【植物应对盐胁迫】Carlos S. Galvan-Ampudia Magdalena M. Julkowska Essam Darwish Jacinto Gandullo Ruud A. Korver Geraldine Brunoud Michel A. Haring Teun Munnik Teva Vernoux Christa Testerink. Halotropism Is a Response of Plant Roots to Avoid a Saline Environment. Current Biology Volume 23 Issue 20 2044-2050 03 October 2013

Abstract

Tropisms represent fascinating examples of how plants respond to environmental signals by adapting their growth and development. Here a novel tropism is reported halotropism allowing plant seedlings to reduce their exposure to salinity by circumventing a saline environment. In response to a salt gradient Arabidopsis tomato and sorghum roots were found to actively prioritize growth away from salinity above following the gravity axis. Directionality of this response is established by an active redistribution of the plant hormone auxin in the root tip which is mediated by the PIN-FORMED 2 (PIN2) auxin efflux carrier. We show that salt-induced phospholipase D activity stimulates clathrin-mediated endocytosis of PIN2 at the side of the root facing the higher salt concentration. The intracellular relocalization of PIN2 allows for auxin redistribution and for the directional bending of the root away from the higher salt concentration. Our results thus identify a cellular pathway essential for the integration of environmental cues with auxin-regulated root growth that likely plays a key role in plant adaptative responses to salt stress.

【蔬菜作物对抗生素的吸收】Dong Hee Kang † Satish Gupta *† Carl Rosen † Vincent Fritz ‡§ Ashok Singh Yogesh Chander