Comparative expression analysis of the antagonistic transcription factors EVI1 and MDS1-EVI1 in murine tissues and during in vitro hematopoietic differentiation

An alternative form of the transcription factor EVI1, MDS1-EVI1, which prev iously had been believed to exist only in the context of leukemic fusion mR NAs, has recently been shown to be expressed also in normal human tissues. Moreover, it acts as an antagonist of EVI1, activating transcription of rep orter constructs repressed by EVI1, We cloned the murine homolog of MDS1-EV I1 as well as mMds1 and show localization of mMds1 close to mEvil on chromo some 3. Using RT-PCR, we demonstrate widespread expression of both Evil for ms in the adult mouse, as well as their upregulation during in vitro hemato poietic differentiation. Our data underscore the biological importance of b oth EVI1 and MDS1-EVI1 and provide the basis for further studies of their f unction in the mouse model system. (C) 1998 Academic Press.