转录组解析外源ABA对玉米脱水速率的影响

Transcriptome Analysis Revealing the Mechanisms of Kernel Dehydration Rate Responding to ABA Application in Maize

为了探明迪卡517、郑单1002喷施外源ABA后脱水速率变化的分子机制,发掘影响脱水速率的关键差异表达基因及代谢通路,利用Illumina HiSeqTM2500测序仪分别对喷施ABA前后迪卡517(脱水速率较快)和郑单1002(脱水速率较慢)的穗位叶进行高通量转录组测序。原始序列经过质量控制、基因组比对、测序饱和度、基因覆盖度及冗余序列分析后进行基因功能注释。结果显示,迪卡517外源ABA处理与正常生长条件对比组检测到1732个差异表达基因,其中1251个为上调表达基因,481个为下调表达基因;郑单1002外源ABA处理与正常生长条件对比组检测到52个差异表达基因,其中24个为上调表达基因;迪卡517外源ABA处理与郑单1002外源ABA处理对比组检测到3867个差异表达基因,其中1946个为上调表达基因。不同对比组中筛选到差异表达基因GO分类情况、COG基因产物分类、KEGG代谢通路分析不同。转录因子分析共获得多个重要的转录因子家族,主要有AGC蛋白激酶家族、AP2/ERF转录因子家族、ARID转录因子、AUX/IAA转录因子家族、Alfin-like转录因子、Aur转录因子家族、B3转录因子家族、BBR-BPC转录因子家族、BES1转录因子、BUB转录因子、C2C2-CO-like转录因子等。Zm00001d035000、Zm00001d042063、Zm00001d045314等共同差异表达基因均在迪卡517和郑单1002中表达。对所有检测到的差异表达基因GO分类分析获得73个差异表达基因与水分代谢相关,推测这些基因作为外源ABA调控的下游基因起作用。

In order to explore the molecular mechanism of kernel dehydration rate changes and to find out the differentially expressed genes(DEGs)and metabolic pathways in DK517 and ZD1002 after spraying exogenous abiscisic acid(ABA)during grain-filling stage,the ear leaves of DK517(with faster dehydration rate)and ZD1002(with slower dehydration rate)before and after spraying ABA were used in sequencing with Illumina HiSeqTM2500 high-throughput sequencing technology.After sequence quality control,genome alignment,sequencing saturation,gene coverage and gene redundant analysis,gene functions were annotated with reference database.The results were as below:1732 DEGs were detected in DK517-ABA80 VS DK517-CK group,of which 1251 DEGs were up-regulated and 481 DEGs were down regulated.52 DEGs were detected in ZD1002-ABA80 VS ZD1002-CK group,24 of which were up regulated.There were 3867 DEGs,which were detected in DK517-ABA80 VS ZD1002-ABA80,of which 1946 DEGs were up regulated.The GO analysis,COG analysis and KEGG pathways were all different in the above three control groups.Important transcription factor families were obtained,including AGC protein kinase family,AP2/ERF transcription factor family,ARID transcription factor family,AUX/IAA transcription factor family,Alfin-like transcription factor family,Aur transcription factor family,B3 transcription factor family,BBR-BPC transcription factor family,BES1 transcription factor family,BUB transcription factor family and C2C2-CO-like transcription factor.Genes Zm00001d035000,Zm00001d042063,Zm00001d045314 were all expressing in DK517 and ZD1002.73 DEGs were related to water metabolism,which played important roles in kernel dehydration acting as downstream genes regulated by exogenous ABA.