Signal transduction pathways regulating cortical microtubule functions

调节皮质微管功能的信号转导途径

• 批准号: 18370020
• 负责人: HASHIMOTO Takashi
• 金额: $ 10.99万
• 依托单位: Nara Institute of Science and Technology
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2006
• 资助国家: 日本
• 起止时间: 2006 至 2007
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18370020/
• 关键词: Arabidopsis; microtubule; signal transduction; phosphorylation

Many extragenic suppressors were obtained after EMS-mutagenesis of the semi-dominant phs1-1 allele. A group of suppressors did not follow a Mendelian segregation and could not be mapped in this study. Other suppressors were shown to have mis-sense mutations in Arabidopsis tubulin genes.Full length PHS1 cDNAs of wild type and the phs1-1-type mutantation were used to screen Arabidopsis cDNA libraries by a yeast two-hybrid method, bud did not result in positive clones.When a phosphatase-dead mutant of PHS1 was expressed in plant cells, it strongly induced depolymerization of cortical microtubules. This dominant-negative effect was specific to PHS1 since similar phosphatase-dead mutants of other four Arabidopsis MAP kinase phosphatases did not affect cortical microtubule organization. PHS1 is positively retained in the cytoplasm. A C-terminal region excluding the phosphatase catalytic domain was necessary and sufficient for the cytoplasmic retention. Possibly, PHS1 may dephosporylate microtubule-related factors in the cytoplasm.While screening downstream targets of PHS1, we found that Ser-172 of β-tubulin is phosphorylated, cyclin-dependent kinases catalyze this phosphorylation, and the phosphorylated b-tubulin significantly accumulates in an Arabidopsis ton2 mutant of a regulatory subunit in the PP2A phosphatase.

EMS诱变半显性phs 1 -1等位基因后获得了许多基因外抑制子。一组抑制基因没有遵循孟德尔分离，在这项研究中无法定位。利用酵母双杂交技术筛选拟南芥cDNA文库，未得到阳性克隆，而PHS 1的磷酸酶失活突变体在植物细胞中表达后，能强烈诱导皮层微管的解聚。这种显性负效应是特定的PHS 1，因为类似的磷酸酶死亡突变体的其他四个拟南芥MAP激酶磷酸酶不影响皮层微管组织。PHS 1阳性保留在细胞质中。一个C-末端区域不包括磷酸酶催化结构域是必要的和足够的细胞质保留。在筛选PHS 1下游靶点时，我们发现β-tubulin的Ser-172被磷酸化，细胞周期蛋白依赖性激酶催化这种磷酸化，磷酸化的b-tubulin在PP 2A磷酸酶调节亚基的拟南芥ton 2突变体中显著积累。

项目成果

Twisted growth and organization of cortical microtubules

• DOI: 10.1007/s10265-006-0039-y
• 发表时间: 2007-01-01
• 期刊: JOURNAL OF PLANT RESEARCH
• 影响因子: 2.8
• 作者: Ishida, Takashi;Thitamadee, Siripong;Hashimoto, Takashi
• 通讯作者: Hashimoto, Takashi

微小管構築の遺伝学的解析

微管组装的遗传分析

• 发表时间: 2008
• 作者: T. Ishida;et. al.;T.Ishida;T. Shoji;T. Shoji;濱田 隆宏;T. Hamada;橋本 隆
• 通讯作者: 橋本 隆

An Arabidopsis thaliana tubulin mutant with conditional root-skewing phenotype

具有条件根偏斜表型的拟南芥微管蛋白突变体

• 发表时间: 2007
• 期刊: J. Plant Res. 120
• 作者: Y. Takeuchi;K. Sato and Y. Iwasaeds;M. Yao;M. Yao;T. Ishida;T. Ishida
• 通讯作者: T. Ishida

サイクリン依存性キナーゼ群が関与する微小管の制御機構

涉及细胞周期蛋白依赖性激酶的微管控制机制

• 发表时间: 2008
• 作者: T. Ishida;et. al.;T.Ishida;T. Shoji;T. Shoji;濱田 隆宏
• 通讯作者: 濱田 隆宏

表層微小管の配向に関与するPHS1に遺伝学的相互作用する因子の検索

寻找与 PHS1 遗传相互作用的因子，PHS1 参与表面微管的定向

• 发表时间: 2007
• 作者: T. Ishida;et. al.;T.Ishida;T. Shoji;T. Shoji;濱田 隆宏;T. Hamada;橋本 隆;T. Hashimoto;橋本 隆;加藤 壮英
• 通讯作者: 加藤 壮英