Groten Karin, Dutilleul Christelle, van Heerden Philippus D R, Vanacker Hélène, Bernard Stéphanie, Finkemeier Iris, Dietz Karl-Josef, Foyer Christine H
Crop Performance and Improvement Division, Rothamsted Research, West Common, Harpenden, Hertfordshire AL5 2JQ, UK.
FEBS Lett. 2006 Feb 20;580(5):1269-76. doi: 10.1016/j.febslet.2006.01.043. Epub 2006 Jan 23.
Redox factors contributing to nodule senescence were studied in pea. The abundance of the nodule cytosolic peroxiredoxin but not the mitochondrial peroxiredoxin protein was modulated by ascorbate. In contrast to redox-active antioxidants such as ascorbate and cytosolic peroxiredoxin that decreased during nodule development, maximal extractable nodule proteinase activity increased progressively as the nodules aged. Cathepsin-like activities were constant throughout development but serine and cysteine proteinase activities increased during senescence. Senescence-induced cysteine proteinase activity was inhibited by cysteine, dithiotreitol, or E-64. Senescence-dependent decreases in redox-active factors, particularly ascorbate and peroxiredoxin favour decreased redox-mediated inactivation of cysteine proteinases.
对豌豆中导致根瘤衰老的氧化还原因子进行了研究。根瘤胞质过氧化物酶体增殖蛋白的丰度受到抗坏血酸的调节，但线粒体过氧化物酶体增殖蛋白不受影响。与在根瘤发育过程中减少的氧化还原活性抗氧化剂如抗坏血酸和胞质过氧化物酶体增殖蛋白相反，随着根瘤老化，最大可提取的根瘤蛋白酶活性逐渐增加。在整个发育过程中，组织蛋白酶样活性保持恒定，但丝氨酸和半胱氨酸蛋白酶活性在衰老过程中增加。衰老诱导的半胱氨酸蛋白酶活性受到半胱氨酸、二硫苏糖醇或E-64的抑制。氧化还原活性因子，特别是抗坏血酸和过氧化物酶体增殖蛋白的衰老依赖性降低，有利于减少半胱氨酸蛋白酶的氧化还原介导的失活。
