Figure 3.

Transcripts encoding molecules that can antagonize the effects of BMP-2 and BMP-4 are present in the fetal bowel. RT-PCR was used to detect transcripts encoding gremlin, noggin, chordin, and follistatin in RNA extracted from the whole gut (Gut) and from separated populations of crest-derived (CD) and noncrest-derived (non-CD) cells. A, Transcripts encoding gremlin and noggin were observed to be present in the whole fetal bowel as early as E12. They were also detected in the brain (Br), which was investigated as a positive control. No PCR products were obtained when reverse transcriptase was omitted (NoRT). B, Transcripts encoding noggin were detected in both the crest-derived and noncrest-derived populations of cells. C, Transcripts encoding chordin and follist at in were detected in the whole fetal bowel as early as E12. Expression of β-actin(A, C) was investigated to semiquantitatively normalize RNA. ad, Adult.