title: Colocalization and identification of interaction sites between IGFBP-3 and GalNAc-T14.
abstract: GalNAc-T14 was identified as a novel IGFBP-3 binding partner in previous studies. Here, we furtherly confirmed the interaction between them by confocal microscopy, and identified the binding domain and probable interaction sites of GalNAc-T14 with IGFBP-3. The result of subcellular localization indicated that GalNAc-T14 was distributed in the cytosol, whereas IGFBP-3 existed in the cytosol and nucleolus. Confocal analyses demonstrated that IGFBP-3 and GalNAc-T14 colocalized in the cytosol. The result from yeast two hybrid assay showed that the C terminus of GalNAc-T14 (408-552aa) was essential for the interaction between GalNAc-T14 and IGFBP-3, especially Tyr(408), Pro(409), and Glu(410) of GalNAc-T14 may play key roles in the interaction with IGFBP-3. In conclusion, these studies demonstrated that IGFBP-3 and GalNAc-T14 are colocalized in MCF-7 cells and confirmed the interaction between IGFBP-3 and GalNAc-T14. This interaction may play an important role in the functional regulation of IGFBP-3.
authors.affiliation: College of Life Sciences, Hebei University, Baoding, Hebei 071002, PR China. dawnwuchen@163.com
authors.forename: Chen
authors.initials: C
authors.lastname: Wu
authors.forename: Si-Si
authors.initials: SS
authors.lastname: Ma
authors.forename: Jian-Feng
authors.initials: JF
authors.lastname: Ge
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Wang
authors.forename: Huan-Na
authors.initials: HN
authors.lastname: Tian
authors.forename: Xiao-Bo
authors.initials: XB
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Zhang
authors.forename: Fang-Ming
authors.initials: FM
authors.lastname: Liu
authors.forename: Xiao-Kang
authors.initials: XK
authors.lastname: Zhang
authors.forename: Qin-Jian
authors.initials: QJ
authors.lastname: Li
mesh_terms: D017209:Apoptosis; D001943:Breast Neoplasms / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*; D018613:Microscopy, Confocal; D008958:Models, Molecular; D017350:N-Acetylgalactosaminyltransferases / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*; D054730:Protein Interaction Domains and Motifs; D020798:Two-Hybrid System Techniques
chemical_list: C515497:IGFBP3 protein, human; D018972:Insulin-Like Growth Factor Binding Protein 3; D017350:N-Acetylgalactosaminyltransferases; C471038:UDP-N-acetyl-D-galactosamine polypeptide N-acetylgalactosaminyltransferase 14, human