Identification of mRNA species that code for extra-embryonic endodermal cytoskeletal proteins in differentiated derivatives of murine embryonal carcinoma cells.

The messenger RNA species that code for two extra-embryonic endodermal cytoskeletal proteins (Endo A and Endo B) have been identified. Endo A and Endo B messenger RNA species are differentially expressed. They are absent, or at basal levels, in undifferentiated embryonal carcinoma cells (F9.22 cell line) and relatively abundant in parietal endoderm (PFHR9 cell line) or in embryonal carcinoma cells that have been induced, by retinoid acid, to differentiate to parietal endoderm. Endo A and Endo B messenger RNA can be detected in F9.22 cells 48 to 72 h after exposure to retinoic acid, which is coincident with the expression of Endo A and Endo B proteins. The size of Endo A and Endo B messenger RNA has been determined by denaturing methyl mercury hydroxide agarose gels to be 2.0 +/- 0.1 and 1.5 +/- 0.2 kilobases, respectively.