preproinsuliinista

Preproinsulin is a precursor protein that plays a crucial role in the regulation of blood glucose levels. It is synthesized in the beta cells of the pancreas and is a single-chain polypeptide consisting of 110 amino acids. Preproinsulin is processed into insulin and other biologically active peptides, including C-peptide, which is released along with insulin into the bloodstream. The processing of preproinsulin involves the removal of a signal peptide and the conversion of the remaining polypeptide into insulin and C-peptide by specific proteases. Insulin, derived from preproinsulin, is a hormone that facilitates the uptake of glucose by cells, thereby lowering blood glucose levels. Preproinsulin is also a marker for pancreatic beta-cell function and is used in diagnostic tests to assess insulin secretion. Its structure and processing are well-characterized, making it a valuable model for studying protein processing and hormone secretion.