Institute of Molecular Biology and Medicine, Université Libre de Bruxelles, 6041, Gosselies, Belgium.
Institute of Biochemistry and Molecular Cell Biology, Medical School, RWTH Aachen University, 52074, Aachen, Germany.
Sci Rep. 2020 Nov 9;10(1):19301. doi: 10.1038/s41598-020-76192-1.
Ciliopathies are clinical disorders of the primary cilium with widely recognised phenotypic and genetic heterogeneity. Here, we found impaired ciliogenesis in fibroblasts derived from individuals with fetal akinesia deformation sequence (FADS), a broad spectrum of neuromuscular disorders arising from compromised foetal movement. We show that cells derived from FADS individuals have shorter and less primary cilia (PC), in association with alterations in post-translational modifications in α-tubulin. Similarly, siRNA-mediated depletion of two known FADS proteins, the scaffold protein rapsyn and the nucleoporin NUP88, resulted in defective PC formation. Consistent with a role in ciliogenesis, rapsyn and NUP88 localised to centrosomes and PC. Furthermore, proximity-ligation assays confirm the respective vicinity of rapsyn and NUP88 to γ-tubulin. Proximity-ligation assays moreover show that rapsyn and NUP88 are adjacent to each other and that the rapsyn-NUP88 interface is perturbed in the examined FADS cells. We suggest that the perturbed rapsyn-NUP88 interface leads to defects in PC formation and that defective ciliogenesis contributes to the pleiotropic defects seen in FADS.
纤毛病是一种原发性纤毛的临床功能障碍，具有广泛公认的表型和遗传异质性。在这里，我们发现胎儿运动障碍序列（FADS）个体来源的成纤维细胞中纤毛发生受损，FADS 是一种广泛的神经肌肉疾病，源于胎儿运动受损。我们表明，源自 FADS 个体的细胞具有较短和较少的初级纤毛（PC），这与α-微管蛋白翻译后修饰的改变有关。同样，通过 siRNA 介导的两种已知 FADS 蛋白，支架蛋白 rapsyn 和核孔蛋白 NUP88 的耗竭，导致 PC 形成缺陷。与纤毛发生作用一致，rapsyn 和 NUP88 定位于中心体和 PC。此外，接近连接测定证实了 rapsyn 和γ-微管蛋白之间的相应临近性。接近连接测定还表明，rapsyn 和 NUP88 彼此相邻，并且在所检查的 FADS 细胞中，rapsyn-NUP88 界面受到干扰。我们认为，扰动的 rapsyn-NUP88 界面导致 PC 形成缺陷，而纤毛发生缺陷导致 FADS 中所见的多效性缺陷。
