Project description:Nucleolus-associated DNA was isolated from MEF cells before and after conditional knock-out of UBF and hybridized against genomic DNA in biological replicates. Two different types of immortalized MEF cells were used. MEFs were immortalized by genetic depletion of p53, iMEFs were immortalized by transfection of the SV40 Tt antigen.
Project description:SV40 large T antigen (TAg) contributes to cell transformation, in part, by targeting two well characterized tumor suppressors, pRb and p53. TAg expression affects the transcriptional circuits controlled by Rb and by p53. We have performed a microarray analysis to examine the global change in gene expression induced by wild-type TAg and TAg-mutants, in an effort to link changes in gene expression to specific transforming functions. For this analysis we have used enterocytes from the mouse small intestine expressing TAg. Expression of TAg in the mouse intestine results in hyperplasia and dysplasia. Our analysis indicates that practically all gene expression regulated by TAg in enterocytes is dependent upon its binding and inactivation of the Rb-family proteins.