LEAF SENESCENCE - CORRELATED WITH INCREASED LEVELS OF MEMBRANE-PERMEABILITY AND LIPID-PEROXIDATION, AND DECREASED LEVELS OF SUPEROXIDE-DISMUTASE AND CATALASE
LEAF SENESCENCE - CORRELATED WITH INCREASED LEVELS OF MEMBRANE-PERMEABILITY AND LIPID-PEROXIDATION, AND DECREASED LEVELS OF SUPEROXIDE-DISMUTASE AND CATALASE
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DOI：
10.1093/jxb/32.1.93
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发表时间：
1981-01-01
影响因子：
6.9
通讯作者：
THORPE, TA
中科院分区：
文献类型：
--
作者：
DHINDSA, RS;PLUMBDHINDSA, P;THORPE, TA
以烟草（Nicotiana tabacum L.）叶片为材料，研究了叶片原位衰老过程中膜透性（可溶性渗漏）、膜脂过氧化、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性的变化。CV.威斯康星州38.后达到全叶扩展有一个快速的，几乎线性增加的86 Rb泄漏率从预装叶盘，叶龄。与此同时，膜通透性的增加是脂质过氧化水平的累积增加。在同一叶龄，SOD和过氧化氢酶活性也有变化。SOD活性的鲜重的基础上下降，但没有改变时，蛋白质含量的基础上测量可能是由于相对稳定的SOD在衰老相关的蛋白质含量的普遍下降。过氧化氢酶活性首先增加与叶绿素含量的叶片，然后，在充分的叶片扩展，鲜重和蛋白质含量的基础上下降。膜透性、膜脂过氧化和酶活性的变化与叶片蛋白质、叶绿素含量和叶绿素a：B比值的下降相一致。当衰老的最底部的叶子被逆转，从他们上面立即删除干，衰老相关的蛋白质和叶绿素含量，脂质过氧化和酶活性的变化被逆转。叶片衰老可能是由于膜脂过氧化水平的增加而引起的累积性膜劣化的结果，其中可能受SOD和过氧化氢酶活性的控制。
The changes in membrane permeability (soluble leakage), lipid peroxidation and activities of superoxide dismutase (SOD) and catalase were studied during in situ senescence of leaves of Nicotiana tabacum L., cv. Wisconsin 38. After full leaf expansion was reached there was a rapid, almost linear increase in the rate of 86Rb leakage from the preloaded leaf discs, with leaf age. Parallel with this increase in membrane permeability was a cumulative increase in the level of lipid peroxidation. At the same leaf age there were changes in the activities of SOD and catalase. SOD activity decreased on the basis of fresh weight but did not change when measured on the basis of protein content probably due to relative stability of SOD during the senescence-associated general decline in protein content. Catalase activity first increased parallel with the chlorophyll content of the leaf and then, after full leaf expansion, declined on the basis of both fresh weight and protein content. These changes in membrane permeability, lipid peroxidation and the enzyme activities coincide in leaf age with the decline in protein and chlorophyll contents and in chlorophyll a:b ratio. When the senescence of the bottom-most leaves was reversed by removing the stem from immediately above them, the senescence-associated changes in protein and chlorophyll contents, lipid peroxidation and the enzyme activities were reversed. Leaf senescence may be a consequence of cumulative membrane deterioration due to increasing level of lipid peroxidation probably controlled by, among other factors, the activities of SOD and catalase.