Perturbation of auxin homeostasis caused by mitochondrial FtSH4 gene-mediated peroxidase accumulation regulates arabidopsis architecture.
Perturbation of auxin homeostasis caused by mitochondrial FtSH4 gene-mediated peroxidase accumulation regulates arabidopsis architecture.
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DOI：
10.1093/mp/ssu006
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发表时间：
2014-05
期刊：
影响因子：
27.5
通讯作者：
Shengchun Zhang;Juelin Wu;Dongke Yuan;Daowei Zhang;Zhigang Huang;Langtao Xiao;Chengwei Yang
中科院分区：
文献类型：
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作者：
Shengchun Zhang;Juelin Wu;Dongke Yuan;Daowei Zhang;Zhigang Huang;Langtao Xiao;Chengwei Yang
活性氧和生长素在调节植物发育和形态发生变化的网络中发挥着重要作用。然而，人们对它们之间相互作用的分子机制知之甚少。本研究分离了 mas（更多腋芽）突变体，该突变体被鉴定为线粒体 AAA 蛋白酶 AtFtSH4 的等位基因，并表征了 FtSH4 基因通过介导过氧化氢 (H2O2) 和生长素稳态之间的过氧化物酶依赖性相互作用来调节植物发育的功能。在 mas（更名为 ftsh4-4）突变体中观察到的侏儒症和腋枝增加的表型是由于 IAA 浓度降低所致。 ftsh4-4 植物中多个生长素信号基因（包括 IAA1、IAA2 和 IAA3）以及多个生长素结合和转运基因的表达水平显着下降。然而，ftsh4-4 植物中的 H2O2 和过氧化物酶水平（也具有 IAA 氧化酶活性）显着升高。 ftsh4-4表型可以通过表达iaaM基因或敲除过氧化物酶基因PRX34和PRX33来逆转。两种方法都可以增加 ftsh4-4 突变体中的生长素水平。总而言之，这些结果为线粒体 ATP 依赖性蛋白酶、H2O2 和生长素稳态之间的相互作用调节植物生长和发育提供了直接的分子和遗传证据。
Reactive oxygen species and auxin play important roles in the networks that regulate plant development and morphogenetic changes. However, the molecular mechanisms underlying the interactions between them are poorly understood. This study isolated a mas (More Axillary Shoots) mutant, which was identified as an allele of the mitochondrial AAA-protease AtFtSH4, and characterized the function of the FtSH4 gene in regulating plant development by mediating the peroxidase-dependent interplay between hydrogen peroxide (H2O2) and auxin homeostasis. The phenotypes of dwarfism and increased axillary branches observed in the mas (renamed as ftsh4-4) mutant result from a decrease in the IAA concentration. The expression levels of several auxin signaling genes, including IAA1, IAA2, and IAA3, as well as several auxin binding and transport genes, decreased significantly in ftsh4-4 plants. However, the H2O2 and peroxidases levels, which also have IAA oxidase activity, were significantly elevated in ftsh4-4 plants. The ftsh4-4 phenotypes could be reversed by expressing the iaaM gene or by knocking down the peroxidase genes PRX34 and PRX33. Both approaches can increase auxin levels in the ftsh4-4 mutant. Taken together, these results provided direct molecular and genetic evidence for the interaction between mitochondrial ATP-dependent protease, H2O2, and auxin homeostasis to regulate plant growth and development.