MORF-RELATED GENE702, a Reader Protein of Trimethylated Histone H3 Lysine 4 and Histone H3 Lysine 36, Is Involved in Brassinosteroid-Regulated Growth and Flowering Time Control in Rice
MORF-RELATED GENE702, a Reader Protein of Trimethylated Histone H3 Lysine 4 and Histone H3 Lysine 36, Is Involved in Brassinosteroid-Regulated Growth and Flowering Time Control in Rice
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MORF 相关基因 702 是三甲基化组蛋白 H3 赖氨酸 4 和组蛋白 H3 赖氨酸 36 的读取蛋白，参与油菜素类固醇调节的水稻生长和开花时间控制
DOI：
10.1104/pp.114.255737
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发表时间：
2015-08-01
期刊：
影响因子：
7.4
通讯作者：
Dong, Aiwu
中科院分区：
文献类型：
--
作者：
Jin, Jing;Shi, Jinlei;Dong, Aiwu
组蛋白H3赖氨酸36（H3K36）的甲基化在油菜素类固醇（BR）相关过程中起关键作用，并参与控制水稻（Oryza sativa）的开花时间。虽然已经描述了催化这种甲基化反应的酶，但对破译水稻中H3K36甲基化信息的识别机制知之甚少。在这项研究中，生物化学特性表明，MORF相关基因702（MRG 702）在体外与三甲基化的H3K4和H3K36（H3K4me3和H3K36me3）结合。与水稻H3K36甲基转移酶基因SET DOMAIN GROUP725（SDG725）的功能缺失突变体相似，MRG 702敲除突变体表现出典型的BR缺陷突变体和晚花表型。基因转录分析表明，MRG 702敲低导致BR相关基因的下调，包括DWARF11，油菜甾醇不敏感1，油菜甾醇上调1，和几个开花基因，包括早抽穗日期1（Ehd1），Ehd2，Ehd3，OsMADS 50，抽穗日期3a，和水稻开花位点T1。结合分析显示，MRG 702直接结合靶基因座处的染色质。这种结合依赖于由SDG 725介导的三甲基化H3K36的水平。总之，我们的研究结果表明，MRG 702作为H3K4me3和H3K36me3的阅读器蛋白，并破译了SDG 725设置的H3K36甲基化信息。因此，MRG 702在BR途径中的作用和在控制水稻开花时间中的作用是作为解读甲基化信息的阅读蛋白。
The methylation of histone H3 lysine 36 (H3K36) plays critical roles in brassinosteroid (BR)-related processes and is involved in controlling flowering time in rice (Oryza sativa). Although enzymes that catalyze this methylation reaction have been described, little is known about the recognition mechanisms to decipher H3K36 methylation information in rice. In this study, biochemical characterizations showed that MORF-RELATED GENE702 (MRG702) binds to trimethylated H3K4 and H3K36 (H3K4me3 and H3K36me3) in vitro. Similar to the loss-of-function mutants of the rice H3K36 methyltransferase gene SET DOMAIN GROUP725 (SDG725), the MRG702 knockdown mutants displayed typical BR-deficient mutant and late-flowering phenotypes. Gene transcription analyses showed that MRG702 knockdown resulted in the down-regulation of BR-related genes, including DWARF11, BRASSINOSTEROD INSENSITIVE1, and BRASSINOSTEROID UPREGULATED1, and several flowering genes, including Early heading date1 (Ehd1), Ehd2, Ehd3, OsMADS50, Heading date 3a, and RICE FLOWERING LOCUS T1. A binding analysis showed that MRG702 directly binds to the chromatin at target gene loci. This binding is dependent on the level of trimethylated H3K36, which is mediated by SDG725. Together, our results demonstrate that MRG702 acts as a reader protein of H3K4me3 and H3K36me3 and deciphers the H3K36 methylation information set by SDG725. Therefore, the role of MRG702 in the BR pathway and in controlling flowering time in rice is to function as a reader protein to decipher methylation information.