Reprogramming of H3K27me3 is critical for acquisition of pluripotency from cultured Arabidopsis tissues.
Reprogramming of H3K27me3 is critical for acquisition of pluripotency from cultured Arabidopsis tissues.
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H3K27me3 的重编程对于从培养的拟南芥组织中获得多能性至关重要
DOI：
10.1371/journal.pgen.1002911
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发表时间：
2012-08
期刊：
影响因子：
4.5
通讯作者：
Xu L
中科院分区：
文献类型：
--
作者：
He C;Chen X;Huang H;Xu L
在植物中，当在含有适当植物激素的培养基上培养时，多个离体组织能够形成多能细胞团，称为愈伤组织。最近的研究表明，愈伤组织类似于根尖分生组织，即使它是来自空中器官。这一发现提高了我们对植物细胞再生过程的理解；然而，引导不同组织类型的细胞形成愈伤组织的分子机制仍然是一个谜。本研究表明，组蛋白H3赖氨酸27三甲基化（H3K27me3）的全基因组重编程是叶片向愈伤组织转变的关键步骤。已知Polycomb suppression Complex 2 （PRC2）在H3K27me3的建立中起作用。通过分析不同组蛋白修饰途径对应的突变体愈伤组织形成，我们发现PRC2突变体curly leaf swinger （clfswwn）和embryonic flower2 （emf2）的叶片和/或子叶在愈伤组织形成方面存在缺陷。我们通过ChIP-chip实验在叶片和愈伤组织中鉴定了H3K27me3覆盖的位点，我们发现在愈伤组织中，H3K27me3水平首先在某些生长素途径基因上下降。在特定的叶片基因上，其水平升高，而在一些根调控基因上，其水平降低。H3K27me3水平的变化与相应基因的表达水平呈负相关。prc2介导的H3K27me3在叶片向愈伤组织转变中的一个可能作用可能与通过沉默叶片调控基因来消除叶片特征有关，因为大多数叶片优先表达的调控基因在clf雪的叶片外植体中不能被沉默。与叶片外植体相比，clf swwn和emf2的根外植体都能正常形成愈伤组织，这可能是因为根向愈伤组织的转变绕过了叶片基因的沉默过程。此外，我们的数据显示，prca2介导的H3K27me3和H3K27去甲基化在叶片向愈伤组织转变过程中平行作用于H3K27me3的重编程，这提示了植物细胞命运转变的一般机制。
In plants, multiple detached tissues are capable of forming a pluripotent cell mass, termed callus, when cultured on media containing appropriate plant hormones. Recent studies demonstrated that callus resembles the root-tip meristem, even if it is derived from aerial organs. This finding improves our understanding of the regeneration process of plant cells; however, the molecular mechanism that guides cells of different tissue types to form a callus still remains elusive. Here, we show that genome-wide reprogramming of histone H3 lysine 27 trimethylation (H3K27me3) is a critical step in the leaf-to-callus transition. The Polycomb Repressive Complex 2 (PRC2) is known to function in establishing H3K27me3. By analyzing callus formation of mutants corresponding to different histone modification pathways, we found that leaf blades and/or cotyledons of the PRC2 mutants curly leaf swinger (clf swn) and embryonic flower2 (emf2) were defective in callus formation. We identified the H3K27me3-covered loci in leaves and calli by a ChIP–chip assay, and we found that in the callus H3K27me3 levels decreased first at certain auxin-pathway genes. The levels were then increased at specific leaf genes but decreased at a number of root-regulatory genes. Changes in H3K27me3 levels were negatively correlated with expression levels of the corresponding genes. One possible role of PRC2-mediated H3K27me3 in the leaf-to-callus transition might relate to elimination of leaf features by silencing leaf-regulatory genes, as most leaf-preferentially expressed regulatory genes could not be silenced in the leaf explants of clf swn. In contrast to the leaf explants, the root explants of both clf swn and emf2 formed calli normally, possibly because the root-to-callus transition bypasses the leaf gene silencing process. Furthermore, our data show that PRC2-mediated H3K27me3 and H3K27 demethylation act in parallel in the reprogramming of H3K27me3 during the leaf-to-callus transition, suggesting a general mechanism for cell fate transition in plants.
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影响因子：
46.9
作者：
Ji, Hongkai;Jiang, Hui;Ma, Wenxiu;Johnson, David S.;Myers, Richard M.;Wong, Wing H.
通讯作者：
Wong, Wing H.
影响因子：
4.6
作者：
Chanvivattana, Y;Bishopp, A;Goodrich, J
通讯作者：
Goodrich, J
影响因子：
4.3
作者：
Che, Ping;Lall, Sonia;Howell, Stephen H.
通讯作者：
Howell, Stephen H.
影响因子：
7.2
作者：
Colón-Carmona, A;You, R;Doerner, P
通讯作者：
Doerner, P
影响因子：
3.7
作者：
GAMBORG, OL;MILLER, RA;OJIMA, K
通讯作者：
OJIMA, K