Calcium-regulated membrane-binding protein whose affinity for calcium is greatly enhanced by anionic phospholipids. It binds two calcium ions with high affinity. May be involved in heat-stress response. Inhibits PCSK9-enhanced LDLR degradation, probably reduces PCSK9 protein levels via a translational mechanism but also competes with LDLR for binding with PCSK9. Heterotetramer containing 2 light chains of S100A10/p11 and 2 heavy chains of ANXA2/p36 (By similarity). Interacts with ATP1B1 (By similarity). Interacts with DYSF (By similarity). Interacts with COCH. Interacts (via repeat Annexin 1) with PCSK9 (via the C-terminal domain); the interaction inhibits the degradation of LDLR. Interacts with CEACAM1 (via the cytoplasmic domain); this interaction is regulated by phosphorylation of CEACAM1 (By similarity). Interacts with APPL2 and APPL1; targets APPL2 to endosomes and acting in parallel to RAB5A (By similarity). Interacts with S100A4 (By similarity). In the lamina beneath the plasma membrane. Expressed strongly in velvet antler reserve mesenchyme. A pair of annexin repeats may form one binding site for calcium and phospholipid. ISGylated. It may cross-link plasma membrane phospholipids with actin and the cytoskeleton and be involved with exocytosis. Belongs to the annexin family. Red velvet - Issue 86 of September 2007