Additive effects on craniofacial development upon conditional ablation of PDGFRα and SHP2 in the mouse neural crest lineage
BackgroundActivity of the receptor tyrosine kinase PDGFR and the tyrosine phosphatase SHP2 are critical for vertebrate craniofacial development. We sought to determine the effect of SHP2 binding to PDGFR via phenotypic and biochemical analyses of an allelic series of mouse embryos with combined loss of both proteins in the neural crest lineage. ResultsWe demonstrated that SHP2 preferentially binds PDGFR/ homodimers among the three PDGFR dimers. Analysis of allelic series mutant embryos revealed increased cell death in the lateral nasal and maxillary processes at E10.5, variably penetrant facial blebbing, facial hemorrhaging, midline clefting and loss of the mandibular region at E13.5, and widespread craniofacial bone and cartilage defects at birth. Further, we showed that loss of SHP2 leads to increased phosphorylation of PDGFR and the downstream effector Erk1/2 in E10.5 allelic series mutant embryo lysates. ConclusionsTogether, our findings demonstrate additive effects on craniofacial development upon conditional ablation of PDGFR and SHP2 in the mouse neural crest lineage and indicate that SHP2 may negatively and positively regulate PDGFR signaling through distinct mechanisms.