Vargas Lívia, Santa Brígida Ailton B, Mota Filho José P, de Carvalho Thais G, Rojas Cristian A, Vaneechoutte Dries, Van Bel Michiel, Farrinelli Laurent, Ferreira Paulo C G, Vandepoele Klaas, Hemerly Adriana S
Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Cidade Universitária, Rio de Janeiro, RJ, Brazil.
Laboratório de Biologia Molecular de Plantas, Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Cidade Universitária, Rio de Janeiro, RJ, Brazil; Universidade Federal da Integração Latino-Americana, Foz do Iguaçu, PR, Brazil.
PLoS One. 2014 Dec 9;9(12):e114744. doi: 10.1371/journal.pone.0114744. eCollection 2014.
Sugarcane interacts with particular types of beneficial nitrogen-fixing bacteria that provide fixed-nitrogen and plant growth hormones to host plants, promoting an increase in plant biomass. Other benefits, as enhanced tolerance to abiotic stresses have been reported to some diazotrophs. Here we aim to study the effects of the association between the diazotroph Gluconacetobacter diazotrophicus PAL5 and sugarcane cv. SP70-1143 during water depletion by characterizing differential transcriptome profiles of sugarcane. RNA-seq libraries were generated from roots and shoots of sugarcane plants free of endophytes that were inoculated with G. diazotrophicus and subjected to water depletion for 3 days. A sugarcane reference transcriptome was constructed and used for the identification of differentially expressed transcripts. The differential profile of non-inoculated SP70-1143 suggests that it responds to water deficit stress by the activation of drought-responsive markers and hormone pathways, as ABA and Ethylene. qRT-PCR revealed that root samples had higher levels of G. diazotrophicus 3 days after water deficit, compared to roots of inoculated plants watered normally. With prolonged drought only inoculated plants survived, indicating that SP70-1143 plants colonized with G. diazotrophicus become more tolerant to drought stress than non-inoculated plants. Strengthening this hypothesis, several gene expression responses to drought were inactivated or regulated in an opposite manner, especially in roots, when plants were colonized by the bacteria. The data suggests that colonized roots would not be suffering from stress in the same way as non-inoculated plants. On the other hand, shoots specifically activate ABA-dependent signaling genes, which could act as key elements in the drought resistance conferred by G. diazotrophicus to SP70-1143. This work reports for the first time the involvement of G. diazotrophicus in the promotion of drought-tolerance to sugarcane cv. SP70-1143, and it describes the initial molecular events that may trigger the increased drought tolerance in the host plant.
甘蔗与特定类型的有益固氮细菌相互作用，这些细菌为宿主植物提供固定氮和植物生长激素，促进植物生物量增加。据报道，一些固氮菌还有其他益处，比如增强对非生物胁迫的耐受性。在这里，我们旨在通过表征甘蔗的差异转录组图谱，研究固氮菌重氮营养醋杆菌PAL5与甘蔗品种SP70 - 1143之间的关联在水分亏缺期间的影响。RNA测序文库是从不含内生菌的甘蔗植株的根和茎中生成的，这些植株接种了重氮营养醋杆菌并经历了3天的水分亏缺。构建了甘蔗参考转录组并用于鉴定差异表达的转录本。未接种的SP70 - 1143的差异图谱表明，它通过激活干旱响应标记和激素途径（如脱落酸和乙烯）来应对水分亏缺胁迫。定量逆转录聚合酶链反应显示，与正常浇水的接种植物的根相比，水分亏缺3天后根样本中的重氮营养醋杆菌水平更高。随着干旱时间延长，只有接种的植物存活下来，这表明定殖有重氮营养醋杆菌的SP70 - 1143植物比未接种的植物对干旱胁迫更具耐受性。进一步支持这一假设的是，当植物被细菌定殖时，几种对干旱的基因表达反应被灭活或以相反的方式调节，尤其是在根中。数据表明，定殖的根与未接种的植物遭受胁迫的方式不同。另一方面，茎特异性激活依赖脱落酸的信号基因，这些基因可能是重氮营养醋杆菌赋予SP70 - 1143抗旱性的关键因素。这项工作首次报道了重氮营养醋杆菌参与提高甘蔗品种SP70 - 1143的耐旱性，并描述了可能引发宿主植物耐旱性增加的初始分子事件。
Zotero 插件
