Graduate School of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara, 630-0192, Japan.
Department of Biological Sciences, Faculty of Science, Hokkaido University, Kita-ku, Sapporo 060-0810, Japan.
J Exp Bot. 2015 Feb;66(4):1055-63. doi: 10.1093/jxb/erv028. Epub 2015 Jan 29.
Leaves are ideal model systems to study the organ size regulation of multicellular plants. Leaf cell number and cell size are determinant factors of leaf size which is controlled through cell proliferation and post-mitotic cell expansion, respectively. To achieve a proper leaf size, cell proliferation and post-mitotic cell expansion should be co-ordinated during leaf morphogenesis. Compensation, which is enhanced post-mitotic cell expansion associated with a decrease in cell number during lateral organ development, is suggestive of such co-ordination. Genetic and kinematic studies revealed at least three classes of modes of compensation, indicating that compensation is a heterogeneous phenomenon. Recent studies have increased our understanding about the molecular basis of compensation by identifying the causal genes of each compensation-exhibiting mutant. Furthermore, analyses using chimeric leaves revealed that a type of compensated cell expansion requires cell-to-cell communication. Information from recent advances in molecular and genetic studies on compensation has been integrated here and its role in organ size regulation is discussed.
叶片是研究多细胞植物器官大小调控的理想模式系统。叶片细胞数量和细胞大小是决定叶片大小的决定因素，分别通过细胞增殖和有丝分裂后细胞扩张来控制。为了获得适当的叶片大小，细胞增殖和有丝分裂后细胞扩张应在叶片形态发生过程中协调进行。补偿作用，即在侧生器官发育过程中细胞数量减少的同时增强有丝分裂后细胞扩张，提示了这种协调作用。遗传和运动学研究揭示了至少三种补偿模式的类别，表明补偿是一种异质现象。最近的研究通过鉴定每个表现出补偿的突变体的因果基因，增加了我们对补偿分子基础的理解。此外，使用嵌合叶片进行的分析表明，一种补偿性细胞扩张需要细胞间通讯。这里整合了补偿的分子和遗传研究的最新进展所提供的信息，并讨论了其在器官大小调控中的作用。
