Stress perception and communication play important roles in the adaptation of plants to changing environmental conditions. Plant roots are the first organs to detect changes in the soil water potential induced by salt stress. In the presence of salinity stress, root-to-shoot communication occurs to adjust the growth of the whole plant. So far, the phytohormone abscisic acid (ABA), hydraulic signals and reactive oxygen species (ROS) have been proposed to mediate this communication under salt stress. Recently, we identified the rice transcription factor SALT-RESPONSIVE ERF1 (SERF1), which regulates a ROS-dependent transcriptional cascade in roots required for salinity tolerance. Upon salt stress, SERF1 knockout mutant plants show an increased leaf temperature as compared with wild type. As this occurs within the first 20 min of salt stress, we here evaluated the involvement of SERF1 in the perception of salt stress in the shoot. By metabolic profiling and expression analysis we show that the action of SERF1 in signal communication to the shoot is independent from ABA, but does affect the accumulation of ROS-related metabolites and transcripts under short-term salt stress.
脅迫感知能力和信號(hào)交流在植物適應(yīng)變化的環(huán)境條件中起著重要作用，植物根系是第一個(gè)監(jiān)測鹽脅迫誘導(dǎo)土壤水勢變化的器官。在鹽脅迫條件下，根到地上部之間信號(hào)交流的發(fā)生是為了調(diào)節(jié)整個(gè)植株的生長。至今，植物激素ABA、水壓信號(hào)、活性氧被認(rèn)為是介導(dǎo)了鹽脅迫下的信號(hào)交流。目前，我們鑒定了水稻轉(zhuǎn)錄因子SALT-RESPONSIVE ERF1（SERF1），該因子調(diào)節(jié)根系耐鹽應(yīng)答過程中必需的一個(gè)依賴ROS的聯(lián)反應(yīng)。鹽脅迫下，SERF1敲出突變體植株與野生型相比，葉片溫度略有增高。當(dāng)該現(xiàn)象發(fā)生在鹽脅迫的前20分鐘內(nèi)，我們?cè)u(píng)價(jià)了SERF1參與的地上部鹽脅迫的感知效應(yīng)。通過代謝譜和表達(dá)分析，我們發(fā)現(xiàn)SERF1在地上部信號(hào)交流通路中的作用是獨(dú)立于ABA的，但是的確影響了短期鹽脅迫條件下ROS相關(guān)代謝產(chǎn)物和轉(zhuǎn)錄本的積累。