Specific deletion of Axin1 leads to activation of β-catenin/BMP signaling resulting in fibular hemimelia phenotype in mice
Abstract
Axin1 is a key regulator of canonical Wnt signaling pathway. Roles of Axin1 in skeletal development and in disease occurrence have not been fully defined. Here, we report that Axin1 is essential for lower limb development. Specific deletion of Axin1 in limb mesenchymal cells leads to fibular hemimelia (FH)-like phenotype, associated with tarsal coalition. Further studies demonstrate that FH disease is associated with additional defects in Axin1 knockout (KO) mice, including decreased osteoclast formation and defects in angiogenesis. We then provide in vivo evidence showing that Axin1 controls limb development through both canonical β-catenin and BMP signaling pathways. We demonstrate that inhibition of β-catenin or BMP signaling could significantly reverse the FH phenotype in mice. Together, our findings reveal that integration of β-catenin and BMP signaling by Axin1 is required for lower limb development. Defect in Axin1 signaling could lead to the development of FH disease.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting file; Source Data files have been provided for Figures.
Article and author information
Author details
Funding
National Natural Science Foundation of China (82030067)
- Di Chen
National Natural Science Foundation of China (82161160342)
- Di Chen
National Natural Science Foundation of China (82172397)
- Liping Tong
National Natural Science Foundation of China (81974320)
- Zhenlin Zhang
National Key Research and Development Program of China (2021YFB3800800)
- Di Chen
National Key Research and Development Program of China (2021YFB3800800)
- Liping Tong
Guangdong Basic and Applied Basic Research Foundation (2021A1515111075)
- Dan Yi
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (SIAT-IACUC-200302-YYS-CD-A1063) of the Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences.
Copyright
© 2022, Xie et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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