DECREASING EXPRESSION OF A GENE ENCODING A PROTEIN RELATED TO BASIC FIBROBLAST GROWTH-FACTOR DURING DIFFERENTIATION OF HUMAN PREADIPOCYTES

Pursuant to our findings that pituitary basic fibroblast growth factor (bFGF) stimulates the replication of preadipocytes and inhibits their differentiation, we have studied the changes in expression of a bFGF-related mRNA during differentiation. Human omental preadipocytes were grown in primary culture and induced to differentiate with chemically defined serum-free medium. The differentiation process was assessed by monitoring the rise of glycerophosphate dehydrogenase (GPDH) activity, while mRNA expression for a bFGF-related protein(s) and GPDH was examined by amplifying the respective target sequences by polymerase chain reaction. In the case of all cell strains, differentiated preadipocytes revealed much lower expression of bFGF-related mRNA than undifferentiated preadipocytes. Concurrently, the expression of the GPDH mRNA rose significantly. The finding that the expression of the bFGF-related protein is decreased appreciably during adipose differentiation is consonant with its proposed function to expand and maintain adipose cells in a relatively undifferentiated state.