不同抗逆性菠萝品种的差异基因和差异代谢物分析

Diversity Analysis of Differential Expressed Genes and Differential Metabolites between Two Pineapple Cultivars with Different Stress Resistance

该研究对2个不同抗逆性的菠萝品种PZ2(抗逆性较差)和PZ3(抗逆性强)进行转录组和代谢组比较分析,以探索品种间抗逆性差异的分子生理机制,为菠萝抗性育种提供理论依据。(1)转录组结果显示,以PZ2为对照,在2个品种间共筛选到1667个差异表达基因,上调和下调的差异表达基因分别为770个和897个;其中筛选到20个与抗逆性相关的差异表达基因,包括WRKY和MYB转录因子基因以及ASR3、SOD1、POD48、HSP20、GSTF1、GSTU17等基因。(2)代谢组分析表明,以PZ2为对照,在2个品种间共筛选到208个差异代谢物,含量上调和下调的差异代谢物分别为98个和110个,其中22种差异代谢物与抗逆性相关,包括氨基酸及其衍生物、脂类、黄酮类、糖类和糖苷等。(3)qRT-PCR分析验证表明,所选的8个差异表达基因在菠萝品种PZ2与PZ3中的差异表达趋势与转录组测序中差异基因表达水平变化趋势基本一致。(4)关联分析表明,差异表达基因和差异代谢物共同富集的通路有类黄酮生物合成,苯丙素生物合成,莨宕烷、哌啶和吡啶丙酸盐生物合成,半胱氨酸与蛋氨酸代谢等4条。研究发现,抗逆性强的菠萝品种的非生物逆境反应相关基因、抗氧化酶基因、逆境响应结构基因和调控基因的表达水平高于抗逆性较差的品种,且黄酮类、氨基酸衍生物类及木脂素、脂质等代谢物的含量也高于抗逆性较差的品种。

To investigate the molecular and physiological mechanisms associated with resistance diversity of different pineapple varieties,we utilized the two cultivars,PZ2 and PZ3 with differential stress-resistance in this work to comparatively analyze the transcriptome and metabolome.(1)The transcriptome sequencing results showed that a total of 1667 differential expressed genes were detected in PZ2 and PZ3 compar ison group.In PZ3,770 and 897 differential expressed genes were found to be up-and down-regulated when compared with PZ2,respectively,and 20 differential expressed genes were involved in adversity re-sistance,including ASR3,SOD1,POD48,HSP20,GSTF1,GSTU17,as well as WRKY and MYB transcription factor genes.(2)Metabolomics analysis indicated that a total of 208 differential metabolites were identified in PZ2 and PZ3 comparison group,98 and 110 of those were up-and down-regulated in con-tents in PZ3 when compared with PZ2,respectively.Totally,22 differential metabolites were found to be associated with adversity resistance,including amino acids and derivatives,lipids,flavanols,carbohy-drates and glycosides.(3)It showed that the expression profiles of the eight genes revealed by qPCR were consistent with the corresponding RPKM values derived from RNA-seq.(4)The correlation analysis showed that the pathways for co-enrichment of differentially expressed genes and differential metabolites included flavonoid biosynthesis,phenylpropanoid biosynthesis,tropane,piperidine and pyridine alkaloid biosynthesis,and cysteine and methionine metabolism.It was found that the expression levels of abiotic stress responsive genes,antioxidant enzyme genes,as well as structure and regulatory genes response to stress,were higher in the pineapple cultivar with strong stress resistance than those of the cultivar with stress-poor resistance.Also,the contents of flavonoids,amino acids and derivatives,as well as lignans and lipids metabolites were higher than those of cultivar with stress-poor resistance.The data of this work would contribute to provide references for the comparative analysis of mechanism of pineapple varieties re-lated to different resistance and to provide a theoretical basis for pineapple resistance breeding.