Canopy FGF signaling regulator 2 (CNPY2)

Canopy FGF signaling regulator 2 (CNPY2) is an endoplasmic reticulum-localized protein belonging to the saposin-like protein family, characterized by a conserved pattern of cysteine residues and an ER retention signal[1][3][5]. It is multifunctional, acting as a regulator of the unfolded protein response (UPR) by engaging the PERK-CHOP branch during ER stress: CNPY2 is released from GRP78, binds PERK, and initiates pro-survival or pro-death signaling pathways, depending on cell context[3]. CNPY2 also stabilizes target proteins (such as myosin regulatory light chain and LDL receptor) by inhibiting their ubiquitination, thereby influencing cell signaling, lipid/cholesterol homeostasis, and protein turnover[5]. In the nervous system, CNPY2 promotes neurite outgrowth and neuronal survival by mitigating ER stress[1][2]. In cancer, CNPY2 enhances tumor cell proliferation by interfering with ubiquitin-mediated degradation of several key proteins[4]. It is also a hypoxia-inducible, partially secreted protein that regulates angiogenesis and smooth muscle cell migration through activation of pathways such as Cdc42, PAK1, and FAK[6]. Upregulation or dysregulation of CNPY2 is implicated in diseases including metabolic syndrome, hepatic steatosis, neurodegenerative disease, and cancer, making it a potential therapeutic target for these conditions[1][3][4][6]. Notes: - There are no established interacting drugs or standardized mechanisms of action for drug targeting as of current literature. - CNPY2 is not a classical receptor, transporter, or enzyme but plays a key role in various cell signaling pathways and ER stress regulation. - No validated clinical biomarkers or defined safety concerns for therapeutic targeting have been described to date.

Other names

Protein canopy homolog 2MSAPTMEM4ZSIG9UNQ1943/PRO4426HP10390MIR-interacting saposin-like proteinPutative secreted protein Zsig9Transmembrane protein 4