Target enrichment sequencing coupled with GWAS identifies MdPRX10 as a candidate gene in the control of budbreak in apple

The timing of floral budbreak in apple has a significant effect on fruit production and quality. Budbreak occurs as a result of a complex molecular mechanism that relies on accurate integration of external environmental cues, principally temperature. In the pursuit of understanding this mechanism, especially with respect to aiding adaptation to climate change, a QTL at the top of linkage group (LG) 9 has been identified by many studies on budbreak, but the genes underlying it remain elusive. Here, together with a dessert apple core collection of 239 cultivars, we used a targeted capture sequencing approach to increase SNP resolution in apple orthologues of known or suspected A. thaliana flowering time-related genes, as well as approximately 200 genes within the LG9 QTL interval. This increased the 275 223 SNP Axiom® Apple 480 K array dataset by an additional 40 857 markers. Robust GWAS analyses identified MdPRX10, a peroxidase superfamily gene, as a strong candidate that demonstrated a dormancy-related expression pattern and down-regulation in response to chilling. In-silico analyses also predicted the residue change resulting from the SNP allele associated with late budbreak could alter protein conformation and likely function. Late budbreak cultivars homozygous for this SNP allele also showed significantly up-regulated expression of C-REPEAT BINDING FACTOR (CBF) genes, which are involved in cold tolerance and perception, compared to reference cultivars, such as Gala. Taken together, these results indicate a role for MdPRX10 in budbreak, potentially via redox-mediated signaling and CBF gene regulation. Moving forward, this provides a focus for developing our understanding of the effects of temperature on flowering time and how redox processes may influence integration of external cues in dormancy pathways

Synthesis of oligosaccharides of the linkage region of proteoglycans using regioselective glycosylation

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Development of oligosaccharide effectors targeting the chondroitin-sulfate N-acetylgalactosaminyltransferase-I (CSGalNAcT-I), a key step to control chondroitin-sulfate initiation?

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Genome-wide association study based on highthroughput phenotyping reveals genomic regions invovlved in the control of architectural and physiological traits in Apple tree

International audienceGenotypic variations in fruit tree architectural and functional traits have been reported but their genetic bases and the existence of common geneticdeterminants have rarely been investigated in wide genetic diversity. We made use of innovative in-eld high-throughput phenotyping on anassociation panel of 241 genotypes to quantify architectural and functional traits on 4-years old apple trees. T-Lidar technology was used for estimatingarchitectural traits (number of branches, tree height, STAR…), airborne thermal and multispectral imagery for assessing canopy temperature (a proxyof transpiration rate) and vegetation indices (NDVI, MCARI2, GNDVI). This dataset was complemented with yield-related traits (number of fruits, averagefruit weight). We explored genome wide associations on 16 traits with high density (275K) genotypic data. GWAS was run with a multi-locus mixedmodel using genetic kinship matrix and assuming different thresholds for SNP signicance: (i) the Bonferroni correction (Bonfth, -logpval > 6.7), (ii) acorrection based on an estimated number of independent SNPs (Bonfcor, -logpval > 5.7) and (iii) value based on common practices (-logpval = 5).Signicant SNPs with -logpval > 5 were detected for most traits with a number of them displaying -logpval above Bonfcor and above Bonfth. One to foursignicant SNPs were identied by variable with a proportion of variance explained by each SNP ranging from 6% to 14% and the total proportion ofvariance explained by all signicant SNPs exceeding up to 30% for the number of branches, STAR, MCARI2, number of fruit and crop load. SNPscontrolling different traits were detected on LG9 (height, STAR, volume) and LG13 (volume, MCARI2, NDVI, GNDVI). Analyses of the LD between SNPsallowed determining possible colocations within regions. Notably, some signicant SNPs were localized in genomic regions previously reported as QTLsfor similar traits in bi-parental population. This suggests their robustness and encourages further investigations

Piezoelectric Properties at the Macro- and Nanoscale Levels and Microstructure in Ba_0.85Ca_0.15Ti_0.9Zr_0.1O₃ (BCTZ) Thin Films Grown by Pulsed Laser Deposition

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Microstructure, Macro- and Nanoscale Piezoelectric Properties in Ba_0.85Ca_0.15Ti_0.9Zr_0.1O₃ (BCTZ) Thin Films Grown by Pulsed Laser Deposition on Various Substrates for Energy Harvesting

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Staphylococcus capitis isolated from bloodstream infections: a nationwide 3-month survey in 38 neonatal intensive care units

International audienceTo increase the knowledge about S. capitis in the neonatal setting, we conducted a nationwide 3-month survey in 38 neonatal intensive care units (NICUs) covering 56.6% of French NICU beds. We demonstrated 14.2% of S. capitis BSI (S.capBSI) among nosocomial BSIs. S.capBSI incidence rate was 0.59 per 1000 patient-days. A total of 55.0% of the S.capBSIs were late onset catheter-related BSIs. The S. capitis strains infected preterm babies (median gestational age 26 weeks, median birth weight 855 g). They were resistant to methicillin and aminoglycosides and belonged to the NRCS-A clone. Evolution was favorable in all but one case, following vancomycin treatment

High-risk exposure without personal protective equipment and infection with SARS-CoV-2 in-hospital workers - The CoV-CONTACT cohort.

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Relationship between serotypes, disease characteristics and 30-day mortality in adults with invasive pneumococcal disease

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