S100A10Annexin

S100A10, also known as annexin A2 p10, is a protein that in humans is encoded by the S100A10 gene. It belongs to the annexin family, a group of calcium-binding proteins that play roles in membrane-related events, including exocytosis, endocytosis, and intracellular signaling. S100A10 is closely associated with annexin A2 (S100A2), forming a heterotetrameric complex that functions in various cellular processes.

The S100A10 gene is located on chromosome 1q21.3 and consists of four exons. The protein itself is approximately 11 kDa in size and contains a lipid-binding domain that facilitates its interaction with phospholipids in cell membranes. This interaction is calcium-dependent, allowing S100A10 to modulate membrane dynamics and vesicle trafficking.

S100A10 is widely expressed in various tissues, including the brain, heart, liver, and skeletal muscle, with particularly high levels found in endothelial cells and platelets. Its functions extend beyond membrane stabilization, as it also participates in cell migration, proliferation, and inflammation. The protein has been implicated in processes such as angiogenesis, wound healing, and immune responses.

In pathological contexts, S100A10 has been linked to several diseases. Elevated levels have been observed in conditions like atherosclerosis, cancer (including breast and colorectal cancers), and neurodegenerative disorders. Its role in cancer progression suggests potential as a biomarker or therapeutic target, though further research is needed to clarify its exact mechanisms.

Structurally, S100A10 shares similarities with other annexins, featuring a conserved core domain that binds calcium and phospholipids. Unlike some annexins, it lacks a transmembrane domain, relying instead on peripheral membrane association. The protein’s ability to form heterodimers with annexin A2 enhances its functional versatility, contributing to its diverse roles in cellular physiology.