[Studies of the gene expression and structure alteration of vimentin during differentiation of rat preadipocytes]

Observations on structure and distribution of vimentin as determined by indirect immunofluorescence were showed that the arrangement of vimentin intermediate filments (IFs) changed from an extended fibrillar state to a complex cage formation tightly associated with the forming lipid globules during adipose conversion of rat preadipocytes. The effects of differentiation of rat preadipocytes into adipocytes on vimentin mRNA levels as determined by in situ hybridization (ISH) using oligonucleotides probes to vimentin mRNA labeled by digoxigenin (DIG), and on vimentim protein expression as determined by Western blotting were researched. The results suggested that the expressions of vimentin with molecular weight of about 57 kD at the levels of both mRNA and protein was existed throughout the predipocyte differentiation and downregulation of vimentin is required for adipose conversion. The specificity of the association of lipid globules with vimentin IFs during adipose conversion was taken as an example of a possible IF function in relation to a preadipocytes differentiation process, especially discussed as a functional relationship in supporting adiposgenesis.