A model to explain ion-induced differentiation in zoospores ofPhytophthora palmivora |
| |
| Institution: | 1. Department of Chemistry, Umeå University, Umeå, Sweden;2. Institut de Química Computacional i Catàlisi, Universitat de Girona, Girona, 17003, Spain;1. School of Science, RMIT University, Melbourne, Vic, 3001, Australia;2. School of Life Sciences, University of Technology Sydney, Ultimo, NSW 2007, Australia;3. Department of Biomedicine, University of Aarhus, DK-8000 Aarhus, C, Denmark;4. School of Chemistry, University of Sydney, Sydney, NSW 2006, Australia;5. The University of Sydney Nano Institute, Sydney, NSW 2006, Australia |
| |
| Abstract: | Zoospores ofPhytophthora palmivora undergo synchronous encystment followed by germination when exposed to sodium ions at 3–10 mM, calcium ions at 5–30 mM, and strontium ions at 0.3–10 mM. Lithium ions induce encystment at 3–10 mM but do not induce germination. Ferric, manganese, and barium ions.act as chaotropic agents, damaging the zoospore plasma membrane under both isoosmotic and hypoosmotic conditions, at concentrations as low as 30 μM, ferric ions and 1 mM, barium ions. Cesium and ammonium ions are cytotoxic and induce lysis under hypoosmotic conditions. The capacity of cations to induce zoospore differentiation can be explained in terms of the following model. It is suggested that differentiation inP. palmivora requires the entry of sodium at one or more specific sites. Access to these sites is regulated by a calcium gated monovalent ion translocator with a high specificity for sodium. Calcium not only regulates sodium ion access but also regulates the cell's osmoregulatory system. Divalent cations act by competing for the calcium binding site, monovalent cations by restricting fodium ion access. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
