Expression of the alpha-fetoprotein gene in pluripotent and committed cells.

We have studied the structure and expression of the alpha-fetoprotein gene in various cell types which differ in their capacity to synthesize alpha-fetoprotein. In all cells and tissues examined the levels of alpha-fetoprotein RNA found in the nucleus and cytoplasm were consistent with the hypothesis that alpha-fetoprotein expression is transcriptionally regulated. The alpha-fetoprotein gene was insensitive to deoxyribonuclease I in both undifferentiated embryonal carcinoma cells and in differentiated tissues which do not express alpha-fetoprotein, whereas in endoderm cells derived from the embryonal carcinoma cells and in alpha-fetoprotein-producing tissues the gene was sensitive to deoxyribonuclease I.