Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Precursory Research for Embryonic Science and Technology (PRESTO), Japan Science and Technology Agency, 4-1-8, Honcho, Kawaguchi, Saitama 332-0012, Japan.
Int J Mol Sci. 2017 Oct 17;18(10):2161. doi: 10.3390/ijms18102161.
The number, size and shape of polymorphic plant mitochondria are determined at least partially by mitochondrial fission. Arabidopsis mitochondria divide through the actions of a dynamin-related protein, DRP3A. Another plant-specific factor, ELM1, was previously shown to localize DRP3A to mitochondrial fission sites. Here, we report that mitochondrial fission is not completely blocked in the Arabidopsis mutant and that it is strongly manifested in response to cold treatment. Arabidopsis has an paralogue () that seems to have only a limited role in mitochondrial fission in the mutant. Interestingly, cold-induced mitochondrial fragmentation was also observed in the wild-type, but not in a mutant, suggesting that cold-induced transient mitochondrial fragmentation requires DRP3A but not ELM1 or ELM2. DRP3A: GFP localized from the cytosol to mitochondrial fission sites without ELM1 after cold treatment. Together, these results suggest that Arabidopsis has a novel, cold-induced type of mitochondrial fission in which DRP3A localizes to mitochondrial fission sites without the involvement of ELM1 or ELM2.
多态植物线粒体的数量、大小和形状至少部分由线粒体分裂决定。拟南芥线粒体通过一种与 dynamin 相关的蛋白（DRP3A）的作用进行分裂。另一种植物特异性因子 ELM1 以前被证明将 DRP3A 定位到线粒体分裂部位。在这里，我们报告说，拟南芥 突变体中的线粒体分裂并没有完全被阻断，并且在冷处理时强烈表现出来。拟南芥有一个 等位基因（），它似乎在 突变体中的线粒体分裂中只起有限的作用。有趣的是，在野生型中也观察到了冷诱导的线粒体片段化，但在 突变体中没有，这表明冷诱导的瞬时线粒体片段化需要 DRP3A，但不需要 ELM1 或 ELM2。在冷处理后，DRP3A：GFP 从细胞质定位到线粒体分裂部位，而没有 ELM1。这些结果表明，拟南芥存在一种新的、冷诱导的线粒体分裂类型，其中 DRP3A 在不涉及 ELM1 或 ELM2 的情况下定位于线粒体分裂部位。
