N-Acetylgalactosaminyltransferase 14, a novel insulin-like growth factor binding protein-3 binding partner.
Insulin-like growth factor binding protein-3 (IGFBP-3) is known to inhibit cell proliferation and induce apoptosis in IGF-dependent and IGF-independent manners, but the mechanism underlying IGF-independent effects is not yet clear. In a yeast two-hybrid assay, IGFBP-3 was used as the bait to screen a human fetal liver cDNA library for it interactors that may potentially mediate IGFBP-3-regulated functions. N-Acetylgalactosaminyltransferase 14 (GalNAc-T14), a member of the GalNAc-Tases family, was identified as a novel IGFBP-3 binding partner. This interaction involved the ricin-type beta-trefoil domain of GalNAc-T14. The interaction between IGFBP-3 and GalNAc-T14 was reconfirmed in vitro and in vivo, using GST pull-down, co-immunoprecipitation and mammalian two-hybrid assays. Our findings may provide new clues for further study on the mechanism behind the IGF-independent effects of IGFBP-3 promoting apoptosis. The role of GalNAc-T14 as an intracellular mediator of the effects of IGFBP-3 need to be verified in future studies.
Wu
Chen
C
Institute of Basic Medical Sciences, Taiping Road 27, Beijing 100850, PR China; College of Life Sciences, Hebei University, Baoding, Hebei 100072, PR China.
Yao
Guangyin
G
Zou
Minji
M
Chen
Guangyu
G
Wang
Min
M
Liu
Jingqian
J
Wang
Jiaxi
J
Xu
Donggang
D
D001665:Binding Sites; D002460:Cell Line; D004789:Enzyme Activation; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000378:metabolism*; D007668:Kidney / Q000378:metabolism*; D017350:N-Acetylgalactosaminyltransferases / Q000378:metabolism*; D011485:Protein Binding; D025941:Protein Interaction Mapping
D018972:Insulin-Like Growth Factor Binding Protein 3; D017350:N-Acetylgalactosaminyltransferases