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From Proteopedia
Structure of sugar modified epidermal growth factor-like repeat 12 of mouse Notch-1 receptor
Structural highlights
FunctionNOTC1_MOUSE Functions as a receptor for membrane-bound ligands Jagged1, Jagged2 and Delta1 to regulate cell-fate determination. Upon ligand activation through the released notch intracellular domain (NICD) it forms a transcriptional activator complex with RBPJ/RBPSUH and activates genes of the enhancer of split locus. Affects the implementation of differentiation, proliferation and apoptotic programs. Involved in angiogenesis; negatively regulates endothelial cell proliferation and migration and angiogenic sprouting. Involved in the maturation of both CD4+ and CD8+ cells in the thymus. Important for follicular differentiation and possibly cell fate selection within the follicle. During cerebellar development, functions as a receptor for neuronal DNER and is involved in the differentiation of Bergmann glia. Represses neuronal and myogenic differentiation. May play an essential role in postimplantation development, probably in some aspect of cell specification and/or differentiation. May be involved in mesoderm development, somite formation and neurogenesis. May enhance HIF1A function by sequestering HIF1AN away from HIF1A. Required for the THBS4 function in regulating protective astrogenesis from the subventricular zone (SVZ) niche after injury. Involved in determination of left/right symmetry by modulating the balance between motile and immotile (sensory) cilia at the left-right organiser (LRO).[1] [2] [3] [4] Publication Abstract from PubMedNotch receptors are cell surface glycoproteins that play key roles in a number of developmental cascades in metazoa. The extracellular domains of Notch-1 receptors are composed of 36 tandem epidermal growth factor (EGF)-like repeats, many of which are modified at highly conserved consensus sites by an unusual form of O-glycan, with O-fucose. The O-fucose residues on certain EGF repeats may be elongated. In mammalian cells this can be a tetrasaccharide, Siaalpha2,3Galbeta1,4GlcNAcbeta1,3Fucalpha1-->. This elongation process is initiated by the action of O-fucose-specific beta1,3 N-acetylglucosaminyltransferases of the Fringe family. There is evidence that the addition of GlcNAc by Fringe serves as an essential modulator of the interaction of Notch with its ligands and the triggering of activation. Here we describe the efficient synthesis, folding, and structural characterization of EGF repeat 12 (EGF 12) of a mouse Notch-1 receptor bearing different O-fucose glycan chains. We demonstrate that the three disulfide bonds, Cys(456)-Cys(467) (C1-C3), Cys(461)-Cys(476) (C2-C4), and Cys(478)-Cys(487) (C5-C6) were correctly formed in the nonglycosylated as well as the O-fucosylated forms of EGF 12. Three-dimensional structural studies by NMR reveal that the methyl group of fucose is in close contact with ILe(475), Met(477), Pro(478) residues and this stabilizes the conformation of the antiparallel beta-sheet of EGF 12. The addition of the GlcNAc residue on O-fucosylated EGF 12 induces a significant conformational change in the adjacent tripeptide sequence, Gln(462)Asn(463)Asp(464), which is a motif involved in the natural, enzymatic O-fucosylation at the conserved site (Cys(461)X(4)Ser/ThrCys(467)). Chemical synthesis, folding, and structural insights into O-fucosylated epidermal growth factor-like repeat 12 of mouse Notch-1 receptor.,Hiruma-Shimizu K, Hosoguchi K, Liu Y, Fujitani N, Ohta T, Hinou H, Matsushita T, Shimizu H, Feizi T, Nishimura S J Am Chem Soc. 2010 Oct 27;132(42):14857-65. PMID:20883017[5] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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