碱胁迫下玉米microRNA827及其靶基因的表达响应

较高的pH影响植物根系对磷和氮的吸收，是盐碱土壤导致产量降低的主要原因之一。研究表明，植物在盐碱胁迫下microRNAs(miRNAs)通过调控靶基因的表达，提高植物对盐碱耐受性。通过实时定量RT-PCR分析表明，zma-miR827主要在冠根和花丝等组织中表达。碱胁迫处理玉米幼苗后，zma-miR827随着处理时间呈现先增加后降低趋势。通过玉米基因组数据库分析，预测zma-miR827-3p有4个靶基因，其中，GRMZM2G166976受碱胁迫后呈现先升高后持续下降的表达趋势；GRMZM2G077531则呈现先下降后升高；GRMZM2G127374呈现先下降后上升再下降后上升最后下降至最低值的趋势；GRMZM2G013176呈现持续升高的趋势。通过构建进化树分析表明，zma-miR827与水稻(Oryza sativa)中参与磷调控的osa-miR827高度同源。

Expression Response of Maize MicroRNA827 and the Target Genes under Alkali Stress

Higher pH affects the absorption of phosphorus and nitrogen by plant roots, which is one of the main reasons for the decrease of yield in saline soil. Studies have shown that plant microRNAs(miRNAs) can regulate the expression of target genes under saline-alkali stress to improve plant resistance. In this study, real-time quantitative RT-PCR analysis showed that zma-miR827 is mainly expressed in tissues such as crown roots and filaments. And after alkali stress treatment, zma-miR827 in maize seedlings showed a trend of first increasing and then decreasing with treatment time. Through the prediction and analysis of the maize genome database, it is predicted that zmamiR827-3p has 4 target genes. Among them, the target gene GRMZM2G166976 will first increase and then continue to decrease after being exposed to alkaline stress, while GRMZM2G077531 will first decrease and then increase, but GRMZM2G127374 presents a trend of first falling, then rising, then falling, then rising and finally falling to the lowest value. GRMZM2G013176 is showing a continuous rising trend. The phylogenetic tree analysis showed that zma-miR827 is highly homologous to osa-miR827, which is involved in phosphorus regulation in rice(Oryza sativa).