Differential proteome analysis of replicative senescence in rat embryo fibroblasts.

Normal somatic cells undergo a finite number of divisions and then cease dividing whereas cancer cells are able to proliferate indefinitely. To identify the underlying mechanisms that limit the mitotic potential, a two-dimensional differential proteome analysis of replicative senescence in serially passaged rat embryo fibroblasts was undertaken. Triplicate independent two-dimensional gels containing over 1200 spots each were run, curated, and analyzed.

Identification of novel candidates for replicative senescence by functional proteomics.

To identify the underlying mechanisms that limit the mitotic potential of normal somatic cells, we have undertaken a high resolution differential proteomic analysis aimed at identifying proteins that were differentially expressed upon replicative senescence. Since replicative senescence in heterogeneous primary fibroblast cultures is asynchronous, we analysed a group of conditionally immortalized rat embryo fibroblast cell lines that have previously been shown to undergo synchronous senescence upon inactivation of SV40 tsA58 T antigen. This identified 43 spots that were differentially expressed in these cell lines.