Caboche M, Muller J F, Chanut F, Aranda G, Cirakoglu S
Laboratoire de Biologie cellulaire, Institut National de la Recherche Agronomique, 78000 Versailles, France.
Plant Physiol. 1987 Apr;83(4):795-800. doi: 10.1104/pp.83.4.795.
A naphthaleneacetic acid tolerant mutant isolated from a mutagenized culture of tobacco mesophyll protoplasts and impaired in root morphogenesis has been previously characterized by genetic analysis. To understand the biochemical basis for naphthaleneacetic acid resistance, cells derived from this mutant and from wild-type tobacco were compared for their ability to respond to various growth regulators. The growth promoting abilities and cytotoxicities of auxin analogs were different for mutant and wild-type cells. These different activities were not correlated with increased rate of conjugation or breakdown of the auxins by mutant cells. These observations, as well as previous studies on the interaction of the mutant with Agrobacterium, suggest that mutant resistance to auxins is not a result of a specific modification of the process by which auxins induce cell killing, but to a more general alteration of the cellular response to auxin. A screening of auxin-related molecules which induce cell death in wild-type cells but not mutant cells without promoting growth in either was performed. p-Bromophenyleacetic acid was found to display these characteristics.
先前已通过遗传分析对从诱变的烟草叶肉原生质体培养物中分离出的、在根形态发生方面受损的萘乙酸耐受性突变体进行了表征。为了了解萘乙酸抗性的生化基础，比较了源自该突变体和野生型烟草的细胞对各种生长调节剂的反应能力。生长素类似物对突变体细胞和野生型细胞的促生长能力及细胞毒性不同。这些不同的活性与突变体细胞中生长素结合或分解速率的增加无关。这些观察结果以及先前关于该突变体与农杆菌相互作用的研究表明，突变体对生长素的抗性不是生长素诱导细胞死亡过程发生特定修饰的结果，而是细胞对生长素反应的更普遍改变。进行了一项筛选，寻找在野生型细胞中诱导细胞死亡但在突变体细胞中不诱导细胞死亡且在两者中均不促进生长的生长素相关分子。发现对溴苯乙酸具有这些特性。
