Sema3E is required for migration of cranial neural crest cells in zebrafish: Implications for the pathogenesis of CHARGE syndrome
Sema3E is required for migration of cranial neural crest cells in zebrafish: Implications for the pathogenesis of CHARGE syndrome
复制标题
斑马鱼颅神经嵴细胞迁移需要 Sema3E：对 CHARGE 综合征发病机制的影响。
DOI：
10.1111/iep.12331
复制
发表时间：
2019-08-01
影响因子：
3
通讯作者：
Xu, Hong A.
中科院分区：
文献类型：
--
作者：
Liu, Zhi-Zhi;Guo, Jingjing;Xu, Hong A.
CHARGE综合征是一种颅面结构、心血管和生殖系统多种畸形的先天性疾病，主要受到染色质解旋酶DNA结合蛋白7（CHD7）内功能丧失突变引起的神经嵴缺陷的影响。然而，许多 CHARGE 综合征患者的 CHD7 检测呈阴性。据报道，Semaphorin 3E (sema3E) 基因在 CHARGE 综合征患者中发生突变。然而，其在CHARGE综合征发病机制中的作用尚未得到实验验证。在这里，我们报道了 sema3E 的敲低导致严重的颅面畸形，包括小眼睛、有缺陷的软骨和斑马鱼胚胎中耳石数量异常，这类似于 CHARGE 综合征的主要特征。进一步分析表明，迁移性颅神经嵴细胞分散在后脑区域，并且在 sema3E 敲低后，迁移后神经嵴细胞在咽弓中减少。值得注意的是，对神经嵴细胞标记的转基因鱼系 sox10:EGFP 的免疫染色和延时成像分析表明，颅神经嵴细胞的迁移受到严重损害，并且许多细胞在 sema3E 敲低后被错误路由。此外，表达sox10的颅神经嵴细胞分散在chd7纯合突变体中，其表现出sema3E突变体的表型。 sema3E的过表达可以挽救chd7纯合子中分散的颅神经嵴细胞的表型，表明chd7可能控制sema3E的表达来调节颅神经嵴细胞的迁移。总的来说，我们的数据表明 sema3E 通过调节颅神经嵴细胞迁移参与 CHARGE 综合征的发病机制。
CHARGE syndrome is a congenital disorder with multiple malformations in the craniofacial structures, and cardiovascular and genital systems, which are mainly affected by neural crest defects caused by loss-of-function mutations within chromodomain helicase DNA-binding protein 7 (CHD7). However, many patients with CHARGE syndrome test negative for CHD7. Semaphorin 3E (sema3E) is a gene reported to be mutated in patients with CHARGE syndrome. However, its role in the pathogenesis of CHARGE syndrome has not been verified experimentally. Here, we report that the knockdown of sema3E results in severe craniofacial malformations, including small eyes, defective cartilage and an abnormal number of otoliths in zebrafish embryos, which resemble the major features of CHARGE syndrome. Further analysis reveals that the migratory cranial neural crest cells are scattered in the region of the hindbrain, and the postmigratory neural crest cells are reduced in the pharyngeal arches upon sema3E knockdown. Notably, immunostaining and time-lapse imaging analyses of a neural crest cell-labelled transgenic fish line, sox10:EGFP, show that the migration of cranial neural crest cells is severely impaired, and many of these cells are misrouted upon sema3E knockdown. Furthermore, the sox10-expressing cranial neural crest cells are scattered in chd7 homozygous mutants, which phenocopied the phenotype in sema3E morphants. Overexpression of sema3E rescues the phenotype of scattered cranial neural crest cells in chd7 homozygotes, indicating that chd7 may control the expression of sema3E to regulate cranial neural crest cell migration. Collectively, our data demonstrate that sema3E is involved in the pathogenesis of CHARGE syndrome by modulating cranial neural crest cell migration.