Biology subjects

Arnold, G.

Publications and source records attributed to Arnold, G..

6 recordsLinked to original sources

bioRxiv2026

Genetic analysis of grapevine wood composition identifies glycosyltransferases involved in the biosynthesis of stilbene glycosides

Although wood extractives may play important roles in defense against pathogens, few studies have explored the genetic determinism of their accumulation. In this work, we have used a non-targeted metabolomic approach to perform a genetic analysis of grapevine (Vitis vinifera) wood extractive composition in a progeny from a cross between Riesling and Gewurztraminer. Metabolic quantitative trait loci (mQTL) analyses of cane and trunk wood extractives revealed a number of mQTLs. Analysis of one of these mQTL has led to the identification of a cluster of six UDP glycosyltransferase (UGT) genes linked to the accumulation of resveratrol-glucoside (piceid) in both canes and trunks. Detailed biochemical and structural characterization of these six UGTs highlighted a surprising functional diversity among this small gene family, as well as one UGT gene as a key determinant of the constitutive accumulation of piceid in lignified grapevine tissues. Molecular evolution analyses showed that the UGTs in this gene cluster were globally under strong purifying selection, suggesting important biological roles of the corresponding proteins. Moreover, the functional characterization showed that distinct UGT genes were involved in the biosynthesis of cis- and trans- isomers of piceid, suggesting that these isomers may play different biological roles in grapevine.

plant biology↗

bioRxiv2025

Comparative assessment of genomic, phenomic, and metabolomic prediction models in biparental grapevine breeding populations

Accelerating grapevine breeding for disease resistance and climate adaptation remains constrained by long generation cycles. We benchmarked genomic (SNP), phenomic (NIRS), and metabolomic (untargeted LC-MS) prediction for 24 agronomic traits in a biparental population phenotyped over three years. Seven statistical frameworks and four tissue x timepoint combinations (wood; vineyard leaves at budbreak and flowering; greenhouse leaves at flowering) were evaluated, together with feature-wise BLUPs across samples. Cross-year and cross-population analyses with two additional populations assessed temporal robustness and transferability. Genomic prediction was most accurate (up to r = 0.83), metabolomic prediction was intermediate (up to r = 0.59), and phenomic prediction was lowest (up to r = 0.39) despite its lower acquisition cost. Metabolite features were more heritable than NIR wavelengths, for which most unexplained variation remained residual under the fitted model. Multi-omics integration produced limited overall gains. These results support genomic selection as the primary approach, with metabolomic or phenomic screening considered only for traits and sampling designs that show reproducible predictive signal.

genomics↗

bioRxiv2025

Uncovering the genetic basis of agronomic traits in over 1,000 grapevine genotypes derived from a disease resistance breeding program

Breeding disease-resistant grapevines that retain agronomic performance under variable climates requires loci and predictions that transfer across related hybrid families. We analyzed 1,081 genotypes from 95 crosses within the French INRAE-ResDur breeding program for 13 phenology, yield and berry-composition traits evaluated at five sites from 2006 to 2024. We integrated within-family QTL mapping, kinship- and population-adjusted multiple-population QTL mapping in 772 progeny, and structure-aware GWAS in 899-968 individuals, depending on the trait, together with cross-environment, cross-trait and local genomic estimated breeding-value analyses. Genetic and phenotypic differentiation among families strongly affected locus detection. Of 76 family-QTL intervals, seven, representing six trait-region hypotheses, were locally concordant across all three mapping frameworks. The strongest recurrent evidence involved a chromosome-16 region for veraison and harvest date, where a localGEBV block at 14.69 Mb ranked first for veraison and second for harvest; chromosome-14 cluster traits and chromosome-1 compactness emerged as additional validation priorities. Cross-environment meta-analysis detected no common fixed-effect association at 5% FDR but revealed extensive heterogeneous evidence. Cross-trait analysis grouped 270 significant marker tests into 54 candidate multi-trait regions, without establishing biological pleiotropy. Population-adjusted localGEBV yielded a mean leave-one-population-out correlation of 0.470 between phenotypic BLUPs and genomic scores across traits. These results distinguish compact haplotype-validation targets from background- and environment-dependent signals, supporting a staged strategy that combines marker- assisted selection for validated recurrent regions with externally validated multi-trait, multi- environment genomic prediction for polygenic traits.

genetics↗

bioRxiv2023

Discovery of a locus associated with susceptibility to esca dieback in grapevine

Esca is the most destructive and predominant grapevine trunk diseases. The chronic infections and vine mortality caused by esca syndrome lead to huge economic losses and threatens the sustainability of vineyards worldwide. Although shown as associated with the presence of wood fungi, the etiology of esca remains still unclear and putatively involves multifactorial causes, which makes the development of effective control methods challenging. As differences in esca susceptibility had already been observed among grapevine varieties, we investigated in a biparental population the presence of genetic factors that can explain theses variations. Thanks to the destructive phenotyping of a 16-year-old vineyard plot, we discovered that the Gewurztraminer variety carries on chromosome 1 a locus linked to variations in trunk necrosis associated with esca, which we have named ENS1. Our study also suggests that there is a partial link between trunk vigor and necrosis due to esca. To our best knowledge, ENS1 is the first instance of genetic factor identified as involved in the limitation of necrosis associated to grapevine esca. While the identification of ENS1 alone may not provide a complete resolution of the esca issue, this discovery represents nonetheless a first step towards a genetic solution and paves the way for broader genetic investigations in the future.

genetics↗

bioRxiv2021

Visualizing sounds: training-induced plasticity with a visual-to-auditory conversion device

Sensory substitution devices aim at restoring visual functions by converting visual information into auditory or tactile stimuli. Although these devices show promises in the range of behavioral abilities they allow, the processes underlying their use remains underspecified. In particular, while an initial debate focused on the visual versus auditory or tactile nature of sensory substitution, since over a decade, the idea that it reflects a mixture of both has emerged. In order to investigate behaviorally the extent to which visual and auditory processes are involved, participants completed a Stroop-like crossmodal interference paradigm before and after being trained with a conversion device which translates visual images into sounds. In addition, participants auditory abilities and their phenomenologies were measured. Our study revealed that, after training, when asked to identify sounds, processes shared with vision were involved, as participants performance in sound identification was influenced by the simultaneously presented visual distractors. In addition, participants performance during training and their associated phenomenology depended on their auditory abilities, revealing that processing finds its roots in the input sensory modality. Our results pave the way for improving the design and learning of these devices by taking into account inter-individual differences in auditory and visual perceptual strategies. HighlightsO_LITrained people spontaneously use processes shared with vision when hearing sounds from the device C_LIO_LIProcesses with conversion devices find roots both in vision and audition C_LIO_LITraining with a visual-to-auditory conversion device induces perceptual plasticity C_LI

neuroscience↗

bioRxiv2020

Population history and the differential consequences of inbreeding and outcrossing in a plant metapoplation

The phenotypic consequences of inbreeding typically result in a fitness decline proportional to the increase in the inbreeding coefficient, F. This basic assumption of a predictable, inverse relationship between fitness and F has been questioned by a number of empirical studies. We explored the relationship between population history and inbreeding in a metapopulation of the plant Silene latifolia, for which long-term data are available for the historical size and spatial distribution of hundreds of local demes. We used a population genetic analysis to estimate gene flow and bi-parental inbreeding (FIS) in demes with different histories of spatial isolation. A controlled crossing experiment examined whether the effect of inbreeding and outcrossing on fitness-related traits varied with different histories of population size and isolation. Historically isolated demes experienced less gene flow and an increase in FIS, as well as significant inbreeding advantage and outbreeding depression for traits expressed early in life. The causes of variation in the F-fitness relationship among populations will include variance in the distribution of deleterious recessive alleles driven by aspects of population history, including population size, founder effects, gene flow, bi-parental inbreeding, and opportunities for the purging of genetic load. Our findings show that isolation and historical variation in population size likely contribute substantial variation in past inbreeding and the consequences of future inbreeding across the metapopulation.

evolutionary biology↗