title: Multiple consequences of a single amino acid pathogenic RTK mutation: the A391E mutation in FGFR3.
abstract: The A391E mutation in fibroblast growth factor receptor 3 (FGFR3) is the genetic cause for Crouzon syndrome with Acanthosis Nigricans. Here we investigate the effect of this mutation on FGFR3 activation in HEK 293 T cells over a wide range of fibroblast growth factor 1 concentrations using a physical-chemical approach that deconvolutes the effects of the mutation on dimerization, ligand binding, and efficiency of phosphorylation. It is believed that the mutation increases FGFR3 dimerization, and our results verify this. However, our results also demonstrate that the increase in dimerization is not the sole effect of the mutation, as the mutation also facilitates the phosphorylation of critical tyrosines in the activation loop of FGFR3. The activation of mutant FGFR3 is substantially increased due to a combination of these two effects. The low expression of the mutant, however, attenuates its signaling and may explain the mild phenotype in Crouzon syndrome with Acanthosis Nigricans. The results presented here provide new knowledge about the physical basis behind growth disorders and highlight the fact that a single RTK mutation may affect multiple steps in RTK activation.
authors: Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland, USA.
authors: Fenghao
authors: F
authors: Chen
authors: Sarvenaz
authors: S
authors: Sarabipour
authors: Kalina
authors: K
authors: Hristova
mesh_terms: D000052:Acanthosis Nigricans / Q000235:genetics* / Q000473:pathology*; D019943:Amino Acid Substitution / Q000235:genetics*; D003394:Craniofacial Dysostosis / Q000235:genetics* / Q000473:pathology*; D005786:Gene Expression Regulation; D057809:HEK293 Cells; D006801:Humans; D009154:Mutation; D010766:Phosphorylation / Q000235:genetics; D011485:Protein Binding / Q000235:genetics; D055503:Protein Multimerization / Q000235:genetics; D051498:Receptor, Fibroblast Growth Factor, Type 3 / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D013329:Structure-Activity Relationship
chemical_list: C496365:FGFR3 protein, human; D051498:Receptor, Fibroblast Growth Factor, Type 3