Genetic analysis of a white-to-red berry skin color reversion and its transcriptomic and metabolic consequences in grapevine (Vitis vinifera cv. ‘Moscatel Galego’)

Abstract

BackgroundSomatic mutations occurring within meristems of vegetative propagation material have had a major role in increasing the genetic diversity of the domesticated grapevine (Vitis vinifera subsp. vinifera). The most well studied somatic variation in this species is the one affecting fruit pigmentation, leading to a plethora of different berry skin colors. Color depletion and reversion are often observed in the field. In this study we analyzed the origin of a novel white-to-red skin color reversion and studied its possible metabolic and transcriptomic consequences on cv. ‘Muscat à Petits Grains Blancs’ (synonym cv. ‘Moscatel Galego Branco’), a member of the large family of Muscats.ResultsThe mild red-skinned variant (cv. ‘Muscat à Petits Grains Rouge’, synonym cv. ‘Moscatel Galego Roxo’), characterized by a preferential accumulation of di-hydroxylated anthocyanins, showed in heterozygosis a partially-excised Gret1 retrotransposon in the promoter region of the MYBA1 anthocyanin regulator, while MYBA2 was still in homozygosis for its non-functional allele. Through metabolic (anthocyanin, resveratrol and piceid quantifications) and transcriptomic (RNA-Seq) analyses, we show that within a near-isogenic background, the transcriptomic consequences of color reversion are largely associated to diminished light/UV-B responses probably as a consequence of the augment of metabolic sunscreens (i.e. anthocyanins).ConclusionsWe propose that the reduced activity of the flavonoid tri-hydroxylated sub-branch and decreased anthocyanin synthesis and modification (e.g. methylation and acylation) are the potential causes for the mild red-skinned coloration in the pigmented revertant. The observed positive relation between anthocyanins and stilbenes could be attributable to an increased influx of phenylpropanoid intermediaries due to the replenished activity of MYBA1, an effect yet to be demonstrated in other somatic variants.

Berry Anthocyanin, Acid, and Volatile Trait Analyses in a Grapevine-Interspecific F2 Population Using an Integrated GBS and rhAmpSeq Genetic Map

“…Berry color is produced by synthesis and accumulation of anthocyanins in the berry skin and MYB and bHLH family genes have been identified as contributing to skin color development [ 17 , 44 , 45 ]. The VvMYBA1 gene on chromosome 2 has been identified as one of the main genes for berry color [ 9 ].…”

Identification of ABA-Mediated Genetic and Metabolic Responses to Soil Flooding in Tomato (Solanum lycopersicum L. Mill)

“…The libraries for RNASeq were prepared from 3 μg of total RNA using the TruSeq Stranded mRNA LT Sample Prep Kit (Illumina Inc., San Diego, CA, United States) and pair-end sequenced using the NovaSeq 6000 platform, producing 151 nt-long reads. Bioinformatics analysis was carried out using the Artificial Intelligence RNASeq (AIR) platform 1 as in Ferreira et al (2019) . The quality of the raw reads was checked with FastQC and sequence trimming to remove low-quality bases, and sequencing adaptors were performed with the tool BBDuk.…”

Secondary Metabolism and Defense Responses Are Differently Regulated in Two Grapevine Cultivars during Ripening

“…VvSTS16 and VvSTS48 were classified in two different groups that are differentially expressed in response to diverse environmental stimuli. The accumulation of stilbenoids at harvest was previously reported [ 53 ], as well as possible crosstalk between the upregulation of STSs and the accumulation of anthocyanins in berries [ 13 , 54 ]. Interestingly, in the absence of biotic and abiotic stresses, grapes accumulate stilbenoids during ripening, with a variable efficiency based on the genotype.…”