Recombinant Human SSR4 protein (denatured)

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

SSR4 also known as TRG4 or CDG1S is a subunit of the signal recognition particle receptor responsible for the translocation of proteins across the membrane of the endoplasmic reticulum. With an approximate mass of 24 kDa SSR4 is expressed predominately in tissues with high secretory functions such as the liver and pancreas. It plays an important role in facilitating the proper insertion and folding of nascent polypeptide chains by cooperating with other components of the translocation machinery.

Biological function summary

SSR4 functions as part of the signal sequence receptor (SSR) complex. This complex is essential for the targeting and translocation of newly synthesized proteins into the endoplasmic reticulum lumen. SSR4 interacts directly with signal sequences of nascent polypeptides to ensure their correct orientation and localization during protein synthesis. Proper functioning of SSR4 is necessary for the homeostasis of the cellular secretory pathway.

Pathways

SSR4 is involved in the protein translocation pathway which is essential for protein sorting and trafficking. This pathway intersects with the unfolded protein response (UPR) pathway which maintains protein homeostasis under stress conditions. In these pathways SSR4 collaborates with proteins like Sec61 to mediate translocation and assist in protein folding. Disruptions in these pathways can lead to cellular dysfunction and stress-related responses.

Defects or alterations in SSR4 are linked to congenital disorders of glycosylation (CDGs) which affect multiple organ systems. Altered glycoprotein production in these disorders results from impaired protein translocation demonstrating SSR4’s influence on glycoprotein processing. Furthermore SSR4 may interact with proteins like glycosyltransferases affecting their function in cellular processes and contributing to the broad clinical spectrum observed in CDGs.