When 3T3 cells undergo adipose differentiation, they are reprogrammed by changes in gene expression of sufficient magnitude to greatly alter the protein composition of the cells. Three participating genes encode glycerophosphate dehydrogenase, a lipid-binding protein, and a serine protease. These three genes have now been cloned and sequenced. Their exon/intron structures are described, together with some interesting peculiarities and some regions of common sequence. It remains to be demonstrated whether the information for common participation of the genes in the program of differentiation resides in controlling elements within the regions sequenced.