背景
This gene encodes a transcription factor that activates target genes for the unfolded protein
response (UPR) during endoplasmic reticulum (ER) stress. Although it is a transcription
factor, this protein is unusual in that it is synthesized as a transmembrane protein that is
embedded in the ER. It functions as an ER stress sensor/transducer, and following ER stressinduced proteolysis, it functions as a nuclear transcription factor via a cis-acting ER stress
response element (ERSE) that is present in the promoters of genes encoding ER chaperones.
This protein has been identified as a survival factor for quiescent but not proliferative
squamous carcinoma cells. There have been conflicting reports about the association of
polymorphisms in this gene with diabetes in different populations, but another
polymorphism has been associated with increased plasma cholesterol levels. This gene is
also thought to be a potential therapeutic target for cystic fibrosis.
