Mutation in the human MPV17 gene or the functional yeast orthologue SYM1 result in mitochondrial DNA depletion. MPV17 homologs are also found in plants including Arabidopsis, but the function of these genes remain unclear. Arabidopsis genome contains 10 MPV17 homologs. Among these, the AtMPV17 protein was localized in mitochondria as MPV17 and SYM1. The yeast sym1 knock out mutant cannot grow on ethanol-containing medium at 37 °C. AtMPV17 complements the ethanol growth defection of sym1 yeast MPV17 ortholog cells at 37 °C, suggesting that AtMPV17 is a functional ortholog of SYM1. AtMPV17 knock out mutant, atmpv17 show similar growth and seed development to those of the wild-type plant on normal growth condition. However, atmpv17 mutant is more sensitive to ABA and mannitol during germination and seedling growth than wild type plants. Growth retardation of the atmpv17 knock out mutant on medium containing ABA and mannitol is complemented by AtMPV17 overexpression. These results suggest that the AtMPV17 contributes to osmotic stress tolerance in plants.

中文翻译：

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拟南芥AtMPV17是小鼠MPV17的同源物，可增强渗透压耐受性。

人MPV17基因或功能性酵母直向同源基因SYM1中的突变导致线粒体DNA耗竭。在包括拟南芥在内的植物中也发现了MPV17同源物，但这些基因的功能仍不清楚。拟南芥基因组包含10个MPV17同源物。其中，AtMPV17蛋白位于线粒体中，称为MPV17和SYM1。酵母sym1敲除突变体不能在37°C的含乙醇培养基上生长。AtMPV17在37°C时补充了sym1酵母MPV17直系同源细胞的乙醇生长缺陷，表明AtMPV17是SYM1的功能直系同源物。AtMPV17敲除突变体，atmpv17在正常生长条件下显示出与野生型植物相似的生长和种子发育。但是，与野生型植物相比，atmpv17突变体在发芽和幼苗生长期间对ABA和甘露醇的敏感性更高。Atmpv17敲除突变体在含有ABA和甘露醇的培养基上的生长迟缓由AtMPV17过表达补充。这些结果表明AtMPV17有助于植物的渗透胁迫耐受性。