QPCT
Description
The QPCT (glutaminyl-peptide cyclotransferase) is a protein-coding gene located on chromosome 2.
The QPCT gene encodes human pituitary glutaminyl cyclase, an enzyme responsible for the presence of pyroglutamyl residues in many neuroendocrine peptides. The amino acid sequence of this enzyme is 86% identical to that of bovine glutaminyl cyclase.
QPCT is responsible for the biosynthesis of pyroglutamyl peptides. It has a preference for non-acidic and non-tryptophan residues next to the N-terminal glutaminyl residue, and the length of the chain after the second residue is not significant. It also catalyzes N-terminal pyroglutamate formation. In vitro, QPCT catalyzes pyroglutamate formation of N-terminally truncated forms of APP amyloid-beta peptides, specifically [Glu-3]-amyloid-beta. QPCT might be involved in the N-terminal pyroglutamate formation of various amyloid-related plaque-forming peptides.
QPCT is also known as GCT, QC, sQC.
Associated Diseases
- Alzheimer disease
- multiple sclerosis
- lysosomal storage disease
- Parkinson disease
- schizophrenia
- esophageal ulcer
