DIFFERENTIAL EXPRESSION PATTERNS OF THE PEA3 GROUP TRANSCRIPTION FACTORS THROUGH MURINE EMBRYONIC-DEVELOPMENT

ERM, ER81 and PEA3 are three highly related transcription factors belo nging to the ETS family. Together they form the PEA3 group within this family. Little data is yet available regarding the roles of these thr ee genes during embryonic development. A prerequisite to investigation s in this field is to obtain an accurate spatio-temporal expression ma p for the erm, er81 and pea3 genes. To this end, we have used in situ hybridization to compare their expression patterns during critical sta ges of murine embryogenesis. We report that all three genes are expres sed in numerous developing organs coming from different embryonic tiss ues. The three genes appeared co-expressed in different organs but pre sented specific sites of expression, so that the resultant expression pattern could in fact reveal several distinct functions depending upon isolated and/or various combinations of the PEA3 member expression. T hese results suggest that erm, er81 and pea3 genes are differentially regulated, probably to serve important functions as cell proliferation control, tissue interaction mediator or cell differentiation, all ove r successive steps of the mouse organogenesis.