ISOLATION AND CHARACTERIZATION OF THE GENES ENCODING BASIC AND ACIDIC CHITINASE IN ARABIDOPSIS-THALIANA
ISOLATION AND CHARACTERIZATION OF THE GENES ENCODING BASIC AND ACIDIC CHITINASE IN ARABIDOPSIS-THALIANA
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DOI：
10.1104/pp.93.3.907
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发表时间：
1990-07-01
期刊：
影响因子：
7.4
通讯作者：
SHAH, DM
中科院分区：
文献类型：
--
作者：
SAMAC, DA;HIRONAKA, CM;SHAH, DM
植物在病原菌入侵和环境胁迫下合成大量的抗菌蛋白。这些蛋白质包括两类几丁质酶，其具有碱性或酸性等电点并且能够降解真菌细胞壁几丁质。本研究克隆了拟南芥（Arabidopsis thaliana（L.）嘿哥伦比亚野生型。这两种几丁质酶都由含有内含子的单拷贝基因编码，这是几丁质酶基因的一个新特征。碱性几丁质酶与烟草碱性几丁质酶的氨基酸序列相似性为73%，酸性几丁质酶与黄瓜酸性几丁质酶的氨基酸序列相似性为60%。在拟南芥中，基本几丁质酶的表达具有器官特异性和年龄依赖性。在根中观察到高组成型表达水平，而在叶和开花枝中观察到较低水平。植物暴露于乙烯诱导高水平的系统表达的基本几丁质酶的表达与植物年龄增加。在拟南芥乙烯不敏感突变体etr的根中观察到碱性几丁质酶的组成型表达，表明根特异性表达是乙烯非依赖性的。酸性几丁质酶基因的表达没有观察到在正常的，未经处理的拟南芥植物或在植物乙烯或水杨酸处理。然而，瞬时表达试验表明酸性几丁质酶启动子在拟南芥叶组织中是有活性的。
Plants synthesize a number of antimicrobial proteins in response to pathogen invasion and environmental stresses. These proteins include two classes of chitinases that have either basic or acidic isoelectric points and that are capable of degrading fungal cell wall chitin. We have cloned and determined the nucleotide sequence of the genes encoding the acidic and basic chitinases from Arabidopsis thaliana (L.) Heynh. Columbia wild type. Both chitinases are encoded by single copy genes that contain introns, a novel feature in chitinase genes. The basic chitinase has 73% amino acid sequence similarity to the basic chitinase from tobacco, and the acidic chitinase has 60% amino acid sequence similarity to the acidic chitinase from cucumber. Expression of the basic chitinase is organ-specific and age-dependent in Arabidopsis. A high constitutive level of expression was observed in roots with lower levels in leaves and flowering shoots. Exposure of plants to ethylene induced high levels of systemic expression of basic chitinase with expression increasing with plant age. Constitutive expression of basic chitinase was observed in roots of the ethylene insensitive mutant (etr) of Arabidopsis, demonstrating that root-specific expression is ethylene independent. Expression of the acidic chitinase gene was not observed in normal, untreated Arabidopsis plants or in plants treated with ethylene or salicylate. However, a transient expression assay indicated that the acidic chitinase promoter is active in Arabidopsis leaf tissue.