Induction of Differentiation of 3T3-L1 Fibroblasts to Adipocytes by 3-Deazaadenosine and Insulin

摘要

Because of the hypothesis that DNA hypomethylation may lead to gene expression and cellular differentiation, we examined the effect of 3-deazaadenosine on the differentiation of 3T3-L1 fibroblasts to adipocytes (fat cells). This subline of fibroblasts, 3T3-L1, can undergo spontaneous differentiation to become adipocytes upon confluency. In addition to insulin and many other inducing agents, dzAdo has been found to increase the frequency of conversion of the 3T3-L1 fibroblasts to adipocytes. Our data showed that hypomethylation of DNA might not be involved in the differentiation of 3T3-L1 cells to adipocytes, whether dzAdo or insulin was used as an inducer. However, the hypomethylation of specific genes could not be ruled out at present; in this case, our assay methods were not sensitive enough to detect the differences. The induction of differentiation of 3T3-L1 cells by dzAdo, nonetheless, points to an effect on cellular transmethylation. The effect observed with tunicamycin suggests that receptor integrity is required, in addition to a hypomethylation step.