Chromogranin A

Chromogranin A or parathyroid secretory protein 1 (gene name CHGA) is a member of the granin family of neuroendocrine secretory proteins, i.e., it is located in secretory vesicles of neurons and endocrine cells such as islet beta cell secretory granules in pancreas. In humans, chromogranin A protein is encoded by the CHGA gene.

Tissue distribution

Examples of cells producing chromogranin A (ChgA) are chromaffin cells of the adrenal medulla, paraganglia, enterochromaffin-like cells and beta cells of the pancreas. It is present in islet beta cell secretory granules.

Function

Chromogranin A is the precursor to several functional peptides including vasostatin-1, vasostatin-2, pancreastatin, catestatin and parastatin. These peptides negatively modulate the neuroendocrine function of the releasing cell (autocrine) or nearby cells (paracrine).

Chromogranin A induces and promotes the generation of secretory granules such as those containing insulin in pancreatic islet beta cells.