Chen C M, Ertl J R, Leisner S M, Chang C C
Biomedical Research Institute, University of Wisconsin-Parkside, Kenosha, Wisconsin 53141.
Plant Physiol. 1985 Jul;78(3):510-3. doi: 10.1104/pp.78.3.510.
The biosynthesis of cytokinins was examined in pea (Pisum sativum L.) plant organs and carrot (Daucus carota L.) root tissues. When pea roots, stems, and leaves were grown separately for three weeks on a culture medium containing [8-(14)C]adenine without an exogenous supply of cytokinin and auxin, radioactive cytokinins were synthesized by each of these organs. Incubation of carrot root cambium and noncambium tissues for three days in a liquid culture medium containing [8-(14)C]adenine without cytokinin demonstrates that radioactive cytokinins were synthesized in the cambium but not in the noncambium tissue preparation. The radioactive cytokinins extracted from each of these tissues were analyzed by Sephadex LH-20 columns, reverse phase high pressure liquid chromatography, paper chromatography in various solvent systems, and paper electrophoresis. The main species of cytokinins detectable by these methods are N(6)-(Delta(2)-isopentyl_adenine-5'-monophosphate, 6-(4-hydroxy-3-methyl-2-butenyl-amino)-9-beta-ribofuranosylpurine-5'- monophosphate, N(6)-(Delta(2)-isopentenyl)adenosine, 6-(4-hydroxy-3-methyl-2-butenylamino)-9-beta-ribofuranosylpurine, N(6)-(Delta(2)-isopentenyl)adenine, and 6-(4-hydroxy-3-methyl-2-butenylamino)purine. On the basis of the amounts of cytokinin synthesized per gram fresh tissues, these results indicate that the root is the major site, but not the only site, of cytokinin biosynthesis. Furthermore, cambium and possibly all actively dividing tissues are responsible for the synthesis of this group of plant hormones.
对豌豆（Pisum sativum L.）植株器官和胡萝卜（Daucus carota L.）根组织中的细胞分裂素生物合成进行了研究。当豌豆根、茎和叶在不含外源细胞分裂素和生长素但含有[8-(14)C]腺嘌呤的培养基上分别培养三周时，这些器官各自都合成了放射性细胞分裂素。将胡萝卜根形成层和非形成层组织在不含细胞分裂素但含有[8-(14)C]腺嘌呤的液体培养基中培养三天，结果表明放射性细胞分裂素是在形成层中合成的，而非形成层组织提取物中未合成。从这些组织中提取的放射性细胞分裂素通过葡聚糖LH - 20柱、反相高压液相色谱、多种溶剂系统中的纸色谱以及纸电泳进行分析。通过这些方法可检测到的主要细胞分裂素种类有N(6)-(Δ(2)-异戊烯基)腺嘌呤-5'-单磷酸、6-(4-羟基-3-甲基-2-丁烯基氨基)-9-β-呋喃核糖基嘌呤-5'-单磷酸、N(6)-(Δ(2)-异戊烯基)腺苷、6-(4-羟基-3-甲基-2-丁烯基氨基)-9-β-呋喃核糖基嘌呤、N(6)-(Δ(2)-异戊烯基)腺嘌呤以及6-(4-羟基-3-甲基-2-丁烯基氨基)嘌呤。基于每克新鲜组织合成的细胞分裂素量，这些结果表明根是细胞分裂素生物合成的主要部位，但不是唯一部位。此外，形成层以及可能所有活跃分裂的组织都负责这类植物激素的合成。
