Development of gene expression signatures for contact-inhibited and adipogenic-differentiated 3T3-L1 and NIH3T3 fibroblasts. Mus musculus

Given previous works showing that, in the process of adipogenic differentiation of 3T3-L1 fibroblasts, the cells need to be cultured to confluency followed by additional incubation before initiating differentiation, we hypothesized that contact inhibition of proliferation (CIP) is requisite for making the cells prone to the differentiation. We screened upregulated genes in contact-inhibited 3T3-L1 fibroblasts, as well as NIH3T3 fibroblasts that are also sensitive to contact inhibition, by a whole genome microarray analysis. We also screened the genes that undergo rapid downregulation after the initiation of adipogenic differentiation. Overall design: To investigate the mechanism of contact inhibition of proliferation and adipogenic differentiation of 3T3-L1 and NIH3T3 fibroblasts, we have employed whole genome microarray expression profiling as a discovery platform to identify genes with the potential to distinguish proliferating and contact-inhibited cells and cells that undergo adipogenic differentiation. Total RNAs from 80% confluent (3T3-L1_80%, NIH3T3_80%) and overconfluent (3T3-L1_overconfluent, NIH3T3_overconfluent) cells and cells stimulated with the adipogenic differentiation medium (ZenBio) for 2 hours (3T3-L1_adipo diff med 2 hours, NIH3T3_adipo diff med 2 hours) were harvested and subjected to the microarray analysis.