The H3K36 demethylase Jhdm1b/Kdm2b regulates cell proliferation and senescence through p15(Ink4b).
The Ink4a-Arf-Ink4b locus has a crucial role in both cellular senescence and tumorigenesis. JmjC domain-containing histone demethylase 1b (Jhdm1b, also known as Kdm2b and Fbxl10), the mammalian paralog of the histone demethylase Jhdm1a (also known as Kdm2a and Fbxl11), has been implicated in cell-cycle regulation and tumorigenesis. In this report, we show that Jhdm1b is a histone H3 lysine 36 (H3K36) demethylase. Knockdown of Jhdm1b in primary mouse embryonic fibroblasts inhibits cell proliferation and induces cellular senescence in a pRb- and p53 pathway-dependent manner. Notably, the effect of Jhdm1b on cell proliferation and cellular senescence is mediated through derepression of p15(Ink4b), as loss of p15(Ink4b) function rescues cell-proliferation defects in Jhdm1b-knockdown cells. Chromatin immunoprecipitation on ectopically expressed Jhdm1b demonstrates that Jhdm1b targets the p15(Ink4b) locus and regulates its expression in an enzymatic activity-dependent manner. Alteration of Jhdm1b level affects Ras-induced neoplastic transformation. Collectively, our results indicate that Jhdm1b is an H3K36 demethylase that regulates cell proliferation and senescence through p15(Ink4b).
Howard Hughes Medical Institute, Chapel Hill, North Carolina 27599-7295, USA.
Jin
J
He
Eric M
EM
Kallin
Yu-Ichi
Y
Tsukada
Yi
Y
Zhang
D000818:Animals; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000502:physiology*; D050762:Cyclin-Dependent Kinase Inhibitor p15 / Q000235:genetics / Q000378:metabolism*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000235:genetics / Q000378:metabolism; D044783:F-Box Proteins / Q000235:genetics / Q000378:metabolism*; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D006657:Histones / Q000378:metabolism; D006801:Humans; D056484:Jumonji Domain-Containing Histone Demethylases; D051379:Mice; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism
C417743:Cdkn2a protein, mouse; C493968:Cdkn2b protein, mouse; D050762:Cyclin-Dependent Kinase Inhibitor p15; D019941:Cyclin-Dependent Kinase Inhibitor p16; D044783:F-Box Proteins; D006657:Histones; D020033:Protein Isoforms; D056484:Jumonji Domain-Containing Histone Demethylases; C524747:Kdm2b protein, mouse; D018631:ras Proteins