Xu Duorong, Leister Dario, Kleine Tatjana
Plant Molecular Biology, Department Biology I, Ludwig-Maximilians-Universität MünchenPlanegg-Martinsried, Germany.
Front Plant Sci. 2017 Jul 14;8:1213. doi: 10.3389/fpls.2017.01213. eCollection 2017.
Plastid gene expression (PGE) is crucial for plant development and acclimation to various environmental stress conditions. Members of the "mitochondrial transcription termination factor" (mTERF) family, which are present in both metazoans and plants, are involved in organellar gene expression. contains 35 mTERF proteins, of which mTERF10, mTERF11, and mTERF12 were previously assigned to the "chloroplast-associated" group. Here, we show that all three are localized to chloroplast nucleoids, which are associated with PGE. Knock-down of , or has no overt phenotypic effect under normal growth conditions. However, analysis of , -, and - expression levels points to a possible involvement of mTERF10 and mTERF11 in responses to abiotic stress. Exposing mutant lines for 7 days to moderate heat (30°C) or light stress (400 μmol photons m s) fails to induce a phenotype in mutant lines. However, growth on MS medium supplemented with NaCl reveals that overexpression of results in higher salt tolerance. Conversely, mutants are hypersensitive to salt stress, while plants that modestly overexpress are markedly less susceptible. Furthermore, overexpression leads to enhanced germination and growth on MS medium supplemented with ABA. These findings point to an involvement of mTERF10 in salt tolerance, possibly through an ABA-mediated mechanism. Thus, characterization of an increasing number of plant mTERF proteins reveals their roles in the response, tolerance and acclimation to different abiotic stresses.
质体基因表达（PGE）对于植物发育以及适应各种环境胁迫条件至关重要。“线粒体转录终止因子”（mTERF）家族的成员存在于后生动物和植物中，参与细胞器基因表达。[具体植物名称]包含35种mTERF蛋白，其中mTERF10、mTERF11和mTERF12先前被归为“叶绿体相关”组。在这里，我们表明这三种蛋白都定位于与PGE相关的叶绿体类核中。在正常生长条件下，敲低[具体基因名称]、[具体基因名称]或[具体基因名称]没有明显的表型效应。然而，对[具体基因名称]、[具体基因名称]和[具体基因名称]表达水平的分析表明，mTERF10和mTERF11可能参与非生物胁迫响应。将突变株暴露于中度热胁迫（30°C）或光胁迫（400 μmol光子·m⁻²·s⁻¹）7天，[具体突变株名称]突变株未出现表型。然而，在添加NaCl的MS培养基上生长表明，[具体基因名称]的过表达导致更高的耐盐性。相反，[具体突变株名称]突变体对盐胁迫高度敏感，而适度过表达[具体基因名称]的植物明显更不易感。此外，[具体基因名称]的过表达导致在添加ABA的MS培养基上萌发和生长增强。这些发现表明mTERF10可能通过ABA介导的机制参与耐盐性。因此，对越来越多植物mTERF蛋白的表征揭示了它们在对不同非生物胁迫的响应、耐受和适应中的作用。
