After salt stress, the sensitivitytoward the inhibitory action of L-malateof PEPCase from Mesembryanthemum cordifolium showed diurnal fluctuation(Fig. 1a, b). The day form PEPCasewas more sensitive to the inhibition b...After salt stress, the sensitivitytoward the inhibitory action of L-malateof PEPCase from Mesembryanthemum cordifolium showed diurnal fluctuation(Fig. 1a, b). The day form PEPCasewas more sensitive to the inhibition byL-malate than the night form (Fig.fo). However, there was no differencein molecular weight between the dayform and the night form of PEPCase(Fig. 2). Both salt stress and droughtelevated the leaf ABA level dramatically (Fig. 3A ). The ABA level indrought-stressed leaves decreasedmarkedly after the plants were rewatered (Fig. 3A), but the ABA level insalt-stressed leaves remained unchangedafter soil salts were thoroughly washedout and the plants were well watered(Fig. 3A). External ABA treatment increased the leaf PEPChse activity anddecreased the leaf water content (Fig.3B). Externally applied 6-BA had similar effects on the plants as the ABA(Fig. 4 ). We concluded that: 1. Theday/night difference in the regulatoryaction of CAM form PEPCase was notcaused by any change in the saute of aggregation of the enzyme; 2. The effectSo f ABA and 6-BA on leaf PEPCase level are most likely mediated by leaf water loss they induced.展开更多
Abstract Melatonin （N-acetyi-5-methoxytryptamine） is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has ...Abstract Melatonin （N-acetyi-5-methoxytryptamine） is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has been observed that melatonin is widely existed in higher plants while there have no enough studies on functions of melatonin in plants. Researches have already indicated that the possible functions of melatonin in plants include regulating photoperiod, participating in growth regulation, clearing active oxygen, and promoting activity of antioxidase. General reviews upon functions of melatonin in plants are made upon experiments in recent years. We fo-cus on the demonstrated and predicted biological functions of melatonin in plants to bring researchers up to date on this field. The weakness in present studies and the main research directions are also pointed out.展开更多
文摘After salt stress, the sensitivitytoward the inhibitory action of L-malateof PEPCase from Mesembryanthemum cordifolium showed diurnal fluctuation(Fig. 1a, b). The day form PEPCasewas more sensitive to the inhibition byL-malate than the night form (Fig.fo). However, there was no differencein molecular weight between the dayform and the night form of PEPCase(Fig. 2). Both salt stress and droughtelevated the leaf ABA level dramatically (Fig. 3A ). The ABA level indrought-stressed leaves decreasedmarkedly after the plants were rewatered (Fig. 3A), but the ABA level insalt-stressed leaves remained unchangedafter soil salts were thoroughly washedout and the plants were well watered(Fig. 3A). External ABA treatment increased the leaf PEPChse activity anddecreased the leaf water content (Fig.3B). Externally applied 6-BA had similar effects on the plants as the ABA(Fig. 4 ). We concluded that: 1. Theday/night difference in the regulatoryaction of CAM form PEPCase was notcaused by any change in the saute of aggregation of the enzyme; 2. The effectSo f ABA and 6-BA on leaf PEPCase level are most likely mediated by leaf water loss they induced.
基金Supported by National 863 Project of China(2012AA101801)"Twelfth Five-Year"Plan for Science&Technology Project(2011BAD17B01)Chinese Universities Scientific Fund(2009-2-06)~~
文摘Abstract Melatonin （N-acetyi-5-methoxytryptamine） is a well-known animal hormone, which is synthesized and secreted by pineal gland and takes part in the regulation of circadian rhythm in animals. At present it has been observed that melatonin is widely existed in higher plants while there have no enough studies on functions of melatonin in plants. Researches have already indicated that the possible functions of melatonin in plants include regulating photoperiod, participating in growth regulation, clearing active oxygen, and promoting activity of antioxidase. General reviews upon functions of melatonin in plants are made upon experiments in recent years. We fo-cus on the demonstrated and predicted biological functions of melatonin in plants to bring researchers up to date on this field. The weakness in present studies and the main research directions are also pointed out.
