Mitochondrial Fission Complex Is Required for Long-Term Heat Tolerance of Arabidopsis
Mitochondrial Fission Complex Is Required for Long-Term Heat Tolerance of Arabidopsis
复制标题
拟南芥的长期耐热性需要线粒体裂变复合体
DOI：
10.1093/pcp/pcab171
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发表时间：
2022
影响因子：
4.9
通讯作者：
Teruaki Taji
中科院分区：
文献类型：
--
作者：
Ryo Tsukimoto;Kazuho Isono;Takuma Kajino;Satoshi Iuchi;Akihisa Shinozawa;Izumi Yotsui;Yoichi Sakata;Teruaki Taji
植物经常不仅暴露在短期(S)热胁迫下，而且还暴露在连续几天的长期(L)热胁迫下。目前已鉴定出一些L耐热性缺失的拟南芥突变体，但与S耐热性相关的分子机制尚不清楚。为了阐明这一机制，我们从L耐热Col-0的种子中分离到了一个新的对长期高温敏感的突变体sloh5。该突变体对L高温敏感，对S高温、渗透压、盐激和氧化胁迫不敏感。原因基因SLOH5与细长线粒体1(ELM1)相同，ELM1与动力蛋白相关蛋白DRP3A和DRP3B一起在线粒体分裂中发挥重要作用。ELM1、DRP3A和DRP3B的转录水平在L热应激下呈时间依赖性升高，并且drp3a、drp3b双突变体对L热应激敏感。该突变体含有大量拉长的线粒体。L-热应激导致线粒体功能障碍和细胞死亡。此外，用线粒体肌球蛋白ATPase抑制剂处理的WT植株对L热胁迫高度敏感。这些结果表明线粒体的分裂和功能在拟南芥的L耐热性中起着重要的作用。
Plants are often exposed not only to short-term (S) heat stress but also to long-term (L) heat stress over several consecutive days. A few Arabidopsis mutants defective in L-heat tolerance have been identified, but the molecular mechanisms involved are less well understood than those involved in S-heat tolerance. To elucidate the mechanisms, we isolated the newsensitive tolong-termheat5(sloh5) mutant from EMS-mutagenized seeds of L-heat-tolerant Col-0. Thesloh5mutant was hypersensitive to L-heat but not to S-heat, osmo-shock, salt-shock or oxidative stress. The causal gene,SLOH5, is identical toelongatedmitochondria1(ELM1), which plays an important role in mitochondrial fission in conjunction with dynamin-related proteins DRP3A and DRP3B. Transcript levels ofELM1, DRP3AandDRP3Bwere time-dependently increased by L-heat stress, anddrp3a drp3bdouble mutants were hypersensitive to L-heat stress. Thesloh5mutant contained massively elongated mitochondria. L-heat stress caused mitochondrial dysfunction and cell death insloh5. Furthermore, WT plants treated with a mitochondrial myosin ATPase inhibitor were hypersensitive to L-heat stress. These findings suggest that mitochondrial fission and function are important in L-heat tolerance of Arabidopsis.