Protein shisa-5 (SHISA5)

Protein shisa-5 (SHISA5, also known as SCOTIN) is a single-pass transmembrane adaptor protein residing in the endoplasmic reticulum membrane[1][3]. It functions mainly as a suppressor of basal autophagy, preventing spontaneous formation of autophagic structures by blocking contact between the phagophore and ER exit sites under normal nutrition conditions[1]. SHISA5 is also involved in cell death pathways, notably acting with p53 to induce apoptosis via a caspase-dependent mechanism[3]. The protein is upregulated in certain disease contexts, including liver disorders such as primary biliary cholangitis, where it correlates with disease activity[2]. In cancer and viral infection models, SHISA5 has been implicated in tumor suppression and viral protein degradation, respectively[4]. No drugs are currently known to specifically target SHISA5, nor are drug-specific safety issues documented.

Other names

SHISA5SCOTINPSEC0133hShisa5Putative NF-kappa-B-activating protein 120Scotinshisa homolog 5protein shisa-5

Not established for drug intervention. In a biological context, suppresses basal autophagy via blockade at the ER exit site and can induce apoptosis in a caspase- and p53-dependent way[1][3].