期刊
PLANT AND CELL PHYSIOLOGY
卷 56, 期 9, 页码 1711-1720出版社
OXFORD UNIV PRESS
DOI: 10.1093/pcp/pcv100
关键词
Ca2+-permeable channels; Cytosolic Ca2+ concentration; Ethylene; ROS; Transfer cell; Vicia faba
资金
- Australian Research Council [DP0664626]
- University of Newcastle
- Australian Research Council [DP0664626] Funding Source: Australian Research Council
The enhanced transport capability of transfer cells (TCs) arises from their ingrowth wall architecture comprised of a uniform wall on which wall ingrowths are deposited. The wall ingrowth papillae provide scaffolds to amplify plasma membranes that are enriched in nutrient transporters. UsingVicia faba cotyledons, whose adaxial epidermal cells spontaneously and rapidly (hours) undergo a synchronous TC rans-differentiation upon transfer to culture, has led to the discovery of a cascade of inductive signals orchestrating deposition of ingrowth wall papillae. Auxin-induced ethylene biosynthesis initiates the cascade. This in turn drives a burst in extracellular H2O2 production that triggers uniform wall deposition. Thereafter, a persistent and elevated cytosolic Ca2+ concentration, resulting from Ca2+ influx through plasma membrane Ca2+-permeable channels, generates a Ca2+ signal that directs formation of wall ingrowth papillae to specific loci. We now report how these Ca2+-permeable channels are regulated using the proportionate responses in cytosolic Ca2+ concentration as a proxy measure of their transport activity. Culturing cotyledons on various combinations of pharmacological agents allowed the regulatory influence of each upstream signal on Ca2+ channel activity to be evaluated. The findings demonstrated that Ca2+-permeable channel activity was insensitive to auxin, but up-regulated by ethylene through two independent routes. In one route ethylene acts directly on Ca2+-permeable channel activity at the transcriptional and post-translational levels, through an ethylene receptor-dependent pathway. The other route is mediated by an ethylene-induced production of extracellular H2O2 which then acts translationally and post-translationally to up-regulate Ca2+-permeable channel activity. A model describing the differential regulation of Ca2+-permeable channel activity is presented.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据