P63 alpha mutations lead to aberrant splicing of keratinocyte growth factor receptor in the Hay-Wells syndrome.
p63, a p53 family member, is required for craniofacial and limb development as well as proper skin differentiation. However, p63 mutations associated with the ankyloblepharon-ectodermal dysplasia-clefting (AEC) syndrome (Hay-Wells syndrome) were found in the p63 carboxyl-terminal region with a sterile alpha-motif. By two-hybrid screen we identified several proteins that interact with the p63alpha carboxyl terminus and its sterile alpha-motif, including the apobec-1-binding protein-1 (ABBP1). AEC-associated mutations completely abolished the physical interaction between ABBP1 and p63alpha. Moreover the physical association of p63alpha and ABBP1 led to a specific shift of FGFR-2 alternative splicing toward the K-SAM isoform essential for epithelial differentiation. We thus propose that a p63alpha-ABBP1 complex differentially regulates FGFR-2 expression by supporting alternative splicing of the K-SAM isoform of FGFR-2. The inability of mutated p63alpha to support this splicing likely leads to the inhibition of epithelial differentiation and, in turn, accounts for the AEC phenotype.
Pubmed ID: 12692135 RIS Download
Abnormalities, Multiple | Animals | Cell Differentiation | DNA-Binding Proteins | Ectodermal Dysplasia | Epithelial Cells | Gene Expression Regulation | Genes, Tumor Suppressor | Heterogeneous-Nuclear Ribonucleoprotein Group A-B | Humans | Membrane Proteins | Mice | Mouth Abnormalities | Mutation | Phosphoproteins | Protein Binding | Protein Isoforms | Protein Splicing | RNA-Binding Proteins | Receptor, Fibroblast Growth Factor, Type 2 | Receptors, Fibroblast Growth Factor | Syndrome | Trans-Activators | Transcription Factors | Tumor Suppressor Proteins | Two-Hybrid System Techniques