芹菜AgERF4转录因子基因的克隆与表达分析

Cloning and Expression Profile Analysis of AgERF4 Transcription Factor Gene from Apium graveolens

以‘六合黄心芹’芹菜为材料,克隆出编码乙烯反应元件结合蛋白基因AgERF4。序列分析表明,AgERF4含有1个长度为597 bp的开放阅读框,编码198个氨基酸,预测其蛋白质相对分子质量为21.43 kD,等电点为8.51。进化分析表明,ERF4转录因子在植物中高度保守。AgERF4属于亲水性蛋白。酵母单杂交和β–半乳糖苷酶活性测定结果确定AgERF4转录因子和乙烯应答元件GCC Box具有较高的结合活性。RT-qPCR分析表明,AgERF4在芹菜叶片中的表达水平较高,在根和叶柄中表达水平较低;高温和干旱条件下AgERF4的表达呈先上升后下降的趋势,在盐处理的24 h内AgERF4的表达始终高于对照。AgERF4转录因子在芹菜非生物逆境胁迫调控过程中起着重要作用。

In this study, the AgERF4 gene was cloned from celery variety ＇Liuhehuangxinqin＇ . Sequence analysis indicated that the length ofAgERF4 gene was 597 bp, which encoded 198 amino acids. It is predicted that the molecular mass of its protein was 21.43 kD, and pI was 8.51. Phylogenetic analysis indicated that the ERF4 showed high evolutionary conservation among celery and other species. The AgERF4 belongs to hydrophilic protein. Yeast one-hybrid and fl-galactosidase activity assays confirmed the GCC box-binding activities of AgERF4 factor. RT-qPCR analysis demonstrated that the AgERF4 gene was mainly expressed in leaf blade. The expression profiles of the AgERF4 gene in root and petiole have no significant difference. When exposed to high or low temperature treatments, the expression level of AgERF4 gene showed an increased trend at first, followed by a reduction. Under salt treatments, the transcription of AgERF4 was higher than that of the control. The results suggested that AgERF4 factor may play important roles in the defense response to abiotic stress in celery.