Figure 5.
SDF-1μ regulates Rb expression and phosphorylation in HOS-CXCR4 cells. (A) Immunostaining for Rb in control cells (left panel) and SDF-treated cells (SDF-1μ 20 nM, 3-h treatment in regular medium) showing higher levels of Rb (green) in treated cells. (B) The same antibody was used for immunoblots (SDF-1μ 20 nM): total cell lysates (top) or cytosolic and nuclear extracts (20 μg protein/lane). Treatment with CHX prevents the effect of SDF-1μ on Rb (bottom). (C) The left panel shows immunoblots for pRb (Ser795) with the same total cell lysates used in B. In vitro kinase assay showing a reduction in GST-Rb phosphorylation following SDF-1μ (20 nM) treatment.