What is the Origin of Prohormone Convertases?

The term is a compound of "prohormone," referring to the inactive precursor molecule, and "convertase," derived from the Latin convertere (to turn around, transform), signifying the enzyme's function of converting one form to another. This biochemical nomenclature highlights the transformative role of these enzymes in the endocrine synthesis pathway.

What is the Mechanism of Prohormone Convertases?

The mechanism of action for prohormone convertases involves recognizing and cleaving specific pairs of basic amino acids, typically Lys-Arg or Arg-Arg, within the prohormone sequence, a process that occurs primarily within the secretory granules of endocrine cells. The cleavage removes the pro-sequence, which often inhibits the hormone's activity, thus liberating the mature, fully functional peptide hormone. This tightly regulated proteolytic processing is a crucial checkpoint for controlling the bioavailability and potency of many essential endocrine messengers.

Prohormone Convertases

Meaning

Prohormone convertases (PCs) are a family of highly specific, calcium-dependent serine endoproteases responsible for the post-translational processing of inactive precursor proteins, known as prohormones or proproteins, into their biologically active forms. These enzymes are essential for the final maturation of numerous critical signaling molecules, including peptide hormones like insulin, glucagon, and pro-opiomelanocortin (POMC)-derived peptides, as well as various neuropeptides and growth factors. The precise cleavage activity of PCs dictates the final functional hormone repertoire available to the body.