Altered cell cycle distribution, hyperplasia, and inhibited differentiation in arabidopsis caused by the D-type cyclin CYCD3
Altered cell cycle distribution, hyperplasia, and inhibited differentiation in arabidopsis caused by the D-type cyclin CYCD3
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DOI：
10.1105/tpc.004838
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发表时间：
2003-01-01
期刊：
影响因子：
11.6
通讯作者：
Murray, JAH
中科院分区：
文献类型：
--
作者：
Dewitte, W;Riou-Khamlichi, C;Murray, JAH
CYCD 3; 1在拟南芥中的表达与增殖组织如分生组织和发育中的叶有关，但与分化的组织无关。CYCD 3; 1的组成性过表达增加了CYCD 3; 1相关激酶的活性，并降低了细胞周期G1期细胞的比例。此外，CYCD 3; 1过表达导致发育的显著改变。过度表达植物的叶结构发生根本性改变，不能发育出明显的海绵层和栅栏叶肉层。与此相关，我们观察到叶细胞的过度增殖，特别是，表皮由大量的小，不完全分化的多边形细胞。细胞核内复制是分化细胞退出有丝分裂细胞周期的标志，在CYCD 3; 1过表达植物中受到强烈抑制。转录分析揭示了激活后CYCD 3; 1过表达或随后的细胞周期激活推定的代偿机制。这些结果表明，在G1期细胞周期退出所需的正常细胞分化过程中，在植物发育和建议的关键作用CYCD3在开关从细胞增殖分化的最后阶段。
CYCD3;1 expression in Arabidopsis is associated with proliferating tissues such as meristems and developing leaves but not with differentiated tissues. Constitutive overexpression of CYCD3;1 increases CYCD3;1-associated kinase activity and reduces the proportion of cells in the G1-phase of the cell cycle. Moreover, CYCD3;1 overexpression leads to striking alterations in development. Leaf architecture in overexpressing plants is altered radically, with a failure to develop distinct spongy and palisade mesophyll layers. Associated with this, we observe hyperproliferation of leaf cells; in particular, the epidermis consists of large numbers of small, incompletely differentiated polygonal cells. Endoreduplication, a marker for differentiated cells that have exited from the mitotic cell cycle, is inhibited strongly in CYCD3;1 overexpressing plants. Transcript analysis reveals an activation of putative compensatory mechanisms upon CYCD3;1 overexpression or subsequent cell cycle activation. These results demonstrate that cell cycle exit in the G1-phase is required for normal cellular differentiation processes during plant development and suggest a critical role for CYCD3 in the switch from cell proliferation to the final stages of differentiation.