = 4 | issue = 1 | pages = 75–83 | date = July 1999 | pmid = 10445029 | doi = 10.1016/S1097-2765(00)80189-6 | doi-access = free }}</ref>