Functional study of novel PAX9 variants: The paired domain and non-syndromic oligodontia
Functional study of novel PAX9 variants: The paired domain and non-syndromic oligodontia
复制标题
新 PAX9 变体的功能研究：配对结构域和非综合征性少牙症
DOI：
10.1111/odi.13684
复制
发表时间：
2020-11-03
期刊：
影响因子：
3.8
通讯作者：
Han, Dong
中科院分区：
文献类型：
--
作者：
Sun, Kai;Yu, Miao;Han, Dong
目的探讨非综合征性少牙患者中配对盒9（PAX 9）基因的致病性变体以及这些变体的功能影响。对象和方法利用全外显子组测序和桑格测序来检测80名诊断为非综合征性少牙患者的基因变体。结果在PAX 9基因中发现了3个新的突变体，包括2个移码突变体（c.211_212insA; p.I71Nfs*246和c.236_237insAC; p.T80Lfs*6）和1个错义突变体（c.229C > G; p.R77G）。家系共分离证实了常染色体显性遗传模式。构象分析表明，这些变异体位于配对结构域，并可能导致PAX 9蛋白的相应结构损伤。荧光显微镜显示移码变异体的异常亚细胞定位，和荧光素酶测定显示，所有变体中骨形态发生蛋白4（BMP 4）基因的下游反式激活活性均受损。结论我们的研究结果拓宽了非综合征性少牙患者PAX 9变体的范围，并支持配对结构域结构损伤和显性负效应可能是PAX 9的潜在机制。相关的非综合征性少牙症我们的研究结果将有助于遗传诊断和咨询，并有助于为精确的口腔健康疗法奠定基础。
Objectives To investigate pathogenic variants of the paired box 9 (PAX9) gene in patients with non-syndromic oligodontia, and the functional impact of these variants.Subjects and Methods Whole exome sequencing and Sanger sequencing were utilized to detect gene variants in a cohort of 80 patients diagnosed with non-syndromic oligodontia. Bioinformatic and conformational analyses, fluorescence microscopy and luciferase reporter assay were employed to explore the functional impact.Results We identified three novel variants in the PAX9, including two frameshift variants (c.211_212insA; p.I71Nfs*246 and c.236_237insAC; p.T80Lfs*6), and one missense variant (c.229C > G; p.R77G). Familial co-segregation verified an autosomal-dominant inheritance pattern. Conformational analyses revealed that the variants resided in the paired domain, and could cause corresponding structural impairment of the PAX9 protein. Fluorescence microscopy showed abnormal subcellular localizations of frameshift variants, and luciferase assay showed impaired downstream transactivation activities of the bone morphogenetic protein 4 (BMP4) gene in all variants.Conclusions Our findings broaden the spectrum of PAX9 variants in patients with non-syndromic oligodontia and support that paired domain structural impairment and the dominant-negative effect are likely the underlying mechanisms of PAX9-related non-syndromic oligodontia. Our findings will facilitate genetic diagnosis and counselling, and help lay the foundation for precise oral health therapies.