Zebrafish Ciliopathy Screen Plus Human Mutational Analysis Identifies C21orf59 and CCDC65 Defects as Causing Primary Ciliary Dyskinesia
Zebrafish Ciliopathy Screen Plus Human Mutational Analysis Identifies C21orf59 and CCDC65 Defects as Causing Primary Ciliary Dyskinesia
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DOI：
10.1016/j.ajhg.2013.08.015
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发表时间：
2013-10-03
影响因子：
9.8
通讯作者：
Hildebrandt, Friedhelm
中科院分区：
文献类型：
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作者：
Austin-Tse, Christina;Halbritter, Jan;Hildebrandt, Friedhelm
原发性纤毛运动障碍（PCD）是由运动纤毛缺陷导致慢性气道感染、男性不育和体位异常引起的。多种致病性PCD突变仅占病例的65%，这表明许多纤毛功能所必需的基因仍有待发现。通过使用斑马鱼morpholino敲除PCD候选基因作为体内筛选平台，我们确定c21 orf 59，ccdc 65和c15 orf 26作为纤毛运动的关键。在斑马鱼和涡虫中，c21 orf 59和c15 orf 26敲低阻断了外动力蛋白臂组装，而cCDC 65敲低改变了纤毛搏动模式。衣原体的生化分析表明，C21 orf 59直系同源物FBB 18是一种鞭毛基质蛋白，当纤毛运动受损时特异性地积累。衣原体6突变体将CCDC 65/FAP 250鉴定为连接蛋白-动力蛋白调节复合物的重要组分。对295例PCD患者进行分析，发现4个家系存在C21 orf 59隐性截短突变，2个家系存在CCDC 65隐性截短突变。与斑马鱼和涡虫的研究结果相似，C21 orf 59的突变导致了外动力蛋白臂和内动力蛋白臂的丢失。我们的研究结果表征了两个与PCD引起的突变相关的基因，并阐明了运动纤毛功能的两种不同机制：C21 orf 59的动力蛋白臂组装和CCDC 65的连接蛋白-动力蛋白调节复合物组装。
Primary ciliary dyskinesia (PCD) is caused when defects of motile cilia lead to chronic airway infections, male infertility, and situs abnormalities. Multiple causative PCD mutations account for only 65% of cases, suggesting that many genes essential for cilia function remain to be discovered. By using zebrafish morpholino knockdown of PCD candidate genes as an in vivo screening platform, we identified c21orf59, ccdc65, and c15orf26 as critical for cilia motility. c21orf59 and c15orf26 knockdown in zebrafish and planaria blocked outer dynein arm assembly, and ccdc65 knockdown altered cilia beat pattern. Biochemical analysis in Chlamydomonas revealed that the C21orf59 ortholog FBB18 is a flagellar matrix protein that accumulates specifically when cilia motility is impaired. The Chlamydomonas ida6 mutant identifies CCDC65/FAP250 as an essential component of the nexin-dynein regulatory complex. Analysis of 295 individuals with PCD identified recessive truncating mutations of C21orf59 in four families and CCDC65 in two families. Similar to findings in zebrafish and planaria, mutations in C21orf59 caused loss of both outer and inner dynein arm components. Our results characterize two genes associated with PCD-causing mutations and elucidate two distinct mechanisms critical for motile cilia function: dynein arm assembly for C21orf59 and assembly of the nexin-dynein regulatory complex for CCDC65.