Tyrosine phosphorylation of Pyk2 in primary human macrophages occurs in response to HIV-1 R5 Env.

(A) Week-old cultures of MDMs were unstimulated (CTR) or exposed for 5 minutes to JRFL gp120 (2.5 μg/mL), lysed, and subjected to immunoprecipitation with an anti-Pyk2 antibody. Immune complexes were resolved on 8% SDS-PAGE, transferred to a nitrocellulose membrane, and subjected to serial immunoblotting with an antiphosphotyrosine 4G10 antibody (upper panel) and an anti-Pyk2 antibody (lower panel). (B) MDMs were unstimulated (CTR) or exposed to JRFL gp120 (2.5 μg/mL) for the indicated times (minutes). Cell lysates were resolved by 8% SDS-PAGE, transferred to a nitrocellulose membrane, and probed with anti-Pyk2 phosphospecific [pY402] antibody (upper panel, P-Pyk2). The same blot was then reprobed with an antibody specific for total Pyk2 (lower panel). Blots shown are representative of 5 independent experiments using different donors.