Ohl S, Hedrick S A, Chory J, Lamb C J
Plant Biology Laboratory, Salk Institute for Biological Studies, La Jolla, California 92037.
Plant Cell. 1990 Sep;2(9):837-48. doi: 10.1105/tpc.2.9.837.
Phenylalanine ammonia-lyase (PAL) is encoded by a small family of genes in Arabidopsis. We cloned and partially characterized one of these genes, PAL1. The deduced amino acid sequence is highly similar to PAL from bean, parsley, and rice. The promoter contains sequence elements homologous to two putative regulatory elements conserved among several phenylpropanoid genes. The regulation of the PAL1 gene was examined by analysis of beta-glucuronidase (GUS) activity in transgenic Arabidopsis containing PAL1-GUS gene fusions. The PAL1 promoter was activated early in seedling development and in adult plants was strongly expressed in the vascular tissues of roots and leaves, but was not active in the root tip or the shoot apical meristem. In flowers, expression was observed in sepals, anthers, and carpels, but not in petals. Transcripts encoded by the endogenous PAL genes and GUS transcripts from the PAL1-GUS gene fusion were induced by wounding, HgCl2-stress, and light. Analysis of the regulatory properties of 5' deleted promoters showed that the proximal region of the promoter to -290 was sufficient to establish the full tissue-specific pattern of expression and that the proximal region to -540 was responsive to environmental stimuli. Negative and positive elements were located between -1816 and -823 and between -823 and -290, respectively.
苯丙氨酸解氨酶（PAL）由拟南芥中的一个小基因家族编码。我们克隆并部分鉴定了其中一个基因PAL1。推导的氨基酸序列与来自菜豆、欧芹和水稻的PAL高度相似。该启动子包含与几个苯丙烷类基因中保守的两个假定调控元件同源的序列元件。通过分析含有PAL1-GUS基因融合体的转基因拟南芥中的β-葡萄糖醛酸酶（GUS）活性，研究了PAL1基因的调控。PAL1启动子在幼苗发育早期被激活，在成年植物中，在根和叶的维管组织中强烈表达，但在根尖或茎尖分生组织中不活跃。在花中，在萼片、花药和心皮中观察到表达，但在花瓣中不表达。内源性PAL基因编码的转录本和PAL1-GUS基因融合体的GUS转录本受到创伤、HgCl2胁迫和光照的诱导。对5'缺失启动子调控特性的分析表明，启动子至-29０的近端区域足以建立完整的组织特异性表达模式，而至-540的近端区域对环境刺激有反应。负调控元件和正调控元件分别位于-1816至-823和-823至-290之间。
