Department of Biology, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27514.
Plant Physiol. 1987 Jun;84(2):443-6. doi: 10.1104/pp.84.2.443.
Suspension cultures of carrot (Daucus carrota L.) which had an absolute requirement for exogenously supplied auxin were grown in medium containing indoleacetic acid (IAA) as the sole auxin source. Putative cell surface proteins were extracted from the intact cells. Resupply of IAA to cultures partially depleted of auxin resulted in rapidly increased activities of three enzyme activities subsequently extracted. Two of the enzyme activities which increased, peroxidase and pectinesterase, have been implicated in the literature as important to cell wall development, structure, and growth. The other enzyme activity which was increased, IAA oxidase, may be involved in the degradation of IAA In vivo. Polypeptides in the extracts were found to increase equally as rapidly as the enzymes in response to IAA as determined with sodium dodecyl sulfate-polyacrylamide electrophoretic gels stained with silver. It is not known whether the changes in enzyme and polypeptide levels in the protein extracts were due to auxin effects on protein synthesis, transport, or extractability.
悬浮培养的胡萝卜（Daucus carrota L.）对体外提供的生长素有绝对的需求，在含有吲哚乙酸（IAA）作为唯一生长素源的培养基中生长。从完整细胞中提取潜在的细胞表面蛋白。向部分耗尽生长素的培养液中再供应 IAA 会导致随后提取的三种酶活性迅速增加。文献中提到，两种增加的酶活性（过氧化物酶和果胶酯酶）对细胞壁的发育、结构和生长很重要。另一种增加的酶活性（IAA 氧化酶）可能参与 IAA 的体内降解。用银染色的十二烷基硫酸钠-聚丙烯酰胺电泳凝胶测定，提取物中的多肽与酶一样，对 IAA 的反应同样迅速增加。尚不清楚蛋白质提取物中酶和多肽水平的变化是由于生长素对蛋白质合成、运输或可提取性的影响。
