KDM2b/JHDM1b directly regulates p15^Ink4b expression in leukemic cells. (A) RT-qPCR analysis shows that p15^Ink4b is significantly up-regulated in response to Kdm2b/Jhdm1b KD. Relative mRNA levels are measured by RT-qPCR and normalized to Gapdh level. (B) Schematic representation of the p15^Ink4b locus in mouse, indicating the genomic structure (exons are represented by black boxes), as well as the location of the 3 amplicons analyzed by ChIP assays. (C) ChIP experiments with chromatin prepared from leukemic cells expressing LacZ-Flag, wild-type KDM2b/JHDM1b-Flag, and mutant KDM2b/JHDM1b-Flag were carried out with the use of anti-Flag antibody. KDM2b/JHDM1b-Flag binding was assayed by qPCR at the 3 genomic regions depicted in panel B. (D) ChIP experiments with chromatin prepared from leukemic cells with control KD, Kdm2b/Jhdm1b KD, Kdm2b/Jhdm1b KD reconstituted with wild-type Kdm2b/Jhdm1b or mutant Kdm2b/Jhdm1b were carried out with the use of the anti-H3K36me2 antibody. H3K36me2 level was assayed by qPCR at the 3 genomic regions depicted in panel B.