Galectin-4 is thought to play a role in the process of tumour conversion of cells of the alimentary tract and the breast tissue; however, its exact function remains unknown. With the aim of elucidating the structural basis of mouse galectin-4 (mGal-4) binding specificity, we have undertaken X-ray analysis of the N-terminal domain, CRD1, of mGal-4 in complex with lactose (the basic building block of known galectin-4 carbohydrate ligands). Crystals of CRD1 in complex with lactose were obtained using vapour-diffusion techniques. The crystals belong to tetragonal space group P42(1)2 with unit-cell parameters a = 91.1, b = 91.16, c = 57.10 A and preliminary X-ray diffraction data were collected to 3.2 A resolution. An optimized crystallization procedure and cryocooling protocol allowed us to extend resolution to 2.1 A. Structure refinement is currently under way; the initial electron-density maps clearly show non-protein electron density in the vicinity of the carbohydrate binding site, indicating the presence of one lactose molecule. The structure will help to improve understanding of the binding specificity and function of the potential colon cancer marker galectin-4.

• MeSH
• Amino Acid Motifs MeSH
• X-Ray Diffraction * MeSH
• Galectin 4 chemistry   metabolism   MeSH
• Crystallization MeSH
• Lactose chemistry   metabolism   MeSH
• Ligands MeSH
• Mice MeSH
• Biomarkers, Tumor chemistry   metabolism   MeSH
• Colonic Neoplasms chemistry   metabolism   MeSH
• Peptide Fragments chemistry   metabolism   MeSH
• Protein Structure, Tertiary * MeSH
• Binding Sites MeSH
• Animals MeSH
• Check Tag
• Mice MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Galectin 4 MeSH
• Lactose MeSH
• Ligands MeSH
• Biomarkers, Tumor MeSH
• Peptide Fragments MeSH