Bhoomika Kumari, Pyngrope Samantha, Dubey Rama S
Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India.
Department of Biochemistry, Faculty of Science, Banaras Hindu University, Varanasi 221005, India.
J Plant Physiol. 2014 Apr 15;171(7):497-508. doi: 10.1016/j.jplph.2013.12.009. Epub 2014 Mar 13.
The effect of toxic concentrations of aluminum (Al) was investigated on contents of protein-thiols, non-protein and total thiols, protein carbonylation and protease activity in the seedlings of Al-sensitive (Al-S) Indica rice cv. HUR-105 and Al-tolerant (Al-T) cv. Vandana grown in sand cultures. Al treatment of 178 μM and 421 μM for 3-12 days caused a significant decline in the level of protein thiols, rise in non-protein thiols (NPTs) as well as protein carbonyl content and an insignificant alteration in the level of total thiols in cv. HUR-105 seedlings. However, in the seedlings of Al-T cv. Vandana, no significant alteration could be observed on any of these parameters with Al treatment. Al treatment inhibited protease activity in roots, whereas the opposite trend was seen in shoots. New isozymes of protease appeared in shoots of cv. Vandana with increased level of Al treatment. Our results show a link between protein thiols and NPTs and suggest the role of NPTs in the repair and protection of protein thiols. Inhibitory effect of Al on protease activity in roots could be a major reason for Al rhizotoxic effects. Al tolerance in rice appears to be associated with lesser content of protein thiols in roots, smaller amount of carbonylated proteins in roots as well as shoots and higher protease activity in shoots.
研究了有毒浓度的铝（Al）对砂培条件下铝敏感型（Al-S）籼稻品种HUR-105和铝耐受型（Al-T）品种Vandana幼苗中蛋白质硫醇、非蛋白质硫醇和总硫醇含量、蛋白质羰基化和蛋白酶活性的影响。对HUR-105幼苗进行178μM和421μM的铝处理3至12天，导致蛋白质硫醇水平显著下降，非蛋白质硫醇（NPTs）水平和蛋白质羰基含量上升，总硫醇水平无显著变化。然而，在铝耐受型品种Vandana的幼苗中，铝处理后这些参数均未观察到显著变化。铝处理抑制了根中的蛋白酶活性，而在地上部分则观察到相反的趋势。随着铝处理水平的增加，Vandana品种地上部分出现了新的蛋白酶同工酶。我们的结果表明蛋白质硫醇和NPTs之间存在联系，并表明NPTs在蛋白质硫醇的修复和保护中发挥作用。铝对根中蛋白酶活性的抑制作用可能是铝产生根毒性效应的主要原因。水稻的铝耐受性似乎与根中较低的蛋白质硫醇含量、根和地上部分较少的羰基化蛋白质以及地上部分较高的蛋白酶活性有关。
