Tag Content
UniProt Accession
Theoretical PI
Molecular Weight
51656 Da  
Genbank Nucleotide ID
Genbank Protein ID
Gene Name
Gene Synonyms/Alias
Apoj, Msgp-2 
Protein Name
Clusterin Clusterin beta chain Clusterin alpha chain 
Protein Synonyms/Alias
Apolipoprotein J;Apo-J Clustrin; Sulfated glycoprotein 2;SGP-2Contains:Contains:Flags: Precursor 
Mus musculus (Mouse) 
NCBI Taxonomy ID
Chromosome Location
View in Ensembl genome browser  
Function in Stage
Function in Cell Type
Probability (GAS) of Function in Spermatogenesis
The probability was calculated by GAS algorithm, ranging from 0 to 1. The closer it is to 1, the more possibly it functions in spermatogenesis.
Temporarily unavailable 
Abstract of related literatures
1. We cloned a mouse homolog of sulfated glycoprotein-2 (SGP-2) cDNA by screening a mouse testicular cDNA library and its nucleotide sequence was determined. The predicted amino acid sequence of the cDNA shares 93% identity with that of rat SGP-2. The nucleotide sequences of both cDNAs show extensive homology throughout the open reading frames and 3' untranslated regions. The 5' untranslated regions, however, share homology only up to 28 bp upstream from the start codons; the rest of sequences are quite different. DNA sequence homology search to mouse SGP-2 cDNA through the EMBL/GenBank database and a recent study on the genomic organization of rat TRPM-2 gene suggest a possibility that there are at least two different SGP-2 mRNAs as a result of alternative splicing and/or different promoter usage in mouse. PMID: [8352774] 

2. Clusterin is a broadly distributed glycoprotein constitutively expressed by various tissues and cell types, that has been shown to be involved in cell-cell adhesion and expressed during cellular differentiation in vitro. To assess the suggested participation of clusterin in these processes in vivo, we have cloned the cDNA encoding murine clusterin and studied the cellular distribution of clusterin mRNA during murine embryogenesis. Sequence analysis of the cDNA encoding murine clusterin revealed 92 and 75% sequence identity with the rat and human cDNAs, respectively, and conservation of the predicted structural features which include alpha-helical regions and heparin-binding domains. From 12.5 d of development onwards, the clusterin gene is widely expressed in developing epithelia, and selectively localized within the differentiating cell layers of tissues such as the developing skin, tooth, and duodenum where proliferating and differentiating compartments are readily distinguished. In addition, transient and localized clusterin gene expression was detected in certain morphogenetically active epithelia. In the lung, abundant gene transcripts were detected in cuboidal epithelial cells of the terminal lung buds during branching morphogenesis, and in the kidney, clusterin gene expression in the epithelial cells of comma and S-shaped bodies coincided with the process of polarization. Our results demonstrate the in vivo expression of the clusterin gene by differentiating epithelial cells during murine embryogenesis, and provide novel evidence suggesting that clusterin may be involved in the differentiation and morphogenesis of certain epithelia. PMID: [8354695] 

3. Apolipoprotein J (apoJ), a glycoprotein associated with subclasses of plasma high density lipoproteins (HDL), was found to accumulate in aortic lesions in a human subject with transplantation-associated arteriosclerosis and in mice fed a high-fat atherogenic diet. Foam cells present in mouse aortic valve lesions expressed apoJ mRNA, suggesting local synthesis contributes to apoJ's localization in atherosclerotic plaque. As a prerequisite for elucidating the physiological function of apoJ by using a mouse model, cDNA clones representing the mouse homolog of apoJ were isolated, characterized, and sequenced. The nucleotide sequence predicts a 448 amino acid, 50,260 dalton protein. There was 81% nucleotide sequence similarity between mouse and human apoJ, and 75% similarity at the amino acid level. Mouse apoJ contains six potential N-glycosylation sites, a potential Arg-Ser cleavage site to generate alpha and beta subunits, a cluster of five cysteine residues in each subunit, three putative amphipathic helices, and four potential heparin-binding domains. Southern blot analysis indicates that the gene encompasses approximately 23 kb of DNA. Recombinant inbred strains were used to map apoJ to mouse chromosome 14, tightly linked to Mtv-11. All of the transcribed portions of the gene were cloned and analyzed, and all intron-exon boundaries were defined. The first of the 9 exons is untranslated. Single exons encode the signal peptide, the cysteine-rich domain in the alpha subunit, two potential amphipathic helices flanking a heparin-binding consensus sequence, and a potential amphipathic helix overlapping a heparin-binding domain, supporting their potential functional significance in apoJ. A variety of mouse tissues constitutively express a 1.9 kb apoJ mRNA, with apparently identical transcriptional start sites utilized in all tissues tested. ApoJ mRNA was most abundant in stomach, liver, brain, and testis, with intermediate levels in heart, ovary, and kidney. The high degree of similarity between mouse and human apoJ, in structure and distribution of the gene product, gene structure, and deposition in atherosclerotic plaques, suggests that the mouse is an ideal model with which to elucidate the role of apoJ in HDL metabolism and atherogenesis. PMID: [8169523] 

4. The National Institutes of Health's Mammalian Gene Collection (MGC) project was designed to generate and sequence a publicly accessible cDNA resource containing a complete open reading frame (ORF) for every human and mouse gene. The project initially used a random strategy to select clones from a large number of cDNA libraries from diverse tissues. Candidate clones were chosen based on 5'-EST sequences, and then fully sequenced to high accuracy and analyzed by algorithms developed for this project. Currently, more than 11,000 human and 10,000 mouse genes are represented in MGC by at least one clone with a full ORF. The random selection approach is now reaching a saturation point, and a transition to protocols targeted at the missing transcripts is now required to complete the mouse and human collections. Comparison of the sequence of the MGC clones to reference genome sequences reveals that most cDNA clones are of very high sequence quality, although it is likely that some cDNAs may carry missense variants as a consequence of experimental artifact, such as PCR, cloning, or reverse transcriptase errors. Recently, a rat cDNA component was added to the project, and ongoing frog (Xenopus) and zebrafish (Danio) cDNA projects were expanded to take advantage of the high-throughput MGC pipeline. PMID: [15489334] 

5. Apolipoprotein J/clusterin (apoJ/clusterin), an intriguing protein with unknown function, is induced in myocarditis and numerous other inflammatory injuries. To test its ability to modify myosin-induced autoimmune myocarditis, we generated apoJ-deficient mice. ApoJ-deficient and wild-type mice exhibited similar initial onset of myocarditis, as evidenced by the induction of two early markers of the T cell-mediated immune response, MHC-II and TNF receptor p55. Furthermore, autoantibodies against the primary antigen cardiac myosin were induced to the same extent. Although the same proportion of challenged animals exhibited some degree of inflammatory infiltrate, inflammation was more severe in apoJ-deficient animals. Inflammatory lesions were more diffuse and extensive in apoJ-deficient mice, particularly in females. In marked contrast to wild-type animals, the development of a strong generalized secondary response against cardiac antigens in apoJ-deficient mice was predictive of severe myocarditis. Wild-type mice with a strong Ab response to secondary antigens appeared to be protected from severe inflammation. After resolution of inflammation, apoJ-deficient, but not wild-type, mice exhibited cardiac function impairment and severe myocardial scarring. These results suggest that apoJ limits progression of autoimmune myocarditis and protects the heart from postinflammatory tissue destruction. PMID: [11067863] 

6. Nuclear clusterin (nCLU) is an ionizing radiation (IR)-inducible protein that binds Ku70, and triggers apoptosis when overexpressed in MCF-7 cells. We demonstrate that endogenous nCLU synthesis is a product of alternative splicing. Reverse transcriptase-PCR analyses revealed that exon II, containing the first AUG and encoding the endoplasmic reticulum-targeting peptide, was omitted. Exons I and III are spliced together placing a downstream AUG in exon III as the first available translation start site. This shorter mRNA produces the 49-kDa precursor nCLU protein. Ku70 binding activity was localized to the C-terminal coiled-coil domain of nCLU. Leucine residues 357, 358, and 361 of nCLU were necessary for Ku70-nCLU interaction. The N- and C-terminal coiled-coil domains of nCLU interacted with each other, suggesting that the protein could dimerize or fold. Mutation analyses indicate that the C-terminal NLS was functional in nCLU with the same contribution from N-terminal NLS. The C-terminal coiled-coil domain of nCLU was the minimal region required for Ku binding and apoptosis. MCF-7 cells show nuclear as well as cytoplasmic expression of GFP-nCLU in apoptotic cells. Cytosolic aggregation of GFP-nCLU was found in viable cells. These results indicate that an inactive precursor of nCLU exists in the cytoplasm of non-irradiated MCF-7 cells, translocates into the nucleus following IR, and induces apoptosis. PMID: [12551933] 

7. A procedure to map N-glycosylation sites is presented here. It can be applied to purified proteins as well as to highly complex mixtures. The method exploits deglycosylation by PNGase F in a diagonal, reverse-phase chromatographic setup. When applied to 10 microL of mouse serum, affinity-depleted for its three most abundant components, 117 known or predicted sites were mapped in addition to 10 novel sites. Several sites were detected on soluble membrane or receptor components. Our method furthermore senses the nature of glycan structures and can detect differential glycosylation on a given site. These properties--high sensitivity and dependence on glycan imprinting--can be exploited for glycan-biomarker analysis. PMID: [16944957] 

8. A comprehensive understanding of the mouse plasma proteome is important for studies using mouse models to identify protein markers of human disease. To enhance our analysis of the mouse plasma proteome, we have developed a method for isolating low-abundance proteins using a cysteine-containing glycopeptide strategy. This method involves two orthogonal affinity capture steps. First, glycoproteins are coupled to an azlactone copolymer gel using hydrazide chemistry and cysteine residues are then biotinylated. After trypsinization and extensive washing, tethered N-glycosylated tryptic peptides are released from the gel using PNGase F. Biotinylated cysteinyl-containing glycopeptides are then affinity selected using a monomeric avidin gel and analyzed by LC-MS/MS. We have applied the method to a proteome analysis of mouse plasma. In two independent analyses using 200 muL each of C57BL mouse plasma, 51 proteins were detected. Only 42 proteins were seen when the same plasma sample was analyzed by glycopeptides only. A total of 104 N-glycosylation sites were identified. Of these, 17 sites have hitherto not been annotated in the Swiss-Prot database whereas 48 were considered probable, potential, or by similarity - i.e., based on little or no experimental evidence. We show that analysis by cysteine-containing glycopeptides allows detection of low-abundance proteins such as the epidermal growth factor receptor, the Vitamin K-dependent protein Z, the hepatocyte growth factor activator, and the lymphatic endothelium-specific hyaluronan receptor as these proteins were not detected in the glycopeptide control analysis. PMID: [17330941] 

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Functions as extracellular chaperone that preventsaggregation of nonnative proteins. Prevents stress-inducedaggregation of blood plasma proteins. Inhibits formation ofamyloid fibrils by APP, APOC2, B2M, CALCA, CSN3, SNCA andaggregation-prone LYZ variants (in vitro). Does not require ATP.Maintains partially unfolded proteins in a state appropriate forsubsequent refolding by other chaperones, such as HSPA8/HSC70.Does not refold proteins by itself. Binding to cell surfacereceptors triggers internalization of the chaperone-client complexand subsequent lysosomal or proteasomal degradation. Whensecreted, protects cells against apoptosis and against cytolysisby complement. Intracellular forms interact with ubiquitin and SCF(SKP1-CUL1-F-box protein) E3 ubiquitin-protein ligase complexesand promote the ubiquitination and subsequent proteasomaldegradation of target proteins. Promotes proteasomal degradationof COMMD1 and IKBKB. Modulates NF-kappa-B transcriptionalactivity. Promotes apoptosis when in the nucleus. Inhibitsapoptosis when associated with the mitochondrial membrane byinterference with BAX-dependent release of cytochrome c into thecytoplasm. Plays a role in the regulation of cell proliferation(By similarity). 
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Subcellular Location
Secreted. Nucleus. Cytoplasm. Mitochondrionmembrane; Peripheral membrane protein; Cytoplasmic side (Bysimilarity). Cytoplasm, cytosol. Microsome (By similarity).Endoplasmic reticulum (By similarity). Cytoplasmic vesicle,secretory vesicle, chromaffin granule (By similarity). Note=Canretrotranslocate from the secretory compartments to the cytosolupon cellular stress. Detected in perinuclear foci that may beaggresomes containing misfolded, ubiquitinated proteins. Detectedat the mitochondrion membrane upon induction of apoptosis (Bysimilarity). 
Tissue Specificity
Most abundant in stomach, liver, brain, andtestis, with intermediate levels in heart, ovary and kidney. 
Gene Ontology
GO IDGO termEvidence
GO:0016235 C:aggresome IEA:Compara.
GO:0042583 C:chromaffin granule IEA:UniProtKB-SubCell.
GO:0005829 C:cytosol IEA:UniProtKB-SubCell.
GO:0005783 C:endoplasmic reticulum IEA:UniProtKB-SubCell.
GO:0030426 C:growth cone IEA:Compara.
GO:0031966 C:mitochondrial membrane IEA:UniProtKB-SubCell.
GO:0005634 C:nucleus IEA:UniProtKB-SubCell.
GO:0048471 C:perinuclear region of cytoplasm ISS:UniProtKB.
GO:0034366 C:spherical high-density lipoprotein particle ISS:UniProtKB.
GO:0006916 P:anti-apoptosis IEA:Compara.
GO:0008219 P:cell death IEA:InterPro.
GO:0071363 P:cellular response to growth factor stimulus IEA:Compara.
GO:0061077 P:chaperone-mediated protein folding ISS:UniProtKB.
GO:0031018 P:endocrine pancreas development IEA:Compara.
GO:0008629 P:induction of apoptosis by intracellular signals ISS:UniProtKB.
GO:0043066 P:negative regulation of apoptotic process ISS:UniProtKB.
GO:0032463 P:negative regulation of protein homooligomerization ISS:UniProtKB.
GO:0048812 P:neuron projection morphogenesis IEA:Compara.
GO:0045597 P:positive regulation of cell differentiation IEA:Compara.
GO:0008284 P:positive regulation of cell proliferation IEA:Compara.
GO:2001244 P:positive regulation of intrinsic apoptotic signaling pathway ISS:UniProtKB.
GO:0051092 P:positive regulation of NF-kappaB transcription factor activity ISS:UniProtKB.
GO:0032436 P:positive regulation of proteasomal ubiquitin-dependent protein catabolic process ISS:UniProtKB.
GO:2000060 P:positive regulation of protein ubiquitination involved in ubiquitin-dependent protein catabolic process ISS:UniProtKB.
GO:0050821 P:protein stabilization ISS:UniProtKB.
GO:0051788 P:response to misfolded protein ISS:UniProtKB.
GO:0006979 P:response to oxidative stress IEA:Compara.
GO:0009611 P:response to wounding IEA:Compara.
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IPR016016;    Clusterin.
IPR000753;    Clusterin-like.
IPR016015;    Clusterin_C.
IPR016014;    Clusterin_N.
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PF01093;    Clusterin;    1.
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SM00035;    CLa;    1.
SM00030;    CLb;    1.
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PS00492;    CLUSTERIN_1;    1.
PS00493;    CLUSTERIN_2;    1.
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Created Date
Record Type
GAS predicted 
Sequence Annotation
SIGNAL        1     21       By similarity.
CHAIN        22    448       Clusterin.
CHAIN        22    226       Clusterin beta chain (By similarity).
CHAIN       227    447       Clusterin alpha chain (By similarity).
MOTIF        77     80       Nuclear localization signal.
MOTIF       442    446       Nuclear localization signal.
MOD_RES     393    393       Phosphoserine (By similarity).
MOD_RES     395    395       Phosphoserine (By similarity).
CARBOHYD    102    102       N-linked (GlcNAc...) (Probable).
CARBOHYD    144    144       N-linked (GlcNAc...) (Probable).
CARBOHYD    290    290       N-linked (GlcNAc...).
CARBOHYD    327    327       N-linked (GlcNAc...).
CARBOHYD    353    353       N-linked (GlcNAc...) (Probable).
CARBOHYD    373    373       N-linked (GlcNAc...) (Probable).
DISULFID    101    312       Interchain (between beta and alpha
                             chains) (By similarity).
DISULFID    112    304       Interchain (between beta and alpha
                             chains) (By similarity).
DISULFID    115    301       Interchain (between beta and alpha
                             chains) (By similarity).
DISULFID    120    294       Interchain (between beta and alpha
                             chains) (By similarity).
DISULFID    128    284       Interchain (between beta and alpha
                             chains) (By similarity).
MUTAGEN      78     79       KK->AV: Reduced nuclear location.
MUTAGEN     343    343       L->P: Abolishes interaction with XRCC6.
MUTAGEN     357    358       LL->RQ: Abolishes interaction with XRCC6.
MUTAGEN     361    361       L->R: Abolishes interaction with XRCC6.
MUTAGEN     371    371       L->R: Strongly reduced interaction with
MUTAGEN     442    443       RR->VV: Strongly reduced nuclear
CONFLICT     10     10       L -> M (in Ref. 3; AAB30623).
CONFLICT    335    336       RL -> TV (in Ref. 4; AAA37284).
CONFLICT    350    350       K -> N (in Ref. 4; AAA37284).
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Nucleotide Sequence
Length: 1663 bp   Go to nucleotide: FASTA
Protein Sequence
Length: 448 bp   Go to amino acid: FASTA
The verified Protein-Protein interaction information
Gene Symbol Ref Databases
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String database  
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