Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P17931 (galectin-3)
 2,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Human Mac-2-binding protein (Mac-2-BP) is a secreted glycoprotein that is widely expressed. It binds to the human macrophage-associated lectin Mac-2 and has been suggested to have a role in host defence. Mouse cyclophilin C-associated protein (mCyCAP) is also a secreted glycoprotein that binds with high affinity to cyclophilin C in the absence of the immunosuppressive drug cyclosporin A. The two proteins share a similar domain structure and considerable sequence identity, including a highly conserved scavenger receptor cysteine-rich domain, and both of them exert their function within the immune system. To elucidate whether these molecules are also functional homologues, we compared their ligand binding properties using cell lines which express Mac-2-BP or mCyCAP as well as transfected cell lines stably expressing mCyCAP or a mutant version lacking the scavenger domain. These experiments show that Mac-2-BP is unable to bind to either human or mouse cyclophilin C and thatmCyCAP cannot bind to Mac-2. The scavenger domain is not required for the interaction between mCyCAP and cyclophilin C. We conclude that these proteins may be part of a larger family of proteins of immunological importance in which closer functional homologues might exists.
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PMID:Distinct ligand binding properties of Mac-2-binding protein and mouse cyclophilin [correction of mousephilin] C-associated protein. 1159 84

Cyclophilin C-associated protein (CyCAP) or Mac-2 binding protein has been identified as a binding protein for cyclophilin C in mice and for Mac-2 (galectin-3) in human, suggesting its multiple binding activity to proteins. In the present study, using specific anti-rat-CyCAP antibody, we found that CyCAP colocalizes with calnexin at the location near the nuclear envelope, however CyCAP does not have colocalization with calreticulin. In senescent fibroblasts and interferon-gamma (IFNgamma) treated fibroblasts, both calnexin and CyCAP form larger polymers and are released from the endoplasmic reticulum (ER) through the cellular membrane to the extracellular area. Immunoprecipitation studies further confirm that the release of calnexin is through binding to CyCAP. Further, we found that tissue transglutaminase (tTG) protein is decreased, however not at the RNA level, in CyCAP null fibroblasts, which suggests that CyCAP is involved in tTG post-translational modification. Our data give novel evidence that CyCAP regulates the post-translational modification of tTG through its colocalization with calnexin in ER.
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PMID:Cyclophilin C-associated protein/Mac-2 binding protein colocalizes with calnexin and regulates the expression of tissue transglutaminase. 2004 54