ANXA7 is a member of the annexin family of calcium/phospholipid-binding proteins, and is involved in the process of membrane fusion and exocytosis . Annexin A7 is a GTPase, and both GTPbinding and PKC activity are important in regulating protein function . Membrane binding of annexin A7 is calcium dependent . Two isoforms exist due to alternative splicing. Subcellular localization of annexin A7 has been shown to be in the cytoplasm, vesicular structures, membrane and in adrenal chromaffin granules . Nuclear localization has been shown in the developing mouse central nervous system as well as in adult mouse brain . Annexin A7- deficient mouse studies show that the protein has a role in insulin secretion and calcium signaling as well as cardiac intracellular calcium homeostasis electrical stability . The gene for annexin A7 is a putative tumor suppressor , and alterations in the copy number have been reported in prostate cancer . Annexin A7 expression has alsobeen correlated with survival in human glioblastoma patients , and haploinsufficiency in mice may promote genetic instability leading to tumorigenesis .