Transcriptome analyses reveal anthocyanin biosynthesis in eggplants

Abstract

We obtained a white-peel eggplant (L6-5) by EMS mutation in our previous study, whose total anthocyanin content was significantly decreased as compared with that of wild-type (WT). To analyse the anthocyanin biosynthesis mechanism in eggplants, we analysed the eggplant peel by RNA-seq in this study. The transcript results revealed upregulation of 465 genes and downregulation of 525 genes in L6-5 as compared with the WT eggplant. A total of 11 anthocyanin biosynthesis structure genes were significantly downregulated in L6-5 as compared with that in WT. Meanwhile, on the basis of the RT-PCR results of four natural eggplant cultivars, the expression pattern of 11 anthocyanin biosynthesis structure genes was consistent with the anthocyanin content. Thus, we speculated the anthocyanin biosynthesis pathway in eggplant peel. The transcript and RT-PCR results suggested positive regulation of MYB1, MYB108 and TTG8 and negative regulation of bHLH36 in anthocyanin biosynthesis. This study enhanced our cumulative knowledge about anthocyanin biosynthesis in eggplant peels.

Newly Developed MAGIC Population Allows Identification of Strong Associations and Candidate Genes for Anthocyanin Pigmentation in Eggplant

“…In eggplant, anthocyanin-related MYB protein-encoding genes have been reported to be related to fruit peel colouration ( Zhang et al, 2014 ; Docimo et al, 2016 ; Xiao et al, 2018 ; Moglia et al, 2020 ; Toppino et al, 2020 ). In tomato, a cluster of four different MYB proteins was reported to be involved in the anthocyanin synthesis located on chromosome 10 and encoded by SlAN2 , SlANT1 , SlANT1 -like, and SlAN2 -like genes (Solyc10g086250, Solyc10g086260, Solyc10g086270, and Solyc10g086290, respectively).…”

“…Quantitative trait locus (QTL)-related studies using family based or genome-wide association (GWA) mapping approaches evidenced that chromosome 10 harbours most of the QTL/genes involved in anthocyanin formation, distribution, and accumulation ( Doganlar et al, 2002 ; Barchi et al, 2012 ; Cericola et al, 2014 ; Frary et al, 2014 ; Toppino et al, 2016 , 2020 ; Wei et al, 2020 ). The availability of high-quality eggplant genome sequences and transcriptomic data allowed the identification of putative candidate genes belonging to the myeloblastosis (MYB) family which controls the variation in anthocyanin content and fruit colour in eggplant ( Docimo et al, 2016 ; Li et al, 2017 , 2018 , 2021 ; Xiao et al, 2018 ; Moglia et al, 2020 ; Shi et al, 2021 ), highlighting their synteny with other Solanaceae. However, the genes underlying the PUC phenotype have not been identified, so far.…”

Improved genome assembly and pan‐genome provide key insights into eggplant domestication and breeding

“…Anthocyanin biosynthesis is one of the most studied pathways in plants. Its control is strongly dependent on the tissue, developmental stage, and environment, and has been partially elucidated in eggplant (Barchi et al ., 2019b ; Moglia et al ., 2020 ; Xiao et al ., 2018 ; Zhang et al ., 2014 ). Modern eggplant varieties present anthocyanin pigmentation of the peel, whereas ancestral genotypes present non‐anthocyanic (white or green) fruits.…”

A New Intra-Specific and High-Resolution Genetic Map of Eggplant Based on a RIL Population, and Location of QTLs Related to Plant Anthocyanin Pigmentation and Seed Vigour

“…Each enzymatic step of this complex pathway is finely tuned by co-activators independent and functionally redundant R2R3-MYB regulatory proteins which regulate the expression of structural genes, alone or in complexes with other TFs belonging to the basic helix-loop-helix (BHLH) family. The control of the biosynthetic pathway is strongly dependent on tissue, developmental stage and environment, and has only been partially elucidated in eggplant with regard solely to the fruit peel coloration [ 36 , 103 , 105 , 106 , 107 , 108 ].…”