Chromogranin A in the early steps of the neurosecretory pathway
Abstract
Chromogranin A (CgA) is a soluble glycoprotein stored with hormones and
neuropeptides in secretory granules (SG) of most (neuro)endocrine cells and
neurons. Since its discovery in 1967, many studies have reported its structural
characteristics, biological roles, and mechanisms of action. Indeed, CgA is both
a precursor of various biologically active peptides and a granulogenic protein
regulating the storage and secretion of hormones and neuropeptides. This
review emphasizes the findings and theoretical concepts around the CgAlinked
molecular machinery controlling hormone/neuropeptide aggregation
and the interaction of CgA-hormone/neuropeptide aggregates with the trans-
Golgi membrane to allow hormone/neuropeptide targeting and SG biogenesis.
We will also discuss the intriguing alteration of CgA expression and secretion
in various neurological disorders, which could provide insights to elucidate the
molecular mechanisms underlying these pathophysiological conditions.