Reticulocalbin-1 (RCN1)

Reticulocalbin-1 (RCN1) is an endoplasmic reticulum-resident calcium-binding protein from the CREC family, distinguished by six EF-hand domains and an HDEL ER retention signal. RCN1 regulates intracellular calcium homeostasis, modulates the unfolded protein response during ER stress, and inhibits stress-induced apoptosis through direct interaction with the inositol 1,4,5-trisphosphate receptor 1 (IP3R1). It also operates as a microglial phagocytosis ligand, facilitating the clearance of apoptotic cells, and is linked to cell proliferation and tumor progression, notably in oral, breast, and colorectal cancers. RCN1 expression in the plasma membrane is increased under certain stimuli, such as tumor necrosis factor alpha, and aberrant RCN1 expression or deletion affects development and disease, making it a possible biomarker and therapeutic target.

Other names

Reticulocalbin-1RCN1RCNRcalPIG20FLJ37041Proliferation-inducing gene 20HEL-S-84RCALEpididymis secretory protein Li 84

Suppression of ER stress-induced apoptosis via inhibition of ER calcium release and regulation of UPR signaling, specifically PERK- and IRE1-mediated pathways. Facilitates microglial phagocytosis by serving as a ligand for apoptotic cells.