玉米自交系响应高温、干旱胁迫的关键基因及通路

Key genes and pathways of maize inbred lines responding to heat and drought stress

以4个不同的玉米自交系为材料,对高温、干旱处理后的苗期植株进行转录组测序。玉米自交系响应高温和干旱胁迫的差异表达基因(DEGs)分别为6966和6272个,在高温和干旱胁迫下4个玉米自交系相同的DEGs分别是705和871个。同时响应高温和干旱的DEGs有100个。在耐旱、耐热性强的玉米自交系中鉴定出18个特异的DEGs,其中锌指转录因子、WRKY转录因子、GT转录因子和B2热激转录因子在胁迫响应中发挥关键的调控作用。KEGG通路分析结果表明,耐旱、耐热性强玉米自交响应高温干旱胁迫的DEGs富集在生物学过程、分子功能、代谢过程、遍在蛋白代谢和氮代谢途径5条通路。热带、亚热带玉米种质的耐旱、耐热性强于温带玉米种质,可在热带、亚热带玉米种质中有效筛选耐旱、耐热基因。

Transcriptome sequencing of the four different maize inbred lines subjected to high temperatures and water deficits,was performed at the stage of seedling.In total,6966 heat-responsive and 6272 drought-responsive differentially expressed genes(DEGs)were identified in the four maize lines.In addition,705 and 871 DEGs were identified as being commonly associated with heat and drought stress,respectively.There were 100 DEGs responding to both heat and drought stress.Eighteen DEGs were identified in maize inbred lines with strong drought tolerance and heat tolerance.The zinc finger transcription factor,WRKY transcription factor,GT transcription factor and B2 heat shock transcription factor played key regulatory roles in stress response.Analyses of KEGG pathway enrichment showed that the pathways such as biological process,molecular function,metabolic process,protein ubiquitination metabolism and nitrogen metabolism were the most highly enriched in the maize lines tolerant to heat and drought.It can be concluded that tropical and subtropical maize is tolerant to heat and drought,implying that it is plausible to screen goal genes in the tropical and subtropical germplasm.