转录组和脂质代谢组联合分析不同紫苏α-亚麻酸合成调控差异OA

[Objective]This study aims to analyze the differences in α-linolenic acid(ALA)content between QO10 and QS5 seeds of Perilla frutescens,and find out genes related to ALA synthesis and regulation.The results will provide genetic resources for the further creation of new perilla varieties with high ALA content.[Method]Using morphological index determination,transcriptomics,and lipid metabolomics techniques,a systematic analysis was performed on the seed morphology,differentially expressed genes(DEGs),and lipid metabolite profiles of perilla QO10 and QS5.[Result]The 1 000-seed weight of QS5 seeds was significantly higher than that of QO10.Seed coat color difference analysis indicated that the seed coat color of QS5 was brighter than that of QO10,and the two were easily distinguishable in terms of seed coat color.Results of lipid metabolomics analysis demonstrated that there were significant differences in the types and relative contents of lipid metabolites between QO10 and QS5 seeds;the contents of stearic acid(SA)and ALA in QS5 seeds were higher than those in QO10.Transcriptomic analysis results showed that 188 differentially expressed genes(DEGs)were enriched in 6 GO terms and 5 KEGG pathways related to fatty acid(FA)metabolism.Based on the results of transcriptome-lipid metabolome integrated analysis,15 key enzyme and protein-coding genes were finally screened out.These included ACSL,FABP,FAD2,ENR,KAR,and KAS as well as lipase(lipase)-coding gene,LCAT3,FAR,SCL,and HMGCR.Furthermore,transcriptomic analysis revealed that 38 WRKY transcription factors(TFs)and 26 MYB TFs were differentially expressed;2 WRKY TFs and 2 MYB TFs with the largest fold changes in differential expression were selected as candidate TFs.Finally,10 candidate genes related to the regulation of ALA biosynthesis were verified by RT-qPCR,and the quantitative results were consistent with those of transcriptome sequencing.[Conclusion]There are significant morphological differences between the seeds of QO10 and QS5,and QS5 contained higher levels of SA and ALA.Nineteen genes related to the regulation of ALA biosynthesis are screened out,whose differential expression in QO10 and QS5 seeds is a potential cause of the difference in ALA content.