Department of Anatomy and Developmental Biology, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kyoto 602-8566, Japan.
Dev Biol. 2010 Nov 1;347(1):62-70. doi: 10.1016/j.ydbio.2010.08.008. Epub 2010 Aug 13.
Cilia and flagella are highly conserved organelles that have diverse motility and sensory functions. Motility defects in cilia and flagella result in primary ciliary dyskinesia (PCD). We isolated a novel medaka PCD mutant, jaodori (joi). Positional cloning showed that axonemal dynein intermediate chain 2 (dnai2) is responsible for joi. The joi mutation was caused by genomic insertion of the medaka transposon, Tol1. In the joi mutant, cilia in Kupffer's vesicle (KV), an organ functionally equivalent to the mouse node in terms of left-right (LR) specification, are generated but their motility is disrupted, resulting in a LR defect. Ultrastructural analysis revealed severe reduction in the outer dynein arms in KV cilia of joi mutants. We also found the other dnai2 gene in the medaka genome. These two dnai2 genes function either redundantly or distinctly in tissues possessing motile cilia.
纤毛和鞭毛是高度保守的细胞器，具有多种运动和感觉功能。纤毛和鞭毛的运动缺陷导致原发性纤毛运动障碍（PCD）。我们分离出一种新型的斑马鱼 PCD 突变体，jaodori（joi）。定位克隆表明轴丝中间链 2（dnai2）是 joi 的原因。joi 突变是由斑马鱼转座子 Tol1 的基因组插入引起的。在 joi 突变体中，Kupffer 囊泡（KV）中的纤毛产生，但它们的运动被破坏，导致左右（LR）缺陷。超微结构分析显示，joi 突变体 KV 纤毛的外动力臂严重减少。我们还在斑马鱼基因组中发现了另一个 dnai2 基因。这两个 dnai2 基因在具有运动纤毛的组织中要么冗余，要么功能不同。
