Gpr177-mediated Wnt Signaling Is Required for Secondary Palate Development.
Cleft palate represents one of the major congenital birth defects in humans. Despite the essential roles of ectodermal canonical Wnt and mesenchymal Wnt signaling in the secondary palate development, the function of mesenchymal canonical Wnt activity in secondary palate development remains elusive. Here we show that Gpr177, a highly conserved transmembrane protein essential for Wnt trafficking, is required for secondary palate development. Gpr177 is expressed in both epithelium and mesenchyme of palatal shelves during mouse development. Wnt1(Cre)-mediated deletion of Gpr177 in craniofacial neural crest cells leads to a complete cleft secondary palate, which is formed mainly due to aberrant cell proliferation and increased cell death in palatal shelves. By BATGAL staining, we reveal an intense canonical Wnt activity in the anterior palate mesenchyme of E12.5 wild-type embryos but not in Gpr177(Wnt1-Cre) embryos, suggesting that mesenchymal canonical Wnt signaling activated by Gpr177-mediated mesenchymal Wnts is critical for secondary palate development. Moreover, phosphorylation of JNK and c-Jun is impaired in the Gpr177(Wnt1-Cre) palate and is restored by implantation of Wnt5a-soaked beads in the in vitro palate explants, suggesting that Gpr177 probably regulates palate development via the Wnt5a-mediated noncanonical Wnt pathway in which c-Jun and JNK are involved. Importantly, certain cellular processes and the altered gene expression in palates lacking Gpr177 are distinct from that of the Wnt5a mutant, further demonstrating involvement of other mesenchymal Wnts in the process of palate development. Together, these results suggest that mesenchymal Gpr177 is required for secondary palate development by regulating and integrating mesenchymal canonical and noncanonical Wnt signals.
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China Cluster for Craniofacial Development and Regeneration Research, Institute of Oral Biosciences and BK21 Program, Chonbuk National University School of Dentistry, Jeonju, South Korea.
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Liu
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China.
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Wang
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China.
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Zhao
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China.
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Yuan
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China.
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Yang
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China.
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Li
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China.
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Qiu
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China zunyi_zhang@idrbio.org xiao_jingzhu@hznu.edu.cn.
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Zhu
Institute of Developmental and Regenerative Biology, College of Life and Environmental Science, Hangzhou Normal University, Zhejiang, China Key Laboratory of Mammalian Organogenesis and Regeneration, Zhejiang, China.
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Zhang
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D016923:Cell Death / Q000502:physiology; D049109:Cell Proliferation; D002972:Cleft Palate / Q000196:embryology; D004848:Epithelium / Q000196:embryology; D047908:Intracellular Signaling Peptides and Proteins / Q000502:physiology*; D048670:MAP Kinase Kinase 4 / Q000187:drug effects / Q000378:metabolism; D008648:Mesoderm / Q000196:embryology; D051379:Mice; D018345:Mice, Knockout; D008822:Mice, Transgenic; D009432:Neural Crest / Q000196:embryology; D009924:Organ Culture Techniques; D010159:Palate / Q000196:embryology*; D016755:Proto-Oncogene Proteins c-jun / Q000187:drug effects / Q000378:metabolism; D043562:Receptors, G-Protein-Coupled / Q000502:physiology*; D051153:Wnt Proteins / Q000494:pharmacology; D060449:Wnt Signaling Pathway / Q000502:physiology*; D000071818:Wnt-5a Protein
C545200:Gpr177 protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D016755:Proto-Oncogene Proteins c-jun; D043562:Receptors, G-Protein-Coupled; D051153:Wnt Proteins; D000071818:Wnt-5a Protein; C438615:Wnt5a protein, mouse; D048670:MAP Kinase Kinase 4
Wnt5a; Wntless; canonical; cleft palate; craniofacial; knockout mice