Phospholipase A2 activating protein is required for 1α,25-dihydroxyvitamin D3 dependent rapid activation of protein kinase C via Pdia3

► PLAA and Pdia3 are localized to caveolae. ► PLAA interacts with Pdia3 receptor complex in presence of 1α,25(OH)2D3. ► Blocking PLAA with PLAA-antibody suppresses activation of 1α,25(OH)2D3-rapid membrane mediated pathway. ► PLAA silenced MC3T3-E1 cells fail to activate the rapid pathway in response to 1α,25(OH)2D3.