FGF domain, beta-trefoil fold, found in acidic and basic fibroblast growth factor (FGF) superfamily; The FGF superfamily includes FGF1-23 and similar proteins. FGFs are mitogens, which stimulate growth or differentiation of cells of mesodermal or neuroectodermal origin. They play essential roles in patterning and differentiation during vertebrate embryogenesis and have neurotrophic activities. FGFs have a high affinity for heparan sulfate proteoglycans and require heparan sulfate to activate one of four cell surface FGF receptors. Upon binding to FGF, the receptors dimerize, and their intracellular tyrosine kinase domains become active. The structure of FGFs is typical of the beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry.

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gi 1878422941  31 APNlSSPLQSSNWGNPRRYVHLRSTTEFNNFYLEISLTGHVRKTTHRGSY 80
Cdd:cd23333     1 FPN-ASPLLGPNWGNPRRLIHLYTSTDRNSYHLQINPDGHVDGTPHQTIY 49

FGF domain, beta-trefoil fold, found in fibroblast growth factor 23 (FGF23) and similar proteins; FGF23, also called phosphatonin, or tumor-derived hypophosphatemia-inducing factor (HYPF), is a regulator of phosphate homeostasis. It inhibits renal tubular phosphate transport by reducing SLC34A1 levels. It upregulates EGR1 expression in the presence of alpha-Klotho (KL). It acts directly on the parathyroid to decrease PTH secretion. FGF23 acts as a regulator of vitamin-D metabolism. It negatively regulates osteoblast differentiation and matrix mineralization. FGF23 interacts with fibroblast growth factor receptors, FGFR1, FGFR2, FGFR3, and FGFR4. Affinity between fibroblast growth factors (FGFs) and their receptors is increased by KL and heparan sulfate glycosaminoglycans that function as coreceptors. FGF23 contains a FGF domain with beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry.

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                  ....*....|....*....|....*....|....*....|....*....|
gi 1878422941  31 APNlSSPLQSSNWGNPRRYVHLRSTTEFNNFYLEISLTGHVRKTTHRGSY 80
Cdd:cd23333     1 FPN-ASPLLGPNWGNPRRLIHLYTSTDRNSYHLQINPDGHVDGTPHQTIY 49

FGF domain, beta-trefoil fold, found in fibroblast growth factor 23 (FGF23) and similar proteins; FGF23, also called phosphatonin, or tumor-derived hypophosphatemia-inducing factor (HYPF), is a regulator of phosphate homeostasis. It inhibits renal tubular phosphate transport by reducing SLC34A1 levels. It upregulates EGR1 expression in the presence of alpha-Klotho (KL). It acts directly on the parathyroid to decrease PTH secretion. FGF23 acts as a regulator of vitamin-D metabolism. It negatively regulates osteoblast differentiation and matrix mineralization. FGF23 interacts with fibroblast growth factor receptors, FGFR1, FGFR2, FGFR3, and FGFR4. Affinity between fibroblast growth factors (FGFs) and their receptors is increased by KL and heparan sulfate glycosaminoglycans that function as coreceptors. FGF23 contains a FGF domain with beta-trefoil fold, which is characterized by 12 beta strands folded into three similar trefoil subdomains (alpha, beta, and gamma) associated to give an overall structure with pseudo-3-fold symmetry.

                          10        20        30        40        50
                  ....*....|....*....|....*....|....*....|....*....|
gi 1878422941  31 APNlSSPLQSSNWGNPRRYVHLRSTTEFNNFYLEISLTGHVRKTTHRGSY 80
Cdd:cd23333     1 FPN-ASPLLGPNWGNPRRLIHLYTSTDRNSYHLQINPDGHVDGTPHQTIY 49