Proteomic Analysis of Hylocereus polyrhizus Reveals Metabolic Pathway Changes

Abstract

Red dragon fruit or red pitaya (Hylocereus polyrhizus) is the only edible fruit that contains betalains. The color of betalains ranges from red and violet to yellow in plants. Betalains may also serve as an important component of health-promoting and disease-preventing functional food. Currently, the biosynthetic and regulatory pathways for betalain production remain to be fully deciphered. In this study, isobaric tags for relative and absolute quantitation (iTRAQ)-based proteomic analyses were used to reveal the molecular mechanism of betalain biosynthesis in H. polyrhizus fruits at white and red pulp stages, respectively. A total of 1946 proteins were identified as the differentially expressed between the two samples, and 936 of them were significantly highly expressed at the red pulp stage of H. polyrhizus. RNA-seq and iTRAQ analyses showed that some transcripts and proteins were positively correlated; they belonged to “phenylpropanoid biosynthesis”, “tyrosine metabolism”, “flavonoid biosynthesis”, “ascorbate and aldarate metabolism”, “betalains biosynthesis” and “anthocyanin biosynthesis”. In betalains biosynthesis pathway, several proteins/enzymes such as polyphenol oxidase, CYP76AD3 and 4,5-dihydroxy-phenylalanine (DOPA) dioxygenase extradiol-like protein were identified. The present study provides a new insight into the molecular mechanism of the betalain biosynthesis at the posttranscriptional level.

Integrated sRNAome and RNA-Seq analysis reveals miRNA effects on betalain biosynthesis in pitaya

“…Expression levels of Hmo-miR156, Hmo-miR157b, Hmo-miR164a, Hmo-miR164b and Hmo-miR399a increased gradually from 19 th DAF to 29 th DAF in ‘Guanhuahong’ pitaya. Those results were in consistent with betalain accumulation pattern [ 45 , 46 ]. However, the expression levels of Hmo-miR171c, Hmo-miR408, Hmo-miR393, Hmo-miR398c, Hmo-miR8175, Hmo-miR398a, Hmo-miR168a, Hmo-miR529b, Hmo-miR398b, Hmo-miR172a, Hmo-miR159a and Hmo-miR397b decreased gradually from 19 th DAF to 29 th DAF during fruit maturation of ‘Guanhuahong’ pitaya.…”

Integrated sRNAome and RNA-Seq Analysis Reveals miRNA Effects on Betalain Biosynthesis in Pitaya

“…Great progress has been made in pitaya betalain studies in term of physical and chemical properties [47,48], puri cation and identi cation [49][50][51][52][53][54], antioxidant and radical scavenging capacity [55][56][57] as well as metabolic and transcriptional analyses [45,46]. However, no information is available about miRNAs involved in betalain biosynthesis of pitaya.…”

Label-free quantitative proteomics to investigate the response of strawberry fruit after controlled ozone treatment

“…Phenylalanine ammonia-lyase, chalcone synthase (CHS), chalcone isomerase, avonoid 3-hydroxylase, dihydroavonol reductase, anthocyanidin synthase (ANS), and anthocyanidin 3-O-glucosyltransferase play important roles in the synthesis of anthocyanins and avonoids, and some proteins associated with transcription and the production of pigment also play a regulatory role. 57 The synthesis of anthocyanins, glycosides, and avonoids in strawberry fruit is shown in Fig. 12.…”