Fig. 2.

NR2A and LRP form a complex after tat treatment, and PSD-95 may mediate complex formation. (A) LRP or NR2A antibodies were used for immunoprecipitation (IP) from lysates of control (time 0) cultures or cultures treated with tat or tat plus CCL2 for 5, 10, 15, 30, 45, 60, and 180 min. Samples were analyzed by Western blotting (WB) with the antibody indicated; input samples were used as loading controls. Human cortex lysate (Cortex) was used as a positive control for NR2A and LRP. (B and C) Densitometric analysis of the CoIP protein compared with the amount in the input (n = 5). Tat treatment increased association of NR2A and LRP maximally at 10–45 min (∗, P < 0.05 vs. control). The association was largely blocked by CCL2 (#, P < 0.05 vs. tat alone). (D) PSD-95 was immunoprecipitated from lysates of control cultures (time 0) or cultures treated with tat or tat plus CCL2 and analyzed by WB with antibodies to NR2A and to LRP. (E and F) Quantification of these data (n = 5). Tat treatment increased association of PSD-95 with LRP and with NR2A (∗, P < 0.05 vs. control). These effects were blocked by CCL2 (#, P < 0.05 vs. tat treatment). (G) The total input protein was used as a loading control for each IP (Input and data not shown).