西瓜BADH基因序列分析及其乙烯和茉莉酸甲酯诱导表达特性  

Sequence Analysis of BADH Gene and Expression Characteristics Induced by Ethylene and Methyl Jasmonate in Watermelon

作　　者：徐子健[1] 孙梦利 龙娅丽 乔飞[2] 党选民[2] 江雪飞[1] 

机构地区：[1]海南省热带生物资源可持续利用重点实验室(省部共建国家重点实验室培育基地),海南大学热带农林学院,海口570228 [2]中国热带农业科学院热带作物品种资源研究所,农业部华南作物基因资源与种质创制重点开放实验室,儋州571737

出　　处：《分子植物育种》2017年第4期1218-1225,共8页Molecular Plant Breeding

基　　金：海南省自然科学基金项目(20153059);海南大学中西部计划学科建设项目(ZXBJH-XK008);中国热带农业科学院基本科研业务费专项基金(1630052016006)共同资助

摘　　要：甜菜碱作为植物体内一种重要的渗透调节物,对调节逆境下植物细胞的渗透压起着十分重要的作用,而甜菜碱醛脱氢酶(BADH)在植物甜菜碱合成过程中起了关键的催化作用。本研究中,通过分析西瓜BADH基因的结构和功能,结果表明:ClBADH基因启动子区结构中含有15个外显子和14个内含子,其含有包括乙烯响应元件在内的20多种顺式响应元件;ClBADH基因编码的蛋白含有503个氨基酸,该蛋白分子量约为54.5 kD;蛋白亚细胞定位预测显示其可能定位在细胞质中,具有氧化还原酶活性。通过对系统进化树的分析发现西瓜在同源关系上与同科的黄瓜和甜瓜更近,而与藜科的甜菜的同源关系相对较远。此外,以茉莉酸甲酯和乙烯两种物质模拟逆境信号处理西瓜细胞,发现两种信号物质诱导后,西瓜ClBADH基因的表达量均有上调的趋势,但其上调的速度和幅度却存在明显的差异。本研究为通过逆境信号诱导提高西瓜抗逆性提供参考,也为利用基因工程技术提高西瓜抗逆性提供支持。Betaine is an important osmoregulation substance in plants, which plays very important roles in regulating osmotic pressure of plant cells under stress. Betaine aldehyde dehydrogenase （BADH） is one of the key enzymes in the synthesis of betaine. Analysis of the structure and function of BA DH gene in watermelon showed that ClBADH gene contains 14 introns and 15 exons; Its transcription start site was located at 210 bp upstream from the start eodon and this gene had more than 20 CIS response elements including ethylene-response elements; ClBADH gene encoded a protein containing 503 amino acids, and its molecular weight was 54.5 kD; This protein may be localized in the cytoplasm with a redox enzyme activity. The phylogenetic tree indicate that BA DH gene of watermelon was closer to cucumber and melon in the homologous relationship and relatively far with beet. Moreover, expression of ClBADH gene in watermelon cells after challenged by methyl jasmonate and ethylene showed the expression level increased after the induction, but the rate of expression and the amplitude were significantly different between these two different signal substances. This study provided supports on resistance induction by elicitors and also shed some light on improving the resistance of watermelon by genetic engineering technology.

关 键 词：西瓜 BADH基因 乙烯 茉莉酸甲酯 表达分析 

分 类 号：Q943.2[生物学—植物学] S651[农业科学—果树学]