一个RhoGDP解离抑制剂在空间上调节根毛细胞的生长
Rachel J Carol1, Seiji Takeda, Paul Linstead
1Department of Cell and Developmental Biology, John Innes Centre, Norwich NR4 7UH, UK.
Nature
|December 16, 2005
概括
植物根毛通过尖端生长,一个极化细胞扩张生长. 确定了一种RhoGTPase GDP解离抑制剂 (RhoGDI) 蛋白质SCN1,该蛋白质限制了尖端的生长,将重点放在反应性氧物种的生产上,以促进正常的根毛发育.
科学领域:
- 植物生物学 植物生物学
- 细胞生长机制 细胞生长机制
- 分子植物科学 分子植物科学
背景情况:
- 根毛对于营养吸收至关重要,通过尖端生长延伸到土壤中.
- 尖端生长涉及极化细胞扩张,仅限于三细胞尖端.
- 局部反应性氧物种 (ROS) 生产对于根毛延长至关重要.
研究的目的:
- 为了确定控制植物根毛中细胞生长空间调节的蛋白质.
- 研究SCN1基因在根毛尖生长中的作用.
- 阐明了将ROS生产集中在根头发尖端的机制.
主要方法:
- 隔离和表征具有异胎生长部位的阿拉比多普西斯突变物 (scn1).
- 基因克隆和识别SCN1作为RhoGTPase GDP解离抑制剂 (RhoGDI).
- 分析SCN1在聚焦RHD2/AtrbohCNADPH氧化酶活性中的作用.
主要成果:
- 这种scn1突变体在三细胞上表现出宫外生长部位,表明失去了生长空间控制.
- 确定了SCN1,RhoGDI,并表明它可以将生长限制在三细胞的单个部位上.
- SCN1是将RHD2/AtrbohC介导的ROS产量集中到根头发尖端的组成部分.
结论:
- SCN1/AtrhoGDI1是一个关键的调节器,它在空间上限制了根头发尖的生长.
- 这项研究提出了一个模型,其中RhoGDI调节的NADPH氧化酶激活聚焦ROS生产以实现极化生长.
- 了解这种机制对于植物的发育和营养获取至关重要.
相关概念视频
02:19Morphogenesis
20.0K
Plant morphogenesis—the development of a plant’s form and structure—involves several overlapping developmental processes, including growth and cell differentiation. Precursor cells differentiate into specific cell types, which are organized into the tissues and organ systems that make up the functional plant.
20.0K
02:34Water and Mineral Acquisition
24.4K
Specialized tissues in plant roots have evolved to capture water, minerals, and some ions from the soil. Roots exhibit a variety of branching patterns that facilitate this process. The outermost root cells have specialized structures called root hairs that increase the root surface, thus increasing soil contact. Water can passively cross into roots, as the concentration of water in the soil is higher than that of the root tissue. Minerals, in contrast, are actively transported into root cells.
24.4K
02:12Short-distance Transport of Resources
14.9K
Short-distance transport refers to transport that occurs over a distance of just 2-3 cells, crossing the plasma membrane in the process. Small uncharged molecules, such as oxygen, carbon dioxide, and water, can diffuse across the plasma membrane on their own. In contrast, ions and larger molecules require the assistance of transport proteins due to their charge or size. Transport across membranes also occurs within individual cells, playing a variety of essential roles for the plant as a whole.
14.9K
01:21Cell Polarization by Rho Proteins
3.2K
Cell polarity is the asymmetric distribution of cellular and membrane components, making one side of the cell different from the other. This polarity is essential to many processes such as embryogenesis, axon migration, glucose transport across epithelial cells, and directional cell migration. A migrating cell responds to intracellular or extracellular signals via molecular cascades that reorganize the actin cytoskeleton to establish this polarity. In these cells, the Rho family proteins Cdc42,...
3.2K
01:24Small GTPases - Ras and Rho
4.4K
Ras and Rho are small monomeric GTPases that act downstream of receptor tyrosine kinase (RTK) and regulate various cellular processes. These GTPases switch between active and inactive states by binding to guanine nucleotides.
Three regulatory proteins control their activity:
Three regulatory proteins control their activity:
4.4K
01:22Activation and Inactivation of G Proteins
8.9K
Heterotrimeric G proteins are guanine nucleotide-binding proteins. As the name suggests, heterotrimeric G proteins are composed of three subunits: alpha, beta, and gamma. They remain GDP-bound or GTP-bound inside the cells and switch between inactive/active states. The Gα subunit possesses the nucleotide-binding pocket that binds guanine nucleotides and switches between GDP or GTP-bound states. In contrast, the Gꞵ and Gγ subunits are always bound together with high...
8.9K