LIRANS, Institute of Research in the Applied Natural Sciences, University of Bedfordshire, Luton, Bedfordshire, UK.
Theriogenology. 2011 Oct 1;76(6):1110-9. doi: 10.1016/j.theriogenology.2011.05.018. Epub 2011 Jul 12.
The distributional arrangement of mitochondria in the granulosa cells surrounding stage III zebrafish oocyte has been reported as a contiguous aggregation of mitochondria at the margin of the each granulosa cell. The aim of the present study was to further investigate the mitochondrial distribution in the granulosa cell layer in stage III ovarian follicles and the interaction between mitochondria and cytoskeleton elements actin and tubulin. To determine mitochondrial distribution/transport, immunocytochemistry analysis of tubulin and mitochondrial COX-I was carried out along with phalloidin staining of polymerised F-actin. The follicles were also exposed to a range of conditions that are known to affect mitochondria and the cytoskeleton proteins actin and tubulin. The mitochondrial inhibitor FCCP, the anti-mitotic drug nocodazole, and actin polymerisation inhibitor cytochalasin B were used. Levels of ATP, mtDNA copy number, and viability assessed by Trypan blue were also studied after exposure to inhibitors in order to determine the relationship between mitochondrial distribution/activity and ATP production. F-actin showed a hexagonal-polygonal distribution surrounding the mitochondria in granulosa cells, with the F-actin network adjacent to the plasma membrane of each granulosa cell. Tubulin structure presented a less organised distribution than F-actin, it was sparse in the cytosol. Interaction between mitochondria and tubulin was found indicating that mitochondria and tubulin are colocalised in zebrafish ovarian follicles. The exposure of ovarian follicles to inhibitors induced the loss of mitochondrial structural integrity showing that mitochondria distribution in granulosa cells of stage III zebrafish ovarian follicles is determined by the microtubules network.
已报道在斑马鱼 III 期卵母细胞周围的颗粒细胞中，线粒体呈连续聚集分布在每个颗粒细胞的边缘。本研究旨在进一步研究 III 期卵巢滤泡中颗粒细胞层中的线粒体分布以及线粒体与细胞骨架元件肌动蛋白和微管蛋白之间的相互作用。为了确定线粒体的分布/运输，对微管蛋白和线粒体 COX-I 进行了免疫细胞化学分析，并对聚合的 F-肌动蛋白进行了鬼笔环肽染色。还将卵泡暴露于已知影响线粒体和细胞骨架蛋白肌动蛋白和微管蛋白的一系列条件下。使用了线粒体抑制剂 FCCP、抗有丝分裂药物诺考达唑和肌动蛋白聚合抑制剂细胞松弛素 B。还研究了暴露于抑制剂后 ATP 水平、mtDNA 拷贝数和通过台盼蓝评估的活力，以确定线粒体分布/活性与 ATP 产生之间的关系。在颗粒细胞中，F-肌动蛋白围绕线粒体呈六边形多角形分布，F-肌动蛋白网络与每个颗粒细胞的质膜相邻。微管蛋白结构的分布不如 F-肌动蛋白有序，在细胞质中稀疏。发现线粒体与微管蛋白之间存在相互作用，表明线粒体和微管蛋白在斑马鱼卵巢滤泡中共定位。卵巢滤泡暴露于抑制剂会导致线粒体结构完整性丧失，表明 III 期斑马鱼卵巢滤泡中颗粒细胞中的线粒体分布由微管网络决定。
