Transcriptomics-Metabolomics Combined Analysis Highlight the Anthocyanin Biosynthesis Mechanism of Red Testa in Peanut(Arachis hypogaea L.)
Peanut is the important unique export agricultural product,which occupies a vital position in agricultural development of China.In this study,two peanut varieties,Hongzhenzhu(H)and Baizhenzhu(B,the control),were used as research samples for transcriptomic-metabolomics combined analysis.At 30 and 45 days after flowering,the testa color(L value,a value,b value)and anthocyanin content of Hongzhenzhu and Baizhenzhu were extremely significantly different between varieties.FPKM hierarchical cluster analysis showed that compared with Baizhenzhu,there were 1847 and 1843 unique genes at 30 and 45 days after flowering in Hongzhenzhu,respectively.GO analysis annotation results showed there were 8 GO terms significantly related to anthocyanin synthesis.Among them,GO:0055114 and GO:0016207 had enriched with 8(C4H、two CHS、F3'H、two FLS、F3H and PAL)and 7(two CHS、CHI、F3'H、two FLS and F3H)differential expressed geness respectively.The results of KEGG enrichment analysis showed that 6 metabolic pathways were significantly related to anthocyanin biosynthesis,respectively.Metabolomics results showed that cyanidin,procyanidin,petunidin,delphinidin,malvidin,peony(peonidin)and their derivatives were differential accumulated metabolites(DAMs).The transcriptomics-metabolomics combined analysis showed that flavonoid biosynthesis(ko00941)is the key synthetic pathway and delphin and centaurea are the key DAMs of testa color formation.The qRT-PCR result of 11 detected DEGs was consistent with the results of transcriptome sequencing.These results of this study have a certain reference significance for revealing the regulatory mechanism of anthocyanin synthesis in peanut testa.