Integrative Multi-omics Profiling of Passion Fruit Reveals the Genetic Basis for Fruit Color and Aroma
Published:15 Dec.2023 Source:Plant Physiology
Passion fruit (Passiflora edulis) possesses a complex aroma and is widely grown in tropical and subtropical areas. Here, we conducted the de novo assembly, annotation and comparison of purple (P. edulis Sims) and yellow passion fruit (P. edulis f. flavicarpa) reference genomes using PacBio, Illumina and Hi-C technologies. Notably, we discovered evidence of recent whole-genome duplication events in P. edulis genomes.
Comparative analysis revealed 7.6~8.1 million single nucleotide polymorphisms, one million insertions/deletions, and over 142 Mb presence/absence variations among different P. edulis genomes. During the ripening of yellow passion fruit, metabolites related to flavor, aroma, and color were substantially accumulated or changed. Through joint analysis of genomic variations, differentially expressed genes, and accumulated metabolites, we explored candidate genes associated with flavor, aroma and color distinctions. Flavonoid biosynthesis pathways, anthocyanin biosynthesis pathways and related metabolites are pivotal factors affecting the coloration of passion fruit, and terpenoids metabolites accumulated more in purple passion fruit. Finally, by heterologous expression in yeast (Saccharomyces cerevisiae), we functionally characterized 12 terpene synthases (TPSs).
Our findings revealed that certain TPS homologues in both yellow and purple passion fruit varieties produce identical terpene products, while others yield distinct compounds or even lose their functionality. These discoveries revealed the genetic and metabolic basis of unique characteristics in aroma and flavor between the two passion fruit varieties. This study provides resources for better understanding the genome architecture and accelerating genetic improvement of passion fruits.