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Platts, A.

Publications and source records attributed to Platts, A..

5 recordsLinked to original sources

Chromosome-scale genome assembly of the North American invasive Asteraceae, Tanacetum vulgare (common tansy)

Common tansy (Tanacetum vulgare), a significant agricultural invasive species, threatens forage productivity, livestock carrying capacity, and plant biodiversity across North American agroecosystems. Despite being a close relative to the ornamental Asteraceae Chrysanthemum, T. vulgare genomic studies are severely lacking, but remain critical to the development of novel weed management tools and the investigation of plant invasion evolution. In this study, we performed the assembly and annotation of the diploid genome (2n=2x=18) of an invasive North American T. vulgare genotype using long-read PacBio HiFi and Iso-Seq sequencing technology. The assembled haplotype genome comprised 9 pseudomolecules with a total size of ~4.8 Gb and a scaffold N50 of 546 Mb. In addition, both the plastid and mitochondrial genome sequences were assembled. BUSCO analysis revealed a high overall genome completeness with 69,343 predicted protein-coding genes (AED<0.6: 98%). A high-quality North American invasive reference T. vulgare genome, complementing a recent one assembled for a native European accession, is critical for the investigation of plant invasion biology, genome evolution, and the future development of novel genetic biocontrol weed management technologies.

genomics↗

SWIF-TE: identifying novel transposable element insertions from short read data

Transposable element (TE) insertion polymorphisms (TIPs) are TEs not in the same location between individuals. TIPs have contributed to genomic and phenomic variation but have been historically difficult to study due to their repetitive nature. Here, we describe a fast and memory-efficient tool to identify novel TIPs from short read sequences. SWIF-TE was able to identify 1,438 insertions at a precision rate of 27% using 0.10 Gb of memory and 0.82 hours of runtime from 15x resequencing data of a non-reference maize inbred. SWIF-TE is a powerful tool for studying TE variation in species with TE-rich genomes.

bioinformatics↗

Blueberry and cranberry pangenomes as a resource for future genetic studies and breeding efforts

Domestication of cranberry and blueberry began in the United States in the early 1800s and 1900s, respectively, and in part owing to their flavors and health-promoting benefits are now cultivated and consumed worldwide. The industry continues to face a wide variety of production challenges (e.g. disease pressures) as well as a demand for higher-yielding cultivars with improved fruit quality characteristics. Unfortunately, molecular tools to help guide breeding efforts for these species have been relatively limited compared with those for other high-value crops. Here, we describe the construction and analysis of the first pangenome for both blueberry and cranberry. Our analysis of these pangenomes revealed both crops exhibit great genetic diversity, including the presence-absence variation of 48.4% genes in highbush blueberry and 47.0% genes in cranberry. Auxiliary genes, those not shared by all cultivars, are significantly enriched with molecular functions associated with disease resistance and the biosynthesis of specialized metabolites, including compounds previously associated with improving fruit quality traits. The discovery of thousands of genes, not present in the previous reference genomes for blueberry and cranberry, will serve as the basis of future research and as potential targets for future breeding efforts. The pangenome, as a multiple-sequence alignment, as well as individual annotated genomes, are publicly available for analysis on the Genome Database for Vaccinium - a curated and integrated web-based relational database. Lastly, the core-gene predictions from the pangenomes will serve useful to develop a community genotyping platform to guide future molecular breeding efforts across the family.

genomics↗

Genetic architecture of spatially complex color patterning in hybrid Mimulus

Coloration in living organisms varies in hue, saturation, and pattern. Here we use genetic mapping to investigate all three elements in monkeyflowers Mimulus luteus var. variegatus and M. cupreus, whose flower petals differ in both yellow carotenoid and magenta anthocyanin pigmentation and whose hybrids exhibit anthocyanin pattern variation not seen in either parent. We report two QTLs associated with carotenoid intensity, and show that lighter yellow petals accumulate relatively high proportions of beta-carotene at the expense of downstream carotenoids. We propose that the derived loss of carotenoid saturation in M. l. variegatus is due to a function-reducing mutation in a Beta-Carotene Hydroxylase candidate gene, coupled with a reduction in the availability of carotenoid-storing chromoplasts influenced by the ORANGE candidate gene. We next identify five QTLs associated with the spatial patterning of anthocyanin pigment. Two QTLs, 9b and 23, each contain genes in the anthocyanin-activating subgroup of the MYB family. We hypothesize that MYB5a/NEGAN, at QTL-9b, activates spot formation in hybrids as part of a Turing-type reaction-diffusion system, while a MYB at QTL-23 activates solid, unpatterned anthocyanin pigment and may also be able to activate the variegatus allele of MYB5a/NEGAN. In addition to the apparently stochastic placement of most spots (consistent with a Turing mechanism), some pattern aspects - notably spots at the petal tips - appear to conform to a positional specification model in which spot location is predetermined. Collectively, this work begins to identify how combinations of yellow and red hues, shifts in carotenoid intensity, and two cryptic patterning systems all contribute to the complexity of color divergence between two close relatives.

genetics↗

Adaptive and maladaptive expression plasticity underlying herbicide resistance in an agricultural weed.

Plastic phenotypic responses to environmental change are common, yet we lack a clear understanding of the fitness consequences of these plastic responses. Here, we use the evolution of herbicide resistance in the common morning glory (Ipomoea purpurea) as a model for understanding the relative importance of adaptive and maladaptive gene expression responses to herbicide. Specifically, we compare leaf gene expression changes caused by herbicide to the expression changes that evolve in response to artificial selection for herbicide resistance. We identify a number of genes that show plastic and evolved responses to herbicide and find that for the majority of genes with both plastic and evolved responses, plastic responses appear to be adaptive. We also find that selection for herbicide response increases gene expression plasticity. Overall, these results show the importance of adaptive plasticity for herbicide resistance in a common weed and that expression changes in response to strong environmental change can be adaptive. Impact statementPredicting whether and how organisms will adapt to environmental change is a crucial goal. However, this goal can be complicated because environmental change can alter traits, in a process called plasticity. The extent and fitness consequences of plasticity will have important effects on the adaptive process. In this study, we use adaptation to herbicide in the agricultural weed, the common morning glory, as a model for understanding the extent and fitness consequences of plasticity in gene expression. We find evidence that gene expression plasticity is adaptive in the presence of herbicide, suggesting that understanding plasticity is crucial for understanding how organisms adapt to new environments.

evolutionary biology↗