Clusterin-like (IPR000753)

Short name: Clusterin-like

Overlapping homologous superfamilies


Family relationships

  • Clusterin-like (IPR000753)


Clusterin (Clu), also known as apolipoprotein J, is a vertebrate glycoprotein [PMID: 1585460]. Clusterin expression is complex, appearing as different forms in different cell compartments. One set of proteins is directed for secretion, and other clusterin species are expressed in the cytoplasm and nucleus. The secretory form of the clusterin protein (sCLU) is targeted to the ER by an initial leader peptide. This ~60kDa pre-sCLU protein is proteolytically cleaved into alpha- and beta-subunits and further glycosylated to form mature disulfide-linked heterodimeric secretory CLU (sCLU). sCLU is an 80kDa protein and acts as a molecular chaperone, scavenging denatured proteins outside cells [PMID: 21505792, PMID: 19535339]. sCLU possesses nonspecific binding activity to hydrophobic domains of various non-native proteins [PMID: 12551933], binds to some bacteria and bacterial proteins [PMID: 11720815], and interacts with different immune molecules [PMID: 27148688].

A specific nuclear form of CLU (nCLU) acts as a pro-death signal, inhibiting cell growth and survival. The nCLU protein has two coiled-coil domains, one at its N terminus that is unable to bind Ku70, and a C-terminal coiled-coil domain that is uniquely able to associate with Ku70 and is minimally required for cell death. The sCLU protein is cytoprotective and anti-apoptotic, whereas the nCLU protein is pro-apoptotic [PMID: 21953454, PMID: 22588555, PMID: 22025968].

This family also includes clusterin-like protein 1 (CLUL1), which is expressed specifically in cone photoreceptor cells [PMID: 10675623] and is likely to be necessary for normal cone function [PMID: 14507903].

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.