Browsing by Author "Fernandez-Pozo, Noe"

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    Natural variation in stress response gene activity in the allopolyploid Arabidopsis suecica
    Carlson, Keisha D.; Fernandez-Pozo, Noe; Bombarely, Aureliano; Pisupati, Rahul; Mueller, Lukas A.; Madlung, Andreas (2017-08-23)
    Background Allopolyploids contain genomes composed of more than two complete sets of chromosomes that originate from at least two species. Allopolyploidy has been suggested as an important evolutionary mechanism that can lead to instant speciation. Arabidopsis suecica is a relatively recent allopolyploid species, suggesting that its natural accessions might be genetically very similar to each other. Nonetheless, subtle phenotypic differences have been described between different geographic accessions of A. suecica grown in a common garden. Results To determine the degree of genomic similarity between different populations of A. suecica, we obtained transcriptomic sequence, quantified SNP variation within the gene space, and analyzed gene expression levels genome-wide from leaf material grown in controlled lab conditions. Despite their origin from the same progenitor species, the two accessions of A. suecica used in our study show genomic and transcriptomic variation. We report significant gene expression differences between the accessions, mostly in genes with stress-related functions. Among the differentially expressed genes, there are a surprising number of homoeologs coordinately regulated between sister accessions. Conclusions Many of these homoeologous genes and other differentially expressed genes affect transpiration and stomatal regulation, suggesting that they might be involved in the establishment of the phenotypic differences between the two accessions.
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    A reference genome for Nicotiana tabacum enables map-based cloning of homeologous loci implicated in nitrogen utilization efficiency
    Edwards, Kieron D.; Fernandez-Pozo, Noe; Drake-Stowe, Katherine; Humphry, Matthew Edward; Evans, Andy D.; Bombarely, Aureliano; Allen, Fraser; Hurst, R.; White, B.; Kernodle, Sheri P.; Bromley, Jennifer R.; Sanchez-Tamburrino, Juan Pablo; Lewis, Ramsey S.; Mueller, Lukas A. (2017-06-19)
    Background Tobacco (Nicotiana tabacum) is an important plant model system that has played a key role in the early development of molecular plant biology. The tobacco genome is large and its characterisation challenging because it is an allotetraploid, likely arising from hybridisation between diploid N. sylvestris and N. tomentosiformis ancestors. A draft assembly was recently published for N. tabacum, but because of the aforementioned genome complexities it was of limited utility due to a high level of fragmentation. Results Here we report an improved tobacco genome assembly, which, aided by the application of optical mapping, achieves an N50 size of 2.17 Mb and enables anchoring of 64% of the genome to pseudomolecules; a significant increase from the previous value of 19%. We use this assembly to identify two homeologous genes that explain the differentiation of the burley tobacco market class, with potential for greater understanding of Nitrogen Utilization Efficiency and Nitrogen Use Efficiency in plants; an important trait for future sustainability of agricultural production. Conclusions Development of an improved genome assembly for N. tabacum enables what we believe to be the first successful map-based gene discovery for the species, and demonstrates the value of an improved assembly for future research in this model and commercially-important species.
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    The Sol Genomics Network (SGN)-from genotype to phenotype to breeding
    Fernandez-Pozo, Noe; Menda, Naama; Edwards, Jeremy D.; Saha, Surya; Tecle, Isaak Y.; Strickler, Susan R.; Bombarely, Aureliano; Fisher-York, Thomas; Pujar, Anuradha; Foerster, Hartmut; Yan, Aimin; Mueller, Lukas A. (2015-01-28)
    The Sol Genomics Network (SGN, http://solgenomics.net) is a web portal with genomic and phenotypic data, and analysis tools for the Solanaceae family and close relatives. SGN hosts whole genome data for an increasing number of Solanaceae family members including tomato, potato, pepper, eggplant, tobacco and Nicotiana benthamiana. The database also stores loci and phenotype data, which researchers can upload and edit with user-friendly web interfaces. Tools such as BLAST, GBrowse and JBrowse for browsing genomes, expression and map data viewers, a locus community annotation system and a QTL analysis tools are available. A new tool was recently implemented to improve Virus-Induced Gene Silencing (VIGS) constructs called the SGN VIGS tool. With the growing genomic and phenotypic data in the database, SGN is now advancing to develop new web-based breeding tools and implement the code and database structure for other species or clade-specific databases.