The Arabidopsis SMO2, a homologue of yeast TRM112, modulates progression of cell division during organ growth
The Arabidopsis SMO2, a homologue of yeast TRM112, modulates progression of cell division during organ growth
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DOI：
10.1111/j.1365-313x.2009.04085.x
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发表时间：
2010-02-01
期刊：
影响因子：
7.2
通讯作者：
Hu, Yuxin
中科院分区：
文献类型：
--
作者：
Hu, Zhubing;Qin, Zhixiang;Hu, Yuxin
在包括植物在内的多细胞生物中，细胞增殖被整合到发育过程中，细胞分裂的调控对植物的生长和发育具有至关重要的作用。在这里，我们报告了一个拟南芥小器官2(SMO2)基因的鉴定，该基因在器官生长过程中调节细胞分裂的进程。Smo2基因敲除突变体表现出气生器官的尺寸减小，根变短，这是由于这些器官中的细胞数量减少所致。进一步的分析表明，SMO2的干扰不会改变发育的时间，但会降低叶和根生长过程中细胞的产生速度。此外，在器官发生过程中，Smo2植物表现出细胞周期相关基因的结构性激活和细胞过度表达CyCB1；1：β-葡萄糖醛酸酶(CyCB1；1：GUS)，这表明Smo2在细胞周期的G(2)-M期进程中存在缺陷。SMO2编码酵母TRM112的功能同源物，TRM112是一种参与一些细胞事件的多功能成分，包括tRNA和蛋白质甲基化。此外，SMO2的突变似乎不会影响拟南芥叶片细胞的内复制。综上所述，我们推测拟南芥SMO2是一个保守的酵母TRM112同源物，SMO2介导的细胞事件是植物生长发育中细胞分裂正常进行所必需的。
Cell proliferation is integrated into developmental progression in multicellular organisms, including plants, and the regulation of cell division is of pivotal importance for plant growth and development. Here, we report the identification of an Arabidopsis SMALL ORGAN 2 (SMO2) gene that functions in regulation of the progression of cell division during organ growth. The smo2 knockout mutant displays reduced size of aerial organs and shortened roots, due to the decreased number of cells in these organs. Further analyses reveal that disruption of SMO2 does not alter the developmental timing but reduces the rate of cell production during leaf and root growth. Moreover, smo2 plants exhibit a constitutive activation of cell cycle-related genes and over-accumulation of cells expressing CYCB1;1:beta-glucuronidase (CYCB1;1:GUS) during organogenesis, suggesting that smo2 has a defect in G(2)-M phase progression in the cell cycle. SMO2 encodes a functional homologue of yeast TRM112, a plurifunctional component involved in a few cellular events, including tRNA and protein methylation. In addition, the mutation of SMO2 does not appear to affect endoreduplication in Arabidopsis leaf cells. Taken together we postulate that Arabidopsis SMO2 is a conserved yeast TRM112 homologue and SMO2-mediated cellular events are required for proper progression of cell division in plant growth and development.