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Caproni, L.

Publications and source records attributed to Caproni, L..

6 recordsLinked to original sources

AI-enabled simultaneous phenotyping of leaf vein and stomatal traits uncovers independent genetic control in maize

BackgroundLeaves maintain hydraulic homeostasis during photosynthesis through the coordinated action of stomata, which regulate gas exchange and transpiration, and veins, which supply water to the leaf lamina. While functional links between stomatal and vascular traits are known in dicots, their potential genetic coordination in C4 crops remains poorly understood. We investigated the genetic architecture of these traits in maize using a Multi-parent Advanced Generation Inter-Cross (MAGIC) population and a low-cost, high-throughput phenotyping platform integrating leaf clearing, digital microscopy, artificial intelligence, and image analysis ResultsWe phenotyped 285 recombinant inbred lines and the MAGIC founder lines, generating 8,072 images from 2,026 leaf samples taken from seedlings grown in controlled conditions. A YOLOv8-based model automatically detected stomata, while a custom and efficient image-processing pipeline quantified vein traits and stomatal spatial distribution patterns along cell bundles. This enabled simultaneous characterization of stomatal density, size, and distribution together with vein density, thickness, and bundle-associated spatial patterning. Substantial phenotypic variation was observed among genotypes, with strong correlations between abaxial and adaxial traits but no significant correlations between stomatal and vein traits. QTL mapping identified 37 genomic regions associated with stomatal and vein traits, including loci containing known developmental regulators such as stomatal density and distribution1 and stomagen1, as well as novel loci controlling stomatal spatial patterns, divergence between leaf surfaces and veins traits. ConclusionsThese results support independent genetic control of stomata and veins and decoupled contribution to water-use efficiency, providing a novel genetic framework to independently optimize leaf hydraulic capacity and gas exchange in target environments.

plant biology↗

SABER: A Multiparental Tomato Population Leveraging Wild Relative Diversity for High-Resolution QTL Mapping

The narrow genetic base of cultivated tomato (Solanum lycopersicum L.) represents a major constraint on crop improvement, necessitating the exploitation of wild relatives to broaden allelic diversity. Here we present SABER (Solanum lycopersicum Allele Biodiversity Enriched Resources), a novel eight-founder Multiparent Advanced Generation Intercross (MAGIC) population that, for the first time, incorporates the Galapagos wild relative Solanum cheesmaniae as a founder alongside seven elite S. lycopersicum lines. Following a structured crossing scheme and Single Seed Descent advancement, F6 recombinant inbred lines were genotyped at 5,850 high-confidence SNP markers using Single Primer Enrichment Technology (SPET). Population structure analyses confirmed low residual heterozygosity, limited substructure among offspring, and successful introgression of S. cheesmaniae alleles across all twelve chromosomes. Mapping performance was validated through three Mendelian traits with known genetic determinants, all of which resolved to genomic positions consistent with the literature. QTL mapping for quantitative agronomic traits identified known loci for fruit epicarp and flesh color, and two novel QTL for days to flowering, number of leaves before flowering, and soluble solids content. Together, these results demonstrate that SABER is a powerful and reliable platform for high-resolution QTL mapping and candidate gene discovery, and establish a replicable framework for integrating wild germplasm into multiparental tomato breeding resources

plant biology↗

Dual-antigen Doggybone DNA vaccine induces potent anti-tumor immunity against immunosuppressive oral cancer

Anti-PD1 blockade benefits only a subset of patients with head and neck squamous cell carcinoma (HNSCC), highlighting the need for approaches that overcome tumor immune resistance. Here, using the doggybone DNA (dbDNATM) platform, we developed CaVac OPT, an optimized dual-antigen DNA vaccine targeting MAGED4B and FJX1, which are overexpressed in most HPV-negative HNSCC and multiple solid tumors. In the MOC-2 oral cancer model, CaVac OPT significantly reduced tumor growth and when combined with anti-PD1 therapy, further delayed progression and improved survival. Immune profiling showed increased infiltration of CD4+ and CD8+ T cells, expansion of stem-like Tcf1+ populations, without increase in regulatory T cells, a reduced M2/M1 macrophage ratio and activation of interferon gamma associated pathways with suppression of tumor-promoting signals. These findings demonstrate that CaVac OPT reprograms the tumor microenvironment, converting cold HNSCC into T cell-inflamed responsive tumors. CaVac OPT represents a promising strategy for achieving durable control of aggressive, immunotherapy-resistant head and neck cancer.

cancer biology↗

The genetic basis of dynamic non-photochemical quenching and photosystem II efficiency in fluctuating light reveals novel molecular targets for maize (Zea mays) improvement

Maize (Zea mays L.) is a major global crop species which uses C4 photosynthesis. Although C4 is typically considered to be more efficient than C3 photosynthesis, especially under warmer and drier conditions, there is substantial evidence that its efficiency can still be further improved, which may benefit crop performance. Improving photosynthetic efficiency via targeted manipulation of non-photochemical quenching has focused on a limited set of genes that are known to be important determinants of the NPQ response in C3 plants. The C4 pathway may alter NPQ responses but only relatively few studies have explored genetic variation in NPQ kinetics in species that perform C4 photosynthesis. In addition, studies of NPQ responses in field-grown plants of either C3 or C4 species are especially limited. Here we apply high-definition phenotyping of NPQ responses and photosynthetic efficiency and quantitative trait locus (QTL) mapping using a field-grown maize Multi-parent Advanced Generation Inter-Cross (MAGIC) population, which combines the allelic diversity of eight contrasting inbred lines. We find substantial and consistent variation for dynamic NPQ and PSII efficiency for two subsequent field seasons. Further exploration of candidate genes within three major QTL regions identified a strong impact of allelic variation in expression of the minor PSII antenna protein CP24 (LHCB6) on a major QTL for NPQ and efficiency of PSII photochemistry on chromosome 10.

plant biology↗

Genomic and bioclimatic diversity of Ethiopian barley (Hordeum vulgare L.) landraces reveals vulnerability to climate change

The climate crisis is impacting agroecosystems of the global South, threatening the food security of millions of smallholder farmers. Understanding the effect of current and future climates on crop agrobiodiversity may guide breeding efforts and adaptation strategies to sustain the livelihoods of farmers cropping in challenging conditions. Here, we combine a genomic and climatic characterization of a large collection of traditional barley varieties from Ethiopia, key to food security in local smallholder farming systems. We employ data-driven approaches to characterize their local adaptation to current and future climates and identify barley genomic regions with potential for breeding for local adaptation. We used a sequencing approach to genotype at high- density 436 barley varieties, finding that their genetic diversity can be traced back to geography and environmental diversity in Ethiopia. We integrate this information in a genome-wide association study targeting phenology traits measured in common garden experiments as well as climatic features at sampling points of traditional varieties, describing 106 genomic loci associated with local adaptation. We then employ a machine learning approach to link barley genomic diversity with climate variation, estimating barley genomic offset in future climate scenarios. Our data show that the genomic characterization of traditional agrobiodiversity coupled with climate modelling may contribute to the mitigation of the climate crisis effects on smallholder farming systems.

genetics↗

Data-driven, participatory characterization of traditional farmer varieties discloses teff (Eragrostis tef) adaptive and breeding potential under current and future climates

In smallholder farming systems, traditional farmer varieties of neglected and underutilized species (NUS) support the livelihoods of millions of growers and consumers. NUS combine cultural and agronomic value with local adaptation and transdisciplinary methods are needed to fully evaluate their breeding potential. Here, we assembled and characterized the genetic diversity of a representative collection of 366 Ethiopian teff (Eragrostis tef) farmer varieties and breeding materials, describing their phylogenetic relation and local adaptation on the Ethiopian landscape. We phenotyped the collection for its agronomic performance, involving local farmers expert teff growers in a participatory variety evaluation. Our analyses revealed environmental patterns of teff genetic diversity and allowed us to identify ten genetic clusters associated with climate variation and with uneven spatial distribution. A genome wide association study (GWAS) was used to identify loci and candidate genes related to phenology, yield, local adaptation, and farmers appreciation. The estimated teff genomic offset under climate change scenarios highlighted an area around lake Tana where teff cropping may be most vulnerable to climate change. Our results show that transdisciplinary approaches may efficiently propel untapped NUS farmer varieties into modern breeding to foster more resilient and sustainable cropping systems.

genetics↗