QSOX1

This gene encodes a protein that contains domains of thioredoxin and ERV1, members of two long-standing gene families. The gene expression is induced as fibroblasts begin to exit the proliferative cycle and enter quiescence, suggesting that this gene plays an important role in growth regulation. Two transcript variants encoding two different isoforms have been found for this gene.

Full Name

quiescin Q6 sulfhydryl oxidase 1

Function

Catalyzes the oxidation of sulfhydryl groups in peptide and protein thiols to disulfides with the reduction of oxygen to hydrogen peroxide (PubMed:17331072, PubMed:18393449, PubMed:23704371, PubMed:30367560, PubMed:23867277).
Plays a role in disulfide bond formation in a variety of extracellular proteins (PubMed:17331072, PubMed:30367560, PubMed:22801504, PubMed:23867277).
In fibroblasts, required for normal incorporation of laminin into the extracellular matrix, and thereby for normal cell-cell adhesion and cell migration (PubMed:23704371, PubMed:30367560, PubMed:23867277).

Biological Process

Biological Process extracellular matrix assemblyManual Assertion Based On ExperimentIMP:UniProtKB
Biological Process negative regulation of macroautophagyManual Assertion Based On ExperimentIMP:CACAO
Biological Process protein foldingManual Assertion Based On ExperimentIBA:GO_Central

Cellular Location

Isoform 1
Golgi apparatus membrane
Secreted
A small proportion is secreted, probably via a proteolytic cleavage that removes the membrane anchor.
Isoform 2
Secreted
Found in the extracellular medium of quiescent cells but is not found in proliferating cells.

Topology

Helical: 710-730

PTM

N-glycosylated (PubMed:17331072, PubMed:29757379).
O-glycosylated on Thr and Ser residues (PubMed:29757379).