昆明植物所揭示抗逆植物马齿苋耐高温高湿的调控机制

恶魔般旳霸道

昆明植物所揭示抗逆植物马齿苋耐高温高湿的调控机制  关注儿童辅食批发，有帮助！

        马齿苋(Portulaca olerAcea)是马齿苋科(Portulacaceae)一年生肉质草本植物，因其生命力极强，具有很强的耐干旱、高温、营养贫瘠等能力，又有“长寿菜”之称。研究马齿苋抗逆的内在机制，探索马齿苋响应逆境的调控方式，为作物作良与种质创新提供了新的素材。植物蛋白组学方法为植物逆境生理学研究提供了一条快捷而有效的方式，为全面解析植物响应逆境的分子机制提供了可能。

        高温与高湿作为两种十分普遍的逆境因子，限制了诸多植物的生长发育与作物产量。在热带地区，高温通常伴随着高湿环境联合作用，但是植物响应高温高湿环境胁迫的内在机制并不十分清楚。中科院昆明植物研究所胡向阳研究组与杨永平研究组利用马齿苋为材料，通过蛋白组学与生理学等手段解析了马齿苋对高温高湿环境胁迫的响应机制。

        结果表明，相比其它植物如拟南芥(Arabidopsis)而言，马齿苋明显地耐受高温高湿环境胁迫。在这一过程中，脱落酸(ABA)降解途径明显被激活并抑制ABA的过度积累，从而保持叶片气孔处在打开状态，促进了叶片蒸腾作用以有效降低叶片温度;同时，诱导热休克蛋白积累与提高抗氧化酶活性以避免高湿高湿引起的细胞过氧化损伤;脯氨酸代谢途径也被明显激活产生大量脯氨酸以保护细胞机能。以上结果表明，在高温高湿逆境胁迫下，马齿苋调动多种策略增强对逆境胁迫的适应性。

        以上结果已被蛋白组学专业期刊Journal of Proteome Research 在线发表。该研究得到中科院“百人计划”与国家自然科学基金项目的资助。

       

        马齿苋耐高温高湿的调控机制研究

        原文摘要：

        Comparative Proteomic Analysis of the thermotolerant Plant Portulaca oleracea Acclimation to Combined High Temperature and Humidity Stress

        Elevated temperature and humidity are major environmental factors limiting crop yield and distribution. An understanding of the mechanisms underlying plant tolerance to high temperature and humidity may facilitate the development of cultivars adaptable to warm or humid regions. Under conditions of 90% humidity and 35 °C, the thermotolerant plant Portulaca oleracea exhibits excellent photosynthetic capability and relatively little oxidative damage. To determine the proteomic response that occurs in leaves of P. oleracea following exposure to high temperature and high humidity, a proteomic approach was performed to identify protein changes. A total of 51 differentially expressed proteins were detected and characterized functionally and structurally; these identified proteins were involved in various functional categories, mainly including material and energy metabolism, the antioxidant defense responses, protein destination and storage, and transcriptional regulation. The subset of antioxidant defense-related proteins demonstrated marked increases in activity with exposure to heat and humidity, which led to lower accumulations of H2O2 and O2– in P. oleracea compared with the thermosensitive plant Arabidopsis thaliana. The quickly accumulations of proline content and heat-shock proteins, and depleting abscisic acid (ABA) via increasing ABA-8′-hydroxylase were also found in P. oleracea under stress conditions, that resulted into greater stomata conductance and respiration rates. On the basis of these findings, we propose that P. oleracea employs multiple strategies to enhance its adaptation to high-temperature and high-humidity conditions.