Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology & National Center of Stomatology & National Clinical Research Center for Oral Diseases & National Engineering Laboratory for Digital and Material Technology of Stomatology & Central Laboratory, Peking University School and Hospital of Stomatology, Beijing, China.
Mol Genet Genomic Med. 2023 Apr;11(4):e2119. doi: 10.1002/mgg3.2119. Epub 2022 Nov 29.
Hypohidrotic ectodermal dysplasia (HED) mainly results from gene mutations in the EDA/EDAR/NF-κB pathway. Function analysis of the mutations in the collagen domain of ectodysplasin A (EDA)result in HED has been rarely studied. This study aimed at determining the mechanism by which the novel collagen domain mutation of EDA results in HED.
We analyzed the DNAs from a Chinese family with HED and performed bioinformatics analysis. A new three-dimensional structure model of the EDA trimer was built and used to predict the effect of the mutations on EDA. We performed a western blot to detect EDA1 proteins in cell lysates and supernatants. We then performed coimmunoprecipitation to determine whether the mutation would affect the interaction of EDA1 with the EDA receptor (EDAR). Dual luciferase reporter assay and immunofluorescence were performed to detect the effect of the mutant EDA1 protein on nuclear factor kappa B (NF-κB) activation.
A novel missense mutation (c.593G > A, p. Gly198Glu) in the collagen domain of EDA was detected. The mutation was predicted to be disease-causing. A three-dimensional structure model of the EDA trimer was first built in this study, in which the mutation site is located around the receptor binding domain. Functional studies showed that there was no difference in the secretion activity between the mutant EDA1 and the wild-type EDA1. However, the receptor-binding activity and the transcription activation of NF-κB were impaired by the mutation.
We identified a novel mutation (c.593G > A, p. Gly198Glu) in the collagen domain of EDA. Bioinformatics analysis and functional studies showed this mutation was damaging, indicating that mutations in the collagen domain of EDA could result in HED by affecting the receptor-binding activity of EDA and the transcriptional activity of NF-κB.
少汗型外胚层发育不全（HED）主要由 EDA/EDAR/NF-κB 通路中的基因突变引起。EDA 胶原结构域突变导致 HED 的功能分析研究甚少。本研究旨在确定 EDA 胶原结构域新突变导致 HED 的机制。
我们分析了一个 HED 中国家系的 DNA，并进行了生物信息学分析。构建了 EDA 三聚体的新三维结构模型，并用于预测突变对 EDA 的影响。我们进行了 Western blot 检测细胞裂解物和上清液中的 EDA1 蛋白。然后进行了共免疫沉淀实验，以确定突变是否会影响 EDA1 与 EDA 受体（EDAR）的相互作用。双荧光素酶报告基因检测和免疫荧光实验检测突变型 EDA1 蛋白对核因子 κB（NF-κB）激活的影响。
检测到 EDA 胶原结构域中的一个新错义突变（c.593G>A，p.Gly198Glu）。该突变被预测为致病突变。本研究首次构建了 EDA 三聚体的三维结构模型，突变位点位于受体结合域周围。功能研究表明，突变型 EDA1 和野生型 EDA1 的分泌活性没有差异。然而，该突变损害了受体结合活性和 NF-κB 的转录激活。
我们在 EDA 的胶原结构域中鉴定出一个新的突变（c.593G>A，p.Gly198Glu）。生物信息学分析和功能研究表明该突变是有害的，表明 EDA 胶原结构域的突变可通过影响 EDA 的受体结合活性和 NF-κB 的转录活性导致 HED。
