Comparative transcriptome analysis of two contrasting wolfberry genotypes during fruit development and ripening and characterization of the LrMYB1 transcription factor that regulates flavonoid biosynthesis

Abstract

Background: Lycium barbarum and L. ruthenicum have been used as traditional medicinal plants in China and other Asian counties for centuries. However, the molecular mechanisms underlying fruit development and ripening, as well as the associated production of medicinal and nutritional components, have been little explored in these two species. Results: A competitive transcriptome analysis was performed to identify the regulators and pathways involved in the fruit ripening of red wolfberry (L. barbarum) and black wolfberry (L. ruthenicum) using an Illumina sequencing platform. In total, 155,606 genes and 194,385 genes were detected in red wolfberry (RF) and black wolfberry (BF), respectively. Of them, 20,335, 24,469, and 21,056 genes were differentially expressed at three different developmental stages in BF and RF. Functional categorization of the differentially expressed genes revealed that phenylpropanoid biosynthesis, flavonoid biosynthesis, anthocyanin biosynthesis, and sugar metabolism were the most differentially regulated processes during fruit development and ripening in the RF and BF. Furthermore, we also identified 38 MYB transcription factor-encoding genes that were differentially expressed during black wolfberry fruit development. Overexpression of LrMYB1 resulted in the activation of structural genes for flavonoid biosynthesis and led to an increase in flavonoid content, suggesting that the candidate genes identified in this RNA-seq analysis are credible and might offer important utility. Conclusion: This study provides novel insights into the molecular mechanism of Lycium fruit development and ripening and will be of value to novel gene discovery and functional genomic studies.

Floral transcriptomes reveal gene networks in pineapple floral growth and fruit development

“…In line with this results, Arabidopsis AIL5 ( AT5G57390 ), and ARF3 ( AT2G33860 ) and KAN2 ( AT1G32240 ) genes, the orthologs of the pineapple gene Aco014708 , and Aco021382 and Aco013194 belonging to the AP2/ERF:ERF, B3:ARF and GARP:G2-like TF family in supercluster 1 (Supplementary Data 8 ), which were also identified as eigengenes of the ovule (brown) module by WGCNA (Supplementary Data 3 ), were reported to play important roles in Arabidopsis ovule development 36 – 39 . MYB and GRAS TFs have been shown to involve in fruit development in black wolfberry and strawberry 40 , 41 . Notably, 19 MYB and 13 GRAS TFs were identified in the fruit-specific supercluster 2, suggesting the potential role of these MYB and GRAS TFs in regulating pineapple fruit development.…”

Shotgun proteomics of peach fruit reveals major metabolic pathways associated to ripening

“…Protein-coding genes whose products were more abundant in ripe compared to mature fruit also displayed an enrichment as NAC TFs targets, however they were mainly enriched as MYB TFs targets. MYB ripening-related TFs have been characterized in Lycium ruthenicum [ 109 ], in tomato [ 110 ], in papaya [ 101 ] and in plum ( P. salicina ) [ 111 ], indicating that MYBs might also be key in modulating the peach fruits pigmentation, flavour, and texture changes triggered by the fruit ripening [ 112 ].…”

Transcriptional regulation mechanism of flavonoids biosynthesis gene during fruit development in astragalus membranaceus

“…In our study, we used a combination of substance content and transcriptome to elucidate the molecular mechanism of flavonoids during fruit development. Meanwhile, many plants, such as L. japonica , Lycium barbarum and M. domestica , have studied the corresponding molecular mechanism through changes in substance content and gene expression during development ( Wang C. et al, 2020 ; Pu et al, 2020 ). These studies not only greatly deepened understanding the mechanism of substance synthesis and degradation, in the same time, it laid an important foundation to molecular regulation of fruit development improvement.…”