Analysis of highly ordered architecture of actin cytoskeleton in plant cells.

植物细胞中肌动蛋白细胞骨架的高度有序结构分析。

• 批准号: 14540599
• 负责人: YOKOTA Etsuo
• 金额: $ 2.24万
• 依托单位: University of Hyogo (2004)Himeji Institute of Technology (2002-2003)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540599/
• 关键词: Actin binding protein; Villin; Actin; Pollen; Calcium ion; Lily; Profilin; Tobacco BY-2 cell; カルモジュリン

Plant villins, P-115-ABP and P-135-ABP, containing in a crude extract prepared from lily pollen. bound to a DNase I affinity column in the presence of Ca^<2+>, and were dissociated and eluted from the column with EGTA. Purified P-135-ABP accelerated the polymerization of G-actin in the presence of Ca^<2+>. These results indicated that P-135-ABP can form a complex with G-actin in the presence of Ca^<2+> and consequently acts as a nucleus or seed for polymerization of actin filaments. Furthermore, P-135-ABP caped an actin filament end, and severed or depolymerized filaments in the presence of Ca^<2+>. P-135-ABP has been shown to arrange actin filaments into bundles. Hence, like animal villin, P-135-ABP exerts various effects on actin in a Ca^<2+>-dependent manner. Based on an analysis of the primary structure of P-115-ABP, it is assumed that P-115-ABP also has similar activities to those of P-135-ABP. Hence, plant villin in pollen tubes is responsible for bundling actin filaments in shank region, where low concentrations of Ca^<2+> are present, while is involved in depolymerizing or severing actin filaments in apical regions, where relatively high concentrations of Ca^<2+> concentrations are present. In the presence of profilin, a low molecular weight G-actin binding protein, the acceleration of actin polymerization by P-135-ABP was not found. It is indicated that almost of G-actin form complex with profilin present at similar concentration to that of actin in the germinating pollen. Hence, it is reasonable to consider that actin-nucleation activity of plant villin is not exerted in pollen.Villin is widely distributed in plant cells, such as tobacco cultured cells BY-2. Interestingly, villin is co-localized with not only actin-filament bundles, but also certain organelles considered to be plastides. Therefore, it is possible that plant villin is one of factor responsible in the positioning of the organelles in cells.

植物绒毛蛋白，P-115-ABP和P-135-ABP，包含在百合花粉制备的粗提物中。在Ca^2+存在下结合到DNA酶I亲和柱上，解离并用EGTA从柱上洗脱。纯化的P-135-ABP在Ca^<2+>存在下可加速G-肌动蛋白的聚合。这些结果表明，P-135-ABP在Ca^2+存在下可与G-肌动蛋白形成复合物，从而作为肌动蛋白丝聚合的核或种子。此外，P-135-ABP覆盖了肌动蛋白丝末端，并在Ca^2+存在下切断或解聚了肌动蛋白丝。已显示P-135-ABP将肌动蛋白丝排列成束。因此，与动物绒毛蛋白一样，P-135-ABP以Ca^2+依赖的方式对肌动蛋白发挥各种作用。基于对P-115-ABP的一级结构的分析，推测P-115-ABP也具有与P-135-ABP相似的活性。因此，植物花粉管中的绒毛蛋白在柄部区域负责将肌动蛋白丝成束，而在顶端区域则参与解聚或切断肌动蛋白丝，柄部区域存在低浓度的Ca^<2+>，而顶端区域存在相对高浓度的Ca^<2+>。在低分子量的G-肌动蛋白结合蛋白profilin存在下，P-135-ABP对肌动蛋白聚合的促进作用不明显，表明在萌发花粉中，几乎所有的G-肌动蛋白都能与profilin形成复合物。植物绒毛蛋白广泛存在于植物细胞中，如烟草培养细胞BY-2。有趣的是，绒毛蛋白不仅与肌动蛋白丝束共定位，而且与某些被认为是质体的细胞器共定位。因此，植物绒毛蛋白可能是负责细胞器定位的因素之一。

项目成果

E.Yokota: "Plant 115-kDa-actin-filament-bundling protein, P-115-ABP, is a homologue of plant villin and is widely distributed in cells."Plant Cell Physiol.. 44. 1088-1099 (2003)

E.Yokota：“植物 115-kDa-肌动蛋白丝束蛋白，P-115-ABP，是植物绒毛蛋白的同源物，广泛分布在细胞中。”Plant Cell Physiol.. 44. 1088-1099 (2003)

21-kDa polypeptide, a low-molecular-weight cyclophilin, is released from pollen of higher plants into the extracellular medium in vitro

• DOI: 10.1007/s00425-003-1177-2
• 发表时间: 2004-01
• 期刊: Planta
• 影响因子: 4.3
• 作者: E. Yokota;T. Ohmori;S. Muto;T. Shimmen

E.Yokota: "Possible involvement of energy metabolism in the change of cytoplasm organization induced by a protein phosphatase inhibitor, calyculin A, in root hair cells of Limnobium."Protoplasma. 221. 217-226 (2003)

E.Yokota：“能量代谢可能参与由蛋白磷酸酶抑制剂花萼蛋白 A 在 Limnobium 根毛细胞中诱导的细胞质组织变化。”原生质体。

E.Yokota: "21-kDa polypeptide, a low molecular weight cyclophilin, is released from pollen grain of higher plants into extracellular medium in vitro."Planta. (印刷中).

E. Yokota：“21-kDa 多肽是一种低分子量亲环蛋白，在体外从高等植物的花粉粒释放到细胞外培养基中。”Planta（正在出版）。

Plant 115-kDa actin-filament bundling protein, P-115-ABP, is a homologue of plant villin and is widely distributed in cells.

• DOI: 10.1093/pcp/pcg132
• 发表时间: 2003-10
• 期刊: Plant & cell physiology
• 影响因子: 4.9
• 作者: E. Yokota;L. Vidali;M. Tominaga;H. Tahara;H. Orii;Yosuke Morizane;P. K. Hepler;T. Shimmen