INCREASING VIMENTIN EXPRESSION ASSOCIATED WITH DIFFERENTIATION OF HUMAN AND RAT PREADIPOCYTES

Alterations in the cytoskeletal apparatus constitute some of the earli est changes during assumption of an adipogenic phenotype, We examined three major cytoskeletal elements, beta-actin, alpha-tubulin and vimen tin during adipogenesis in euploid cells from human and rat adipose ti ssue. As reported with 3T3 sub-lines, mRNA levels for beta-actin and a lpha-tubulin were decreased upon differentiation. However, in contrast to reports with 3T3 cells, levels of vimentin were increased during d ifferentiation. Furthermore, immunological analyses confirmed that the re was no decrease in vimentin protein levels during adipogenic develo pment, As well as highlighting a difference between 3T3 cell lines and preadipocytes isolated from fat depots, these studies indicate that t he pattern of cytoskeletal gene expression undergoes complex changes e arly during preadipocyte differentiation.