Expression levels of the β-type proteasome subunits in proliferating and senescent WI-38 cells. Cytosolic extracts were prepared from proliferating and senescent WI-38 cells. Samples were analyzed by immunoblot using antibodies specific for each of the β-type proteasome subunits. Actin served as a loading control. Levels of p21WAF1 (p21) were also determined to serve as an inducible marker for replicative senescence. Results from duplicate cultures are shown.
Place et al. BMC Cell Biology 2005 6:37 doi:10.1186/1471-2121-6-37