The SWI/SNF subunit SWI3B regulates IAMT1 expression via chromatin remodeling in Arabidopsis leaf development
The SWI/SNF subunit SWI3B regulates IAMT1 expression via chromatin remodeling in Arabidopsis leaf development
复制标题
SWI/SNF 亚基 SWI3B 通过拟南芥叶片发育中染色质重塑调节 IAMT1 表达
DOI：
10.1016/j.plantsci.2018.03.021
复制
发表时间：
2018-06-01
期刊：
影响因子：
5.2
通讯作者：
Yang, Chengwei
中科院分区：
文献类型：
--
作者：
Han, Wenxing;Han, Danlu;Yang, Chengwei
SWI/SNF 复合物对于不同物种的各种生物过程中的染色质重塑至关重要，但其成分在植物发育中的独特功能仍不清楚。在这里，我们通过 RNA 干扰揭示了拟南芥 SWI/SNF 复合物的亚基 SWI3B 的作用。 SWI3 B 的敲低导致叶子向上卷曲的表型。进一步研究表明，编码参与生长素代谢的酶 IAA 羧甲基转移酶 1 (IAMT1) 的 RNA 水平在敲低 (SW13B-RNAi) 植物中显着升高。此外，IAMT1 的激活产生了与 SWI3B-RNAi 系相似的卷叶表型。数据库分析表明IAMT的最后一个内含子含有聚合酶V（Pol V）稳定核小体的位点，该位点可能与SWI3B有关。微球菌核酸酶 (MNase) 消化测定的数据表明，SWI3B-RNAi 植物叶片中该位点周围的核小体占用量下调。此外，在 SWI3B-RNAi 背景下敲低 IAMT1 抑制了异常的叶片发育。因此，SWI3B 介导的染色质重塑对于调节叶片发育中 IAMT1 的表达至关重要。
The SWI/SNF complex is crucial to chromatin remodeling in various biological processes in different species, but the distinct functions of its components in plant development remain unclear. Here we uncovered the role of SWI3B, a subunit of the Arabidopsis thaliana SWI/SNF complex, via RNA interference. Knockdown of SWI3 B resulted in an upward-curling leaf phenotype. Further investigation showed that the RNA level of IAA carboxyl methyltransferase 1 (IAMT1), encoding an enzyme involved in auxin metabolism, was dramatically elevated in the knockdown (SW13B-RNAi) plants. In addition, activation of IAMT1 produced a leaf-curling phenotype similar to that of the SWI3B-RNAi lines. Database analysis suggested that the last intron of IAMT contains a site of polymerase V (Pol V) stabilized nucleosome, which may be associated with SWI3B. Data from a micrococcal nuclease (MNase) digestion assay showed that nucleosome occupancy around this site was downregulated in the leaves of SWI3B-RNAi plants. In addition, knockdown of IAMT1 in the SWI3B-RNAi background repressed the abnormal leaf development. Thus, SWI3B-mediated chromatin remodeling is critical in regulating the expression of IAMT1 in leaf development.