1. Identification of novel germline mutations in FUT7 and EXT1 linked with hereditary multiple exostoses.
- Author
-
Peng W, Li GF, Lin GW, Cheng XX, Zuo XY, Lin QH, Liu SQ, Li DJ, Lin DC, Yin JQ, Luo CL, Zhang YY, Xie XB, and Bei JX
- Abstract
Hereditary multiple exostoses (HME) is an autosomal dominant skeletal disorder primarily linked with mutations in Exostosin-1 (EXT1) and Exostosin-2 (EXT2) genes. However, not all HME cases can be explained by these mutations, and its pathogenic mechanisms are not fully understood. Herein, utilizing whole-exome sequencing and genetic screening with a family trio design, we identify two novel rare mutations co-segregating with HME in a Chinese family, including a nonsense mutation (c.204G>A, p.Trp68*) in EXT1 and a missense mutation (c.893T>G, p.Phe298Cys) in FUT7. Functional assays reveal that the FUT7 mutation affects the cellular localization of FUT7 protein and regulates cell proliferation. Notably, the simultaneous loss of fut7 and ext1 in a zebrafish model results in severe chondrodysplasia, indicating a functional link between FUT7 and EXT1 in chondrocyte regulation. Additionally, we unveil that FUT7 p.Phe298Cys reduces EXT1 expression through IL6/STAT3/SLUG axis at the transcription level and through ubiquitination-related proteasomal degradation at the protein level. Together, our findings not only identify novel germline mutations in FUT7 and EXT1 genes, but also highlight the critical interaction between these genes, suggesting a potential 'second-hit' mechanism over EXT1 mutations in HME pathogenesis. This insight enhances our understanding of the mechanisms underlying HME and opens new avenues for potential therapeutic interventions., Competing Interests: Competing interests: The authors declare no competing interests. Ethics approval and consent to participate: All methods used in the present study were in accordance with the relevant guidelines and regulations. This study was approved by the Ethics Committee for Clinical Research and Animal Trials of the First Affiliated Hospital of Sun Yat-sen University (permit NO. [2020]363). Informed consent was obtained from all the participants. All work involving zebrafish was reviewed and approved by the Animal Research Advisory Committee of the South China University of Technology., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)
- Published
- 2024
- Full Text
- View/download PDF