Stress-associated endoplasmic reticulum protein 1 (SERP1)

Stress-associated endoplasmic reticulum protein 1 (SERP1), also called RAMP4, is an evolutionarily conserved membrane protein of the ER that is upregulated during ER stress and interacts directly with the Sec61 translocon complex[1][2][4]. It stabilizes nascent, unfolded, or misfolded membrane proteins during conditions of cellular stress, preventing their degradation in the ER[1][3][4]. SERP1 regulates aspects of protein translocation and glycosylation, including ensuring the correct processing of secretory and membrane proteins and the glycosylation of MHC class II-associated invariant chains[1][2][4]. Loss of SERP1 function leads to increased ER stress, defective insulin production, and impaired growth hormone response[4]. Clinically, altered expression is associated with cancer prognosis and certain metabolic or endocrine disorders[1][3][4]. SERP1 serves no known receptor, enzyme, or transporter function but is a critical ER scaffolding and quality control protein.

Other names

Ribosome-associated membrane protein 4 (RAMP4)Ysy6 (yeast homolog)FLJ43424Ribosome-attached membrane protein 4