Elucidation of the regulation mechanism of gene expression in the totipotency of plant cells

植物细胞全能性基因表达调控机制的阐明

• 批准号: 05404004
• 负责人: NAGATA Toshiyuki
• 金额: $ 22.27万
• 依托单位: University of Tokyo, Graduate School of Science
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (A)
• 财政年份: 1993
• 资助国家: 日本
• 起止时间: 1993 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05404004/
• 关键词: totipotency; dedifferentiation; redifferentiation; auxin; cytokinin; transcriptional regulation; signal transduction chain; embryogenesis; Gタンパク質; 遺伝子発現

Though the totipotency of plant cells is said to be the most characteristic features of plant and it is used as the main means of plant biotechnology, its molecular mechanism is least elucidated. In this study, the totipotency has been studied at the three phases ; the dedifferentiation of differentiated somatic cells, the maintenance of these cells that regain cell division activity and the redifferentiation of these cells to whole plants. Since two plant hormones of auxin and cytokinin have been shown to be most influential in all of these three processes, the molecular mode of these two plant hormones has been intensively studied in respective three stages. Regarding the dedifferentiation process, we have isolated three auxin-regulated genes, parA,parB and parC,from the early stage of cultured tobacco mesophyll protoplasts. Thus we tried to elucidate the transcriptional regulation of these genes. Our efforts identified auxin-responsive elements in these genes and in particular, in t … More he parB promoter. Furthermore, we have identified a protein that binds to one of auxin-responsive element, which is classified as one of b-ZIPs. We have also identified a cytokinin-regulated gene as the first case in this category. Though the characterization of this cytokinin-regulated gene is currently under study, it seems to belong to arabinogalactan-related proteins. Subsequently we have identified arcA gene as an auxin-regulated gene in the actively dividing tobacco BY-2 cells. arcA has been found to be a homologue of receptor for activated C-Kinase. Furthermore, a protein that could have protein-protein interaction with this arcA protein has been indentified by means of the yeast two-hybrid system. This protein is a homologue of beta-subunit of K^+-channel. Thus it became certain that there is a novel signal transduction chain down-stream of auxin application, resulting in the cell division of cultured cells.On the other hand, we have identified two auxin-regulated genes in the early stage of embryogenesis of carrot epidermis tissues. One is found to be a homologue of parA,while the other is found to be a homologue of low-molecular weight heat shock proteins.Thus in this study we have identified several molecules that are involved in different phases of totipotency. Though full details of totipotency still remains to be elucidated, general features of totipotency has been shown in this study. Less

尽管据说植物细胞的全能是植物的最特征，它被用作植物生物技术的主要手段，但其分子机制最少阐明。在这项研究中，已经在三个阶段进行了研究。分化的体细胞的去分化，这些细胞的维持，这些细胞恢复了细胞分裂活性，并将这些细胞的分化为整个植物。由于生长素和细胞分裂素的两种植物恐怖在这三个过程中都具有最大的影响力，因此这两种植物马的分子模式已经在相对三个阶段进行了强化研究。关于去分化过程，我们从培养的烟草叶叶叶植物的早期阶段分离出了三个由生长素调节的基因，Para，Parb和Parc。我们试图阐明这些基因的转录调节。我们的努力确定了这些基因的生长素响应元素，尤其是在……更多的启动子中。此外，我们已经确定了一种与生长素反应元件之一结合的蛋白质，该蛋白被归类为B-ZIPS之一。我们还确定了细胞分裂素调节的基因是该类别中的第一种情况。尽管目前正在研究该细胞分裂素调节的基因的表征，但它似乎属于与阿拉伯分离的蛋白。随后，我们将ARCA基因确定为活跃分裂的烟草BY-2细胞中的生长素调节基因。已发现ARCA是激活C-激酶受体的同源物。此外，一种可能与该ARCA蛋白质蛋白质相互作用的蛋白质已通过酵母两杂交系统的抑制作用。该蛋白是K^+通道的β-亚基的同源物。可以肯定的是，生长素施用的新型信号转导链下游，导致培养细胞的细胞分裂。另一方面，我们在胡萝卜表皮组织的胚胎发生的早期阶段鉴定了两个辅助蛋白调节的基因。发现一种是Para的同源物，而另一个是低分子量热电冲击蛋白的同源物。在这项研究中，我们已经确定了几个与不同阶段相关的分子。尽管关于能力的完整详细信息仍然有待阐明，但在本研究中已经显示了全能性的一般特征。较少的

项目成果

Sakai, T., Takahashi, Y.and Nagata, T.: "Analysis of the promoter of the auxin-inducible gene, parC,of tobacco." Plant Cell Physiol.37. 906-913 (1996)

Sakai, T.、Takahashi, Y. 和 Nagata, T.：“烟草生长素诱导基因 parC 启动子的分析”。

Isida S.et al.: "The mode of expression and promoter analysis of the arcA gene,an auxin-regulated gene in tobacco BY-2 cells." Plant Cell Physiol.37. 439-448 (1996)

Isida S.et al.：“烟草 BY-2 细胞中生长素调节基因 arcA 基因的表达模式和启动子分析。”

Kusaba,M.et al.: "A multiple-stimuli-responsive as-1-related element of parA gene confers responsiveness to cadmium but not copper." Plant Physiol.111. 1161-1167 (1996)

Kusaba,M.等人：“parA 基因的多重刺激响应 as-1 相关元件赋予对镉的响应性，但对铜没有响应性。”

Ishida, S., Takahashi, Y.and Nagata, T.: "The mode of expression and promoter analysis of the arcA gene, an auxin-regulated gene in tobacco BY-2 cells." Plant Cell Physiol.37. 439-448 (1996)

Ishida, S.、Takahashi, Y. 和 Nagata, T.：“烟草 BY-2 细胞中生长素调节基因 arcA 基因的表达模式和启动子分析。”

Mitsui, H., Hasezawa, S., Nagata, T.and Takahashi, H.: "Cell cycle-dependent accumulation of a kinesin-like protein, Kat B/C,in synchronized tobacco BY-2 cells." Plant Mol.Biol.30. 177-181 (1996)

Mitsui, H.、Hasezawa, S.、Nagata, T. 和 Takahashi, H.：“同步烟草 BY-2 细胞中驱动蛋白样蛋白 Kat B/C 的细胞周期依赖性积累。”