trypsynogenu

Trypsynogenu is a term used in some languages to refer to the pancreatic enzyme precursor known in English as trypsinogen. Trypsinogen is the inactive zymogen form of the serine protease trypsin, produced mainly by pancreatic acinar cells and secreted into the small intestine as part of pancreatic juice. The zymogen form prevents premature proteolysis of pancreatic tissue.

In humans, there are three major trypsinogen genes: PRSS1 (cationic trypsinogen), PRSS2 (anionic trypsinogen), and PRSS3 (mesotrypsinogen). These genes encode proenzymes that share a common structure, including a signal peptide, an activation peptide, and the catalytic domain. Activation occurs in the duodenum when the activation peptide is removed by enteropeptidase (enterokinase), generating active trypsin. Active trypsin then initiates the digestion of proteins and also activates other pancreatic zymogens such as chymotrypsinogen and procarboxypeptidase, amplifying digestive enzyme activity.

Function and regulation: Trypsin cleaves peptide bonds on the carboxyl side of lysine and arginine residues, contributing to protein digestion in the small intestine. Its activity is tightly regulated by protease inhibitors, notably SPINK1, which protects pancreatic tissue from premature activation of trypsin.

Clinical relevance: Mutations in PRSS1 or SPINK1 can predispose individuals to pancreatitis, often by altering trypsinogen activation or inhibition. Measuring trypsinogen or its active forms can be relevant in diagnostic contexts, such as newborn screening for cystic fibrosis (immunoreactive trypsinogen) or assessment of pancreatic exocrine function.

See also: pancreas, digestive enzymes, enteropeptidase, zymogen.