Interaction of a novel cysteine and histidine-rich cytoplasmic protein with galectin-3 in a carbohydrate-independent manner.
We have used the yeast two-hybrid system to search for cytoplasmic proteins that might assist in the intracellular trafficking of the soluble beta-galactoside-binding protein, galectin-3. We utilised as bait murine full-length galectin-3 to screen a murine 3T3 cDNA library. Several interacting clones were found to encode a partial open reading frame and a full-length clone was obtained by rapid amplification of cDNA ends methodology. In various assays in vitro the novel protein was shown to bind galectin-3 in a carbohydrate-independent manner. The novel protein contains an unusually high content of cysteine and histidine residues and shows significant sequence homologies with several metal ion-binding motifs present in known proteins. Confocal immunofluorescence microscopy of permeabilised 3T3 cells shows a prominent perinuclear, as well as cytoplasmic, localisation of the novel protein.
Menon
R P
RP
Divisions of Protein Structure and Membrane Biology, National Institute for Medical Research, Mill Hill, London, UK.
Strom
M
M
Hughes
R C
RC
D016475:3T3 Cells; D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D000818:Animals; D000943:Antigens, Differentiation / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D050260:Carbohydrate Metabolism; D002467:Cell Nucleus / Q000737:chemistry; D003001:Cloning, Molecular; D017124:Conserved Sequence / Q000235:genetics; D003545:Cysteine / Q000235:genetics / Q000378:metabolism*; D003593:Cytoplasm / Q000737:chemistry*; D037502:Galectin 3; D006639:Histidine / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008856:Microscopy, Fluorescence; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D011506:Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D016415:Sequence Alignment; D020798:Two-Hybrid System Techniques
D000943:Antigens, Differentiation; C406869:Cyhr1 protein, mouse; D037502:Galectin 3; D010446:Peptide Fragments; D011506:Proteins; D012333:RNA, Messenger; D006639:Histidine; D003545:Cysteine