The developmental fate of green fluorescent mouse embryonic germ cells in chimeric embryos

Primordial germ cells (PGCs), as precursors of mam-malian germ lineage, have been gaining more attention as anew resource of pluripotent stem cells, which bring a greatpossibility to study developmental events of germ cell invitro and at animal level. EG4 cells derived from 10.5 dayspost coitum (dpc) PGCs of l29/svJ strain mouse wereestablished and maintained in an undifferentiated state.With an attempt to study the differentiation capability ofEG4 cells with a reporter protein: green fluorescence pro-tein, and the possible application of EG4 cells in the re-search of germ cell development, we have generated severalEG4-GFP cell lines expressing enhanced green fluorescenceprotein (EGFP) and still maintaining typicaI characteris-tics of pluripotent stem cells. Then, the differentiation ofEG4-GFP cells in vitro as well as their developmental fatein chimeric embryos which were produced by aggregatingEG4-GFP cells to 8-cell stage embryos were studied. Theresults showed that EG4 cells carrying green fluorescencehave a potential use in the research of germ cell develop-ment and other related studies.