Figure 2. Effect of cell density and serum on the nuclear localization of LPA₁.

PC12 cells, CHO cells and cerebellar granule neurons were grown to either low or high density and immunostained with anti-LPA₁^328–344 antibody and detected with anti-(rabbit FITC-conjugated) secondary antibody to show the effect of cell density on the nuclear localization of LPA₁ in: (A) serum-deprived PC12 cells; (B) serum-deprived CHO cells, and; (C) cerebellar granule neurones. DAPI staining was used as a nuclear marker. (D) Low-speed nuclear pellets (N) and high-speed membrane pellets (M) from serum-deprived PC12 cells grown to low and high density were subjected to Western blotting probed with anti-LPA₁^328–344 antibody. (E) Histogram showing the effect of serum and delipidation of serum on the number of PC12 cells containing LPA₁ in the nucleus. Cells were maintained in serum or delipidated serum or serum-free conditions for 24 h. Results are means±S.D. for three separate experiments (*P<0.05 for quiescent versus serum).