Abstract: The ear-leaf samples collected from Zhengdan 309 under normal condition(CK) and high temperature stress for 7 d and 14 d were used for RNA-sequencing using Illumina HiSeqTM2500 high-throughput sequencing technology and metabolome profiling analysis using liquid-chromatographymass spectrometry-based metabolomics. Differentially expressed genes (DEGs) and metabolites were explored to clarify the mechanism of maize responding to high temperature stress at the anthesis stage.The transcriptome sequencing results showed that 515 DEGs were detected in Zhengdan 309 under high temperature stress for 7 d compared with the control under normal growth condition, of which 75 genes were up-regulated,and 440 genes were down-regulated.There were 506 DEGs detected in Zhengdan 309 under high temperature stress for 14 d compared with the control under normal growth condition,including 114 up-regulated genes and 392 down-regulated genes. There were 2 050 DEGs detected in Zhengdan 309 under high temperature stress for 7 d compared with that under high temperature stress for 14 d, of which 790 genes were up-regulated,and 1 260 genes were down-regulated. The DEGs in Zhengdan 309 under high temperature stress for 7 d compared with that under the normal condition were concentrated in extracelluar region, molecular function regulator and other GO classification.The DEGs in Zhengdan 309 under high temperature stress for 14 d compared with that under the normal condition were mainly enriched in rhythmic process, extracelluar region and other GO classification.The DEGs in Zhengdan 309 under high temperature stress for 7 d compared with that under high temperature stress for 14 d were mainly enriched in cell part, single-organism process and other GO classification.The DEGs in Zhengdan 309 under high temperature stress for 7 d compared with that under the normal condition,Zhengdan 309 under high temperature stress for 14 d compared with that under the normal condition and Zhengdan 309 under high temperature stress for 7 d compared with that under high temperature stress for 14 d were mainly distributed in 5, 7 and 15 major KOG/COG classifications, respectively, and were mainly annotated into 6,7,20 KEGG metabolic pathways. There were 654 metabolites detected in Zhengdan 309,40 differentially expressed metabolites(DEMs) were detected in Zhengdan 309 under high temperature stress for 7 d compared with that under the normal condition, of which 8 metablites were up-regulated,and 32 metablites were down-regulated.There were also 40 DEMs detected in Zhengdan 309 under high temperature stress for 14 d compared with that under the normal condition, including 4 up-regulated metablites and 36 down-regulated metablites.There were 46 DEMs detected in Zhengdan 309 under high temperature stress for 7 d compared with that under high temperature stress for 14 d, of which 17 metablites were up-regulated,and 29 metablites were down-regulated.The 40 DEMs in Zhengdan 309 under high temperature stress for 7 d compared with that under the normal condition were concentrated in biosynthesis of secondary metabolites, arginine and proline metabolism and other KEGG pathways.The 40 DEMs in Zhengdan 309 under high temperature stress for 14 d compared with that under the normal condition were concentrated in biosynthesis of secondary metabolites, steroid biosynthesis and other KEGG pathways.The 46 DEMs in Zhengdan 309 under high temperature stress for 7 d compared with that under high temperature stress for 14 d were mainly enriched in aminoacyl-tRNA biosynthesis, alanine,aspartate and glutamate metabolism and other KEGG pathways.

Key words: Maize, High temperature stress, Anthesis stage, High-throughput Illumina RNAsequencing, Metabonomics analysis, Differentially expressed genes(DEGs)

摘要： 利用Illumina HiSeqTM2500高通量转录组测序技术及广泛靶向代谢组测序技术对玉米新品种郑单309高温胁迫7、14 d及正常生长条件下材料的穗位叶进行高通量测序，从而分析高温胁迫相关差异表达基因、差异表达代谢物，以期发掘玉米响应高温胁迫的关键基因及代谢物。转录组测序结果显示，郑单309高温胁迫7 d与正常生长条件材料对比组中共检测到515个差异表达基因，其中75个为上调表达基因，440个为下调表达基因；高温胁迫14 d与正常生长条件材料对比组中共检测到506个差异表达基因，其中114个为上调表达基因，392个为下调表达基因；高温胁迫7 d与14 d对比组中检测到2 050个差异表达基因，其中790个为上调表达基因，1 260个为下调表达基因。郑单309高温胁迫7 d 与正常生长条件材料对比组中差异表达基因主要富集于细胞外区、分子功能调控等GO分类。郑单309高温胁迫14 d 与正常生长条件材料对比组中差异表达基因主要富集于节奏过程、细胞外区等GO分类。郑单309高温胁迫7 d 与14 d对比组中差异表达基因主要富集于单个有机体进程、细胞成分等GO分类。郑单309高温胁迫7 d 与正常生长条件材料对比组、高温胁迫14 d 与正常生长条件材料对比组、高温胁迫7 d 与14 d对比组中差异表达基因分别主要分布于5、7、15个KOG/COG分类，主要注释到6、7、20个KEGG代谢途经。代谢组学分析共检测到654个代谢物，郑单309高温胁迫7 d与正常生长条件材料对比组中检测到40个差异表达代谢物，其中8个上调表达，32个下调表达；郑单309高温胁迫14 d与正常生长条件材料对比组中检测到40个差异表达代谢物，其中4个上调表达，36个下调表达；郑单309高温胁迫7 d与14 d对比组中检测到46个差异表达代谢物，其中17个上调表达，29个下调表达。郑单309高温胁迫7 d与正常生长条件材料对比组中的40个差异表达代谢物主要富集于次生代谢产物生物合成、精氨酸及脯氨酸代谢等KEGG通路。郑单309高温胁迫14 d 与正常生长条件材料对比组中的40个差异表达代谢物主要富集于次生代谢产物生物合成、类黄酮生物合成等KEGG通路。郑单309高温胁迫7 d 与14 d对比组中的46个差异表达代谢物主要富集于氨酰tRNA生物合成，丙氨酸、天冬氨酸和谷氨酸代谢等KEGG通路。

关键词: 玉米, 高温胁迫, 花粒期, 高通量转录组测序, 代谢组学分析, 差异表达基因