Regulation of maize catalase by changing rates of synthesis and degradation

Abstract

Rates of catalase synthesis and degradation were measured in the scutellum of the germinating maize seedling by the technique of Price, Sterling, Tarantola, Hartley & Rechcigl [J. Biol. Chem. (1963) 237, 3468-3475] by using the porphyrinogenic drug 2-allyl-2-isopropylacetamide to inhibit catalase synthesis. Results indicate that developmental changes in catalase activity are determined by changes in the rate of enzyme degradation as well as by changes in the rates of its synthesis.

Genetic regulation of the catalase developmental program in maize scutellum: Identification of a temporal regulatory gene

“…be obtained from the sum of net synthesis and degradation during the incubation period. The rate constants of synthesis (ks) and degradation (kd) were determined as described (22).…”

Evaluation of a catalase inhibitor in the developmental regulation of maize catalase

“…The slight increase in inhibitor protein observed at days two and three is coincident with two other aspects of catalase regulation in maize scutellum; increasing compartmentation in glyoxysomes [7] and a dramatic decrease in catalase degradation which occurs at this time [9] . It is possible that the catalase inhibitor may act in vivo in the catalase compartmentation process or may in some manner stabilize the catalase molecule by virtue of binding to it.…”

“…scutella without interfering with the germination process [9]. When catalase is kept at moderate levels by the AIA, inhibitor activity stays very high throughout (Fig.…”

Effect of elevated temperature on catalase and superoxide dismutase during maize development

“…The rates of CAT synthesis and degradation were determined using the CAT-synthesis inhibitor, AIA (N-allyl-Nisopropylacetamide [39]). Isolated scutella from seedlings of various ages were incubated at 25" or 40°C for 24 h in 0.2 il4 Na-acetate (pH 5.6) containing 0.08 M AIA, or in buffer alone.…”