An antibody to p16INK4A recognizes a modified form of galectin-3.
Galectin-3 is a carbohydrate binding protein involved in multiple processes including cell-cycle regulation and apoptosis. The ability of galectin-3 to protect cells from apoptosis is dependent upon a region of the protein known as a BH-1 domain for its homology to the anti-apoptotic protein Bcl-2. Here, we show that a monoclonal antibody (MAb) to the human tumor suppressor protein p16INK4A recognizes a post-translationally modified form of human galectin-3. The modified form is detectable in only a subset of cell types expressing galectin-3, indicating that the modification is cell-type-specific. Although there is little amino acid sequence homology between p16INK4a and galectin-3, we show by epitope mapping that the modification directly affects the structure of galectin-3's BH-1 domain. Elucidation of the nature of this modification might provide further insight into galectin-3 function.
Gump
J
J
Department of Molecular Physiology and Biophysics, University of Vermont, Burlington, VT 05405, USA.
Koh
J
J
D000943:Antigens, Differentiation / Q000737:chemistry / Q000276:immunology*; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000276:immunology*; D037502:Galectin 3; D006801:Humans; D016056:Immunodominant Epitopes / Q000737:chemistry / Q000276:immunology; D013329:Structure-Activity Relationship
D000943:Antigens, Differentiation; D019941:Cyclin-Dependent Kinase Inhibitor p16; D037502:Galectin 3; D016056:Immunodominant Epitopes