Two DNA binding domains of MGA act in combination to suppress ectopic activation of meiosis-related genes in embryonic stem cells

PRC1.6, one of non-canonical PRC1 is known to function as a safeguard preventing precocious and ectopic onset of meiosis in germ cells and ESCs, respectively. Since disruption of PRC1.6 may be directly linked to embryonic lethality and infertility, it is important to uncover the detailed molecular bases of PRC1.6 function. Here, we addressed this issue by characterizing MGA, one of essential component of the complex. Our data revealed that MGA functions to repress numerous genes, in particular meiosis-related genes by using two DNA binding domains that MGA bears exquisitely. Our data also identified MEIOSIN as a linchpin molecule in the transition from negative to positive regulation on meiotic onset.