Expression pattern of c-sis, c-fos and c-jun in human placenta and embryofetal organs.

The expression pattern of c-sis, c-fos and c-jun was investigated in placenta and embryofetal organ specimens from the first trimester. Northern analysis of the placentae showed c-sis transcripts and c-fos expression. Northern analysis of the same genes in embryofetal organs pointed to the brain as the only organ where consistent transcriptional activity could be observed. RT-PCR analysis of c-fos and c-jun in placentae, staged at four different time periods in pregnancy, allowed to detect the expected fragments in all cases. The same was true when c-fos and c-jun were analyzed at the 13th week of gestation in all the embryofetal organs.