Plant Molecular and Cellular Biology Program, Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, USA.
Planta. 2010 Jan;231(2):361-9. doi: 10.1007/s00425-009-1055-7. Epub 2009 Nov 21.
A glutaredoxin of the fern Pteris vittata PvGRX5 was previously implicated in arsenic tolerance. Because of possible involvements of glutaredoxins in metabolic adaptations to high temperature stress, transgenic Arabidopsis lines constitutively expressing PvGRX5 were evaluated for thermotolerance. Homozygous lines expressing PvGRX5 exhibited significantly greater tolerance to high temperature stress than the vector control and wild-type, based upon growth during stress and during recovery from stress, and this was related to leaf glutaredoxin specific activities. Measurements of tissue ion leakage, thiobarbituric acid reactive substances and protein carbonyl content showed that PvGRX5-expressors were significantly (P < 0.05) less affected by the high temperature treatment compared to wild-type and vector control lines for damage to membranes and proteins. Immunoblots indicated that specific protein bands, carbonylated during the stress treatment in the control lines, were protected in PvGRX5-expressors, thus implicating PvGRX5 in heat tolerance, likely mediated through cellular protection against oxidative stress.
先前有研究表明，凤尾蕨 PvGRX5 是一种参与砷耐受的谷氧还蛋白。由于谷氧还蛋白可能参与了对高温胁迫的代谢适应，因此对组成型表达 PvGRX5 的拟南芥转基因系进行了耐热性评估。基于胁迫期间和胁迫后恢复期间的生长情况，表达 PvGRX5 的纯合系比载体对照和野生型表现出显著更高的高温胁迫耐受性，这与叶片谷氧还蛋白比活力有关。组织离子渗漏、硫代巴比妥酸反应物质和蛋白质羰基含量的测量表明，与野生型和载体对照系相比，PvGRX5 表达系受高温处理对膜和蛋白质的损伤的影响明显较小（P < 0.05）。免疫印迹表明，在对照系中应激处理过程中发生羰基化的特定蛋白质条带在 PvGRX5 表达系中得到了保护，这表明 PvGRX5 参与了耐热性，可能通过细胞抗氧化应激来介导。
