Carol Rachel J, Dolan Liam
Department of Cell and Developmental Biology, John Innes Centre, Norwich Research Park, Colney Lane, Norwich, NR4 7UH, UK.
Philos Trans R Soc Lond B Biol Sci. 2002 Jun 29;357(1422):815-21. doi: 10.1098/rstb.2002.1092.
The Arabidopsis thaliana root hair is used as a model for studying tip growth in plants. We review recent advances, made using physiological and genetic approaches, which give rise to different, yet compatible, current views of the establishment and maintenance of tip growth in epidermal cells. For example, an active calcium influx channel localized at the tip of Arabidopsis root hairs has been identified by patch-clamp measurements. Actin has been visualized in vivo in Arabidopsis root hairs by using a green-fluorescent-protein-talin reporter and shown to form a dense mesh in the apex of the growing tip. The kojak gene, which encodes a protein similar to the catalytic subunit of cellulose synthase, is needed in the first stages of hair growth. A role for LRX1, a leucine-rich repeat extensin, in determining the morphology of the cell wall of root hairs has been established using reverse genetics. The new information can be integrated into a general and more advanced view of how these specialized plant cells grow.
拟南芥根毛被用作研究植物顶端生长的模型。我们综述了利用生理学和遗传学方法取得的最新进展，这些进展产生了关于表皮细胞顶端生长的建立和维持的不同但相互兼容的当前观点。例如，通过膜片钳测量在拟南芥根毛顶端鉴定出了一个活跃的钙内流通道。利用绿色荧光蛋白 - 踝蛋白报告基因在拟南芥根毛的体内可视化了肌动蛋白，并显示其在生长顶端的顶端形成密集的网络。kojak基因编码一种与纤维素合酶催化亚基相似的蛋白质，在毛发生长的第一阶段是必需的。利用反向遗传学确定了富含亮氨酸重复延伸蛋白LRX1在决定根毛细胞壁形态方面的作用。这些新信息可以整合到关于这些特殊植物细胞如何生长的更全面、更先进的观点中。
