Arabidopsis TEBICHI, with helicase and DNA polymerase domains, is required for regulated cell division and differentiation in meristems
Arabidopsis TEBICHI, with helicase and DNA polymerase domains, is required for regulated cell division and differentiation in meristems
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DOI：
10.1105/tpc.105.036798
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发表时间：
2006-04-01
期刊：
影响因子：
11.6
通讯作者：
Morikami, A
中科院分区：
文献类型：
--
作者：
Inagaki, S;Suzuki, T;Morikami, A
在植物分生组织中，每个细胞以空间和时间调节的方式分裂和分化，并且使用来自分生组织的细胞发生连续的器官发生。我们报告的鉴定拟南芥TEBICHI（TEB）基因，这是需要调节细胞分裂和分化分生组织。teb突变体表现出形态缺陷，如短根、锯齿状叶片和扁平化，以及分生组织中细胞分裂和分化的缺陷模式。TEB基因编码果蝇MUS 308和哺乳动物DNA聚合酶theta的同源物，其防止自发或DNA损伤诱导的DNA双链断裂的产生。正如从动物同源物的功能所预期的，teb突变体显示组成型激活的DNA损伤反应。然而，与其他具有激活的DNA损伤反应的筋膜化突变体不同，teb突变体不激活转录沉默的基因。teb显示表达cyclinB 1;1：GUS的细胞在分生组织中积累，表明teb中组成性激活的DNA损伤反应导致G2/M细胞周期进程的缺陷。此外，其他的扁化突变体，如fasciata 2和tonsoku/mgoun 3/brushy 1，也显示了细胞表达cyclinB 1; 1：GUS在分生组织中的积累。这些结果表明，在G2/M的细胞周期进程是重要的细胞分裂和分化的模式在植物发育过程中的调节。
In plant meristems, each cell divides and differentiates in a spatially and temporally regulated manner, and continuous organogenesis occurs using cells derived from the meristem. We report the identification of the Arabidopsis thaliana TEBICHI (TEB) gene, which is required for regulated cell division and differentiation in meristems. The teb mutants show morphological defects, such as short roots, serrated leaves, and fasciation, as well as defective patterns of cell division and differentiation in the meristem. The TEB gene encodes a homolog of Drosophila MUS308 and mammalian DNA polymerase theta, which prevent spontaneous or DNA damage-induced production of DNA double strand breaks. As expected from the function of animal homologs, teb mutants show constitutively activated DNA damage responses. Unlike other fasciation mutants with activated DNA damage responses, however, teb mutants do not activate transcriptionally silenced genes. teb shows an accumulation of cells expressing cyclinB1;1:GUS in meristems, suggesting that constitutively activated DNA damage responses in teb lead to a defect in G2/M cell cycle progression. Furthermore, other fasciation mutants, such as fasciata2 and tonsoku/mgoun3/brushy1, also show an accumulation of cells expressing cyclinB1; 1: GUS in meristems. These results suggest that cell cycle progression at G2/M is important for the regulation of the pattern of cell division and of differentiation during plant development.