Lee T T
Research Institute, Research Branch, Canada Department of Agriculture, University Sub Post Office, London 72, Ontario, Canada.
Plant Physiol. 1971 Feb;47(2):181-5. doi: 10.1104/pp.47.2.181.
Indoleacetic acid oxidase in tobacco callus tissues (Nicotiana tabacum L., cultivar White Gold) was resolved into seven anionic isoenzymes by polyacrylamide gel disc electrophoresis. Different concentrations of kinetin and zeatin in the presence of indoleacetic acid affected the level of this enzyme, particularly two fast-moving isoenzymes, A(5) and A(6). The optimal concentration of kinetin was 0.2 mum; increasing concentrations above this level progressively lowered the total activity of indoleacetic acid oxidase and repressed the development of isoenzymes A(5) and A(6). Actinomycin D and cycloheximide inhibited the development of these two isoenzymes under the influence of 0.2 mum kinetin, suggesting a requirement for RNA and protein synthesis. The cytokinin-promoted indoleacetic acid oxidase isoenzymes A(5) and A(6) increased with time and paralleled the dry weight increase of tobacco callus tissues, but the total activity of indoleacetic acid oxidase per unit dry weight of tobacco callus varied with time depending on the stage of plant growth.
通过聚丙烯酰胺凝胶圆盘电泳，烟草愈伤组织（烟草品种白金）中的吲哚乙酸氧化酶被分离为七种阴离子同工酶。在吲哚乙酸存在的情况下，不同浓度的激动素和玉米素会影响这种酶的水平，尤其是两种迁移速度较快的同工酶A(5)和A(6)。激动素的最佳浓度为0.2 μmol；高于此水平的浓度增加会逐渐降低吲哚乙酸氧化酶的总活性，并抑制同工酶A(5)和A(6)的发育。放线菌素D和环己酰亚胺在0.2 μmol激动素的影响下抑制了这两种同工酶的发育，表明需要RNA和蛋白质合成。细胞分裂素促进的吲哚乙酸氧化酶同工酶A(5)和A(6)随时间增加，并与烟草愈伤组织的干重增加平行，但每单位烟草愈伤组织干重的吲哚乙酸氧化酶总活性随时间变化，这取决于植物生长阶段。
