甜瓜中甜菜碱醛脱氢酶基因CmBADH的克隆及非生物胁迫下的表达分析

Cloning and Expression Analyzing of One BADH Gene CmBADH of Muskmelon Under Abiotic Stress

以甜瓜(Cucumis melo L.)‘TS-2’为材料,根据GenBank登录的植物甜菜碱醛脱氢酶氨基酸保守序列设计兼并引物,利用RT-PCR和3′、5′RACE技术从甜瓜叶片中克隆到1个甜菜碱醛脱氢酶基因,命名为CmBADH,在GenBank中的注册号为:JN091961.1。生物信息学分析表明,该基因全长1856bp,编码503个氨基酸,BADH蛋白大小约54kD,理论pI为5.182。甜瓜BADH蛋白与麻疯树同源性最高,为82.96%。该基因编码蛋白有4个强的跨膜螺旋结构。PlantCare分析结果显示该基因序列具有茉莉酸甲酯、防御与胁迫、玉米醇蛋白代谢途径、低温、光响应、分生组织表达、生理周期调控等顺式作用元件和干旱诱导的MYB结合位点。实时荧光定量PCR表明,CmBADH受盐、干旱、低温、高温诱导,其表达均呈现先上升后下降的趋势;CmBADH还随外源ABA诱导时间的延长呈现上升表达的趋势。

The muskmelon （Cucumis melo L. ）of TS-2 was used as experimental materials, using PCR degenerate primers designed based on the conserved amino acid sequences of known betaine aldehyde dehydrogenase to amplify eDNA fragments from muskmelon by RT-PCR and 3＇, 5＇RACE, a BADH gene named CmBADH was cloned and the registration number in GenBank is JN091961.1. Bioinformatics analysis indicated that the full length sequence ofBADHwas 1 856 bp, encoding 503 amino acids residues with a calculated molecular weight of 54 kD and isoelectric point of 5.182. The BADH protein in muskmelon showed the highest similarity with from Jatropha curcas, and the similarity was 82.96%. There were four strong inside to outside transmembrane helixes. PlantCare analysis indicated that there were cis-acting responsive elements of MeJA-responsiveness, defense and stress, zein metabolism regulation, low-temperature, light responsiveness, meristem expression, and circadian control as well asMYB binding site involved in drought-inducibility. The result of RT-PCR analysis indicated that the expression of CmBADH is induced by salt stress, drought stress, low temperature and high temperature stress, and its expression trend increased firstly and then decreased the expression of CmBADH was also induced by ABA treatment.