Continual removal of H3K9 promoter methylation by Jmjd2 demethylases is vital for ESC self‐renewal and early development

Abstract

Chromatin-associated proteins are essential for the specification and maintenance of cell identity. They exert these functions through modulating and maintaining transcriptional patterns. To elucidate the functions of the Jmjd2 family of H3K9/H3K36 histone demethylases, we generated conditional Jmjd2a/Kdm4a, Jmjd2b/Kdm4b and Jmjd2c/Kdm4c/Gasc1 single, double and triple knockout mouse embryonic stem cells (ESCs). We report that while individual Jmjd2 family members are dispensable for ESC maintenance and embryogenesis, combined deficiency for specifically Jmjd2a and Jmjd2c leads to early embryonic lethality and impaired ESC self-renewal, with spontaneous differentiation towards primitive endoderm under permissive culture conditions. We further show that Jmjd2a and Jmjd2c both localize to H3K4me3-positive promoters, where they have widespread and redundant roles in preventing accumulation of H3K9me3 and H3K36me3. Jmjd2 catalytic activity is required for ESC maintenance, and increased H3K9me3 levels in knockout ESCs compromise the expression of several Jmjd2a/c targets, including genes that are important for ESC self-renewal. Thus, continual removal of H3K9 promoter methylation by Jmjd2 demethylases represents a novel mechanism ensuring transcriptional competence and stability of the pluripotent cell identity.

Jmjd2/Kdm4 demethylases are required for expression of Il3ra and survival of acute myeloid leukemia cells

“…Previously, we reported that Jmjd2a and Jmjd2c both localize to H3K4me3-positive TSSs in mouse embryonic stem cells (mESCs) (Pedersen et al 2014(Pedersen et al , 2016. Similar to what was observed for Jmjd2a and Jmjd2c in mESCs, we found a strong overlap in Jmjd2a-and Jmjd2c-binding patterns ( Fig.…”

“…Using this system in combination with knockout mouse strains that we generated (Pedersen et al 2016), we developed a mouse model of MLL-AF9 translocated AML that is conditionally knocked out for Jmjd2/Kdm4 activity. In cells from these mice, loxP sites are flanking critical exons in Jmjd2a, Jmjd2b, and Jmjd2c, and, in addition, an inducible form of Cre recombinase (CreERT2) is expressed from the Rosa26 locus (we refer to this mouse strain as 2abc;CreER).…”

“…Generation of Jmjd2a/b/c f/f ;Rosa26::CreERT2 mice is described in Pedersen et al (2016). B6.SJL mice were used as recipients in the transplantation experiments.…”

Advances in histone demethylase KDM4 as cancer therapeutic targets

“…The amplification of genes in this region may play an important role in the pathogenesis of PV and AML. While KDM4C is dispensable for the survival of MLL‐AF9 translocated AML, conditional Kdm4a/Kdm4b/Kdm4c triple‐knockout mice cause defects in the progression of AML, suggesting that KDM4 demethylases are required for survival of the AML …”

Allele‐Specific Inhibition of Histone Demethylases

“…Given that the members of the KDM family play pivotal roles in mammalian development, single and combined knockouts are often lethal . To elucidate biological functions of a specific isoform within a KDM subfamily, we surmised that KDM variants that act much like a wild‐type enzyme but are selectively inhibited by a designed molecule could constitute a powerful approach (Figure ).…”