Murley Andrew, Lackner Laura L, Osman Christof, West Matthew, Voeltz Gia K, Walter Peter, Nunnari Jodi
Department of Molecular and Cellular Biology , University of California, Davis , Davis , United States.
Elife. 2013 May 14;2:e00422. doi: 10.7554/eLife.00422.
Mitochondrial division is important for mitochondrial distribution and function. Recent data have demonstrated that ER-mitochondria contacts mark mitochondrial division sites, but the molecular basis and functions of these contacts are not understood. Here we show that in yeast, the ER-mitochondria tethering complex, ERMES, and the highly conserved Miro GTPase, Gem1, are spatially and functionally linked to ER-associated mitochondrial division. Gem1 acts as a negative regulator of ER-mitochondria contacts, an activity required for the spatial resolution and distribution of newly generated mitochondrial tips following division. Previous data have demonstrated that ERMES localizes with a subset of actively replicating mitochondrial nucleoids. We show that mitochondrial division is spatially linked to nucleoids and that a majority of these nucleoids segregate prior to division, resulting in their distribution into newly generated tips in the mitochondrial network. Thus, we postulate that ER-associated division serves to link the distribution of mitochondria and mitochondrial nucleoids in cells. DOI:http://dx.doi.org/10.7554/eLife.00422.001.
线粒体分裂对于线粒体的分布和功能至关重要。最近的数据表明,内质网-线粒体接触点标记了线粒体的分裂位点,但这些接触点的分子基础和功能尚不清楚。在这里,我们表明在酵母中,内质网-线粒体连接复合物ERMES和高度保守的米罗GTP酶Gem1在空间和功能上与内质网相关的线粒体分裂相联系。Gem1作为内质网-线粒体接触的负调节因子,这一活性是分裂后新生成的线粒体末端的空间分辨率和分布所必需的。先前的数据表明,ERMES定位于一部分活跃复制的线粒体核仁。我们表明线粒体分裂在空间上与核仁相联系,并且这些核仁中的大多数在分裂之前就发生了分离,从而导致它们分布到线粒体网络中的新生成的末端。因此,我们推测内质网相关的分裂有助于将细胞中线粒体和线粒体核仁的分布联系起来。DOI:http://dx.doi.org/10.7554/eLife.00422.001