[Show abstract][Hide abstract] ABSTRACT: Five enzymes involved in the generation and scavenging of reactive oxygen species, i.e., NADH/NADPH oxidase, xanthine oxidase (XOD), superoxide dismutase (SOD), ascorbate peroxidase, and catalase were assayed in various tissues of the Japanese monkey. Their activities were largely different between tissues. Generally, small intestine, kidney, and cerebellum contained larger amounts of these enzymes than other tissues. Multiplicities of these enzymes were analyzed by staining of their enzymatic activities after electrophoresis. The number of isozymes was 2 in the case of NADPH oxidase and catalase, and 3 in the case of XOD, SOD, and ascorbate peroxidase. The expression of these isozymes differed between tissues, suggesting the occurrence of tissue-specific systems to generate and scavenge reactive oxygen species in the Japanese monkey.
[Show abstract][Hide abstract] ABSTRACT: The mechanism of self incompatibility in pistils of Lilium longiflorum Thunb. cv. Hinomoto, which is overcome by heat treatment, was analyzed. Immersing detached pistils in a distilled water bath
held at 45°C for 5 min suppressed levels of ethylene and activities of 1-aminocyclopropane-1-carboxylate (ACC) oxidase at
6 h after self- and cross-incompatible pollination. However, the levels and activities showed no significant difference 48
h after pollination. Levels of ACC and activities of ACC synthase at 6 h after self-incompatible pollination were lower in
pistils with heat treatment. Moreover, the heat treatment suppressed the activity of superoxide dismutase and enhanced the
activity of catalase, ascorbate peroxidase, dehydroascorbate reductase, and glutathione reductase. In addition, the amount
of hydrogen peroxide (H2O2) was reduced by heat treatment. In summary, heat treatment suppressed the ethylene-forming system and also enhanced the hydrogen
peroxide-scavenging system in self-pollinated pistils associated with self incompatibility. A possible correlation between
self incompatibility and stress in pistils after self-incompatible pollination is discussed based on the results obtained
using heated pistils.
Sexual Plant Reproduction 01/2001; 13(4):201-208. · 2.07 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: An attempt was made to examine the possible connection between self-incompatibility in Lilium longiflorum and the stress response using pistils after self-incompatible pollination. The growth of pollen tubes in the pistil after self-incompatible pollination was promoted by treatment with germanium compounds [(GeCH 2 CH 2 COOH) 2 O 3 and GeO 2 ], which are scavengers of active oxygen species, such as O 2 − and H 2 O 2 . The promotion by germanium compounds of the growth of pollen tubes after self-incompatible pollination was reflected by the detection of elevated levels of activity of superoxide-forming NADPH-dependent oxidase, xanthine oxidase, superoxide dismutase, catalase and ascorbate peroxidase, all of which are associated with stress responses, in pistils upon self-incompatible pollination as compared to the activities of these enzymes after cross-compatible pollination. A possible connection between self-incompatibility and stress in pistils upon self-incompatible pollination is discussed on the basis of these results.