Description
c-Myc is one of key players that are crucially involved in maintaining the undifferentiated state and the self-renewal of ESCs. To understand the mechanism by which c-Myc helps preserve these prominent characteristics of ESCs, we generated null-ES cells for the Max gene, which encodes the best characterized partner protein for all Myc family proteins. Although Myc/Max complexes have been widely regarded as crucial regulators of the ESC status, our data reveal that ESCs do not absolutely require these complexes in so-called ground state or related conditons and that this requirement is restricted to conventional ES culture conditions without using a MAPK inhibitor.