玉米生长素响应因子基因家族全基因组鉴定及表达分析

生长素响应因子(ARF)在植物中可以特异性结合在应答基因的启动子区域,调控植物的生长发育。为了进一步了解玉米ARF基因家族的数量、基本特征、进化关系及响应非生物胁迫和激素的表达模式,本研究在全基因组水平,通过生物信息学方法鉴定玉米ARF基因家族,分析了蛋白理化性质及系统发育,利用实时荧光定量PCR(RT-qPCR)分析了4个ZmARFs基因的时空表达模式及高温、干旱、盐和脱落酸(ABA)处理下的表达情况。结果表明,玉米36个ARFs基因随机非均匀分布在9条染色体上,编码氨基酸长度、分子量、等电点及二级结构存在很大的差异。高粱、水稻、拟南芥和玉米的蛋白复合进化树显示共分为Ⅰ~Ⅳ四大类,玉米与高粱ARF蛋白亲缘关系最近,而与拟南芥ARF蛋白亲缘关系最远,且玉米中发生基因内和基因间复制现象。启动子顺式作用元件主要是干旱、低温、氧化和激素类响应元件。RT-qPCR结果显示,ZmARF1、ZmARF6、ZmARF13和ZmARF22基因均在雄穗分支和胚中表达量较高,在花粉中表达量较低;4个基因(除ZmARF22)在高温、干旱、盐和ABA诱导时均显著上调表达。亚细胞定位表明上述4个基因编码的蛋白质均定位于细胞核。本研究结果为揭示玉米ARF蛋白功能和挖掘玉米的抗逆基因提供了理论基础,为抗逆育种提供了分子资源。

Geneome-Wide Identification and Expression Analysis of Auxin Response Factor Gene Family in Maize

Auxin response factor (ARF) can specifically bind to the promoter region of response gene to regulate plant growth and development. In order to understand furtherly the number, basic characteristics, evolutionary relationship of ARF gene family in maize and the expression pattern of ARF in response to abiotic stress and hormone. In this study, the ARF gene family in maize was identified by bioinformatics, and the physiochemical properties and the phylogeny of proteins were analyzed. RT-qPCR was used to analyze the temporal and spatial expression patterns and their expression under high temperature, drought, salt and ABA treatment of fourZmARFs. The results showed that 36 ARFs genes were randomly and unevenly distributed on 9 chromosomes, and the amino acid length, molecular weight, isoelectric point and secondary structure of the encoding protein were quite different. The protein phylogenetic tree of sorghum, rice, Arabidopsis and maize showed that these ARF proteins are divided into four categories Ⅰ~Ⅳ. Maize ARF has the closest genetic relationship with sorghum ARF, and the farthest genetic relationship with Arabidopsis ARF, and there were intragenic and intergenic duplication occurs in maize.The cis-acting elements of promoter are main elements in response to drought, low temperature, oxidation and hormones. RT-qPCR results showed that the expression of ZmARF1,ZmARF6,ZmARF13 and ZmARF22 were higher in the tassel branches and embryos, but lower in the pollen. The four genes were significantly up-regulated when induced by high temperature, drought, salt and ABA, except that ZmARF22 gene had decreased expression after high temperature treatment. Subcellular localization indicated that the proteins encoded byZmARF1, ZmARF6, ZmARF13 and ZmARF22 are localized in the nucleus. The results of this study provide a theoretical basis for revealing the function of maize ARF protein and mining stress resistant genes, and also provide molecular resources for stress resistant breeding.