摘要
AP2/ERF是广泛存在于植物中一类重要的转录因子,调控一些参与非生物胁迫相关基因的表达,帮助植物提高逆境胁迫能力。为了深入探讨LaAP2在独行菜耐受低温萌发及幼苗耐受低温生长中的功能,该研究基于前期对独行菜(Lepidium apetalum)转录组数据库分析,克隆获得一个显著上调表达的AP2/ERF家族序列LaAP2。该基因cDNA全长为1 005 bp,编码氨基酸序列包含一个AP2和一个B3结构域,属于AP2/ERF转录因子RAV亚家族。推定的LaAP2蛋白分子量为37.744 67 kD,等电点为9.49。该蛋白氨基酸序列同亚麻荠、拟南芥、油菜等物种显示出较高同源性,系统进化分析结果表明与拟南芥亲缘关系较近。氨基酸序列分析预测表明,LaAP2基因所编码的蛋白不具备信号肽区段,无跨膜区,不属于分泌蛋白,可能为亲水性蛋白;定位于细胞质的可能性为56.5%,定位于细胞核的可能性为21.7%;其主要二级结构元件为无规则卷曲、延伸链、α-螺旋。Real-time PCR分析独行菜幼苗中LaAP2在低温4℃处理下的表达,显示LaAP2表达受低温胁迫呈先下降后升高趋势。这表明LaAP2在独行菜幼苗抵抗低温胁迫中起调控作用。
AP2/ ERF is a kind of important transcription factors widely existing in plants. AP2/ ERF regulate the expressionof some genes involved in abiotic stress, and help plants improve the ability of adversity stress. We obtained a gene LaAP2by cloning a significantly up-regulated expression AP2/ ERF family gene sequence by RT-PCR technology, based on theprevious analysis of Lepidium apetalum transcriptome database. Bioinformatics analysis of LaAP2 encoded amino acid se-quence composition, physical and chemical properties, structure, hydrophobicity, transmembrane region, signal peptide,subcellular localization and secondary protein structure. Real-time PCR was used to detect the expression of LaAP2 gene at4 ℃ low temperature stress. The result showed that the full-length cDNA of the gene was 1 005 bp, and the encoded aminoacid sequence contains a AP2 and a B3 domain, belonging to the AP2/ ERF transcription factor RAV subfamily. The mole-cular weight of putative LaAP2 protein was 37.744 67 kD and the isoelectric point was 9.49. The amino acid sequence hashigh homology with Camelina sativa, Arabidopsis thaliana and rape. Phylogenetic analysis showed that the genetic relation-ship was close to that of A. thaliana. The amino acid sequence analysis showed that LaAP2 gene encoding protein had nosignal peptide segments, no transmembrane region, did not belong to the secreted protein. It could be the hydrophilic pro-tein. The possibility of localization in cytoplasm was 56.5%, and in nucleus was 21.7%. The main structural elements wererandom coil, extending strand and alpha helix. We analyzed the expression of AP2/ ERF gene in Lepidium apetalum seed-lings under 4 ℃ low temperature stress through Real-time PCR technology, which showed that LaAP2 gene expression wasdecreased firstly and then increased. The results suggest that LaAP2 play a role in regulating the resistance of low tempera-ture stress in Lepidieae seedling. This study lays the foundation for further study on the function of LaAP2 on the L. apeta-lum seed germination and seedling growth in tolerance to low temperature.
作者
李艳红
曾卫军
李金玉
葛风伟
朱艳蕾
赵惠新
LI Yanhong;ZENG Weijun;LI Jinyu;GE Fengwei;ZHU Yanlei;ZHAO Huixin(Xinjiang Key Laboratory of Special Species Conservation and Regulatory Biology,Key Laboratory of Plant Stress Biologyin Arid Land,College of Life Sciences,Xinjiang Normal University,Urumqi 830054,Chin)
出处
《广西植物》
CAS
CSCD
北大核心
2018年第6期762-770,共9页
Guihaia
基金
国家自然科学基金(31460041,31660079)
新疆维吾尔自治区高校科研计划科学研究重点项目(XJEDU2014I027)
新疆维吾尔自治区教育厅重点实验室项目(新疆特殊环境物种多样性应用与调控重点实验室)
新疆师范大学“十三五”校级重点学科生物学学科项目
作者简介
李艳红（1981-）,女,山东潍坊人,博士,讲师,研究方向为植物逆境生理生化与分子生物学,（E-mail）496917835＠qq.com.;通信作者：赵惠新,博士,副教授,研究方向为植物逆境生理生化与分子生物学,（E-mail）zhaohuixin101＠sina.com.
