Phosphorylation of Swi6/HP1 regulates transcriptional gene silencing at heterochromatin.
Heterochromatin protein 1 (HP1) recruits various effectors to heterochromatin for multiple functions, but its regulation is unclear. In fission yeast, a HP1 homolog Swi6 recruits SHREC, Epe1, and cohesin, which are involved in transcriptional gene silencing (TGS), transcriptional activation, and sister chromatid cohesion, respectively. We found that casein kinase II (CK2) phosphorylated Swi6. Loss of CK2-dependent Swi6 phosphorylation alleviated heterochromatic TGS without affecting heterochromatin structure. This was due to the inhibited recruitment of SHREC to heterochromatin, accompanied by an increase in Epe1. Interestingly, loss of phosphorylation did not affect cohesion. These results indicate that CK2-dependent Swi6 phosphorylation specifically controls TGS in heterochromatin.
Shimada
Atsushi
A
Laboratory of Signal Transduction, Department of Cell Biology, Institute for Virus Research, Kyoto University, Kyoto, Kyoto 606-8507, Japan.
Dohke
Kohei
K
Sadaie
Mahito
M
Shinmyozu
Kaori
K
Nakayama
Jun-Ichi
J
Urano
Takeshi
T
Murakami
Yota
Y
D047390:Casein Kinase II / Q000235:genetics / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D015966:Gene Expression Regulation, Fungal; D020868:Gene Silencing / Q000502:physiology*; D006570:Heterochromatin / Q000378:metabolism*; D010766:Phosphorylation; D012568:Schizosaccharomyces / Q000235:genetics / Q000378:metabolism*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism*
D002868:Chromosomal Proteins, Non-Histone; D006570:Heterochromatin; D029702:Schizosaccharomyces pombe Proteins; C465958:Swi6 protein, S pombe; D047390:Casein Kinase II; C479661:casein kinase II, S pombe