Identification and characterization of novel PAX8 mutations in Congenital Hypothyroidism(CH) in a Chinese population.
Identification and characterization of novel PAX8 mutations in Congenital Hypothyroidism(CH) in a Chinese population.
复制标题
中国人群先天性甲状腺功能减退症 (CH) 中 PAX8 新型突变的鉴定和特征分析
DOI：
10.18632/oncotarget.14419
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发表时间：
2017-01-31
期刊：
影响因子：
--
通讯作者：
Xing M
中科院分区：
文献类型：
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作者：
Liu S;Wang X;Zou H;Ge Y;Wang F;Wang Y;Yan S;Xia H;Xing M
目的 基于 PAX8 突变与甲状腺发育不全相关。我们的目标是在中国人群中因甲状腺发育不全而导致的一大群先天性甲状腺功能减退症 (CH) 中识别和表征 PAX8 突变。方法 我们通过对从血液中分离的基因组 DNA 上的 PAX8 整个编码区进行测序，对 453 名无关的中国甲状腺发育不全性 CH 患者进行了 PAX8 突变筛查。使用各种载体构建体和诱导诱变的细胞转染测定以及电泳迁移率变动测定用于研究所选突变对甲状腺球蛋白（TG）和甲状腺过氧化物酶（TPO）靶基因启动子处PAX8转录和结合活性的影响。结果 发现 5 个 PAX8 突变，突变率为 5/453 (1.1%)。我们在 PAX8 的关键配对结构域中选择了两个突变，并生成了突变体 D94N 和 G41V。我们证明G41V无法结合TG和TPO启动子中的特定序列并激活它们。 D94N 可以结合 TG 和 TPO 启动子并正常激活 TG 启动子转录，但不激活 TPO 启动子转录。我们还证明了 PAX8 突变体在损害野生型 PAX8 功能方面的显性负作用。结论 我们首次记录了中国人群 CH 中 PAX8 突变的患病率并描述了其功能。该研究具体证明了新突变 D94N 和 G41V 在损害 PAX8 功能中的作用，为遗传性 PAX8 缺陷作为 CH 的疾病机制提供了进一步的证据。
Objective Based on mutations in PAX8 is associated with thyroid dysgenesis. We aim to identify and characterize PAX8 mutations in a large cohort of congenital hypothyroidism(CH) from thyroid dysgenesis in Chinese population. Methods We screened 453 unrelated Chinese patients with CH from thyroid dysgenesis for PAX8 mutations by sequencing the whole coding regions of PAX8 on genomic DNA isolated from blood. Cell transfection assays using various vector constructs and induced mutagenesis as well as electrophoretic mobility shift assays were used to investigate the effects of selected mutations on the transcribing and binding activities of PAX8 at the promoters of target genes for thyroglobulin (TG) and thyroperoxidase (TPO). Results Five PAX8 mutations were found, yielding a mutation prevalence of 5/453 (1.1%). We selected two mutations in the critical paired domain of PAX8 and generated mutants D94N and G41V. We demonstrated G41V was unable to bind the specific sequence in the promoters of TG and TPO and activate them. D94N could bind to TG and TPO promoters and normally activate the TG promoter transcription but not the TPO promoter transcription. We also demonstrated a dominant negative role of the PAX8 mutants in impairing the function of the wild-type PAX8. Conclusion We for the first time documented the prevalence and characterized the function of PAX8 mutations in CH in Chinese population. The study specifically demonstrated the role of novel mutations D94N and G41V in impairing the function of PAX8, providing further evidence for genetic PAX8 defects as a disease mechanism in CH.