School of Plant and Environmental Sciences

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https://hdl.handle.net/10919/91436
SPES was formed in 2017 from three departments: Crop and Soil Environmental Sciences; Horticulture; and Plant Pathology, Physiology, and Weed Science.

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Browsing School of Plant and Environmental Sciences by Subject "0604 Genetics"

Now showing 1 - 6 of 6
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    The Arabidopsis PHD-finger protein EDM2 has multiple roles in balancing NLR immune receptor gene expression
    Lai, Yan; Lu, Xueqing Maggie; Daron, Josquin; Pan, Songqin; Wang, Jianqiang; Wang, Wei; Tsuchiya, Tokuji; Holub, Eric; McDowell, John M.; Slotkin, R. Keith; Le Roch, Karine G.; Eulgem, Thomas (PLoS, 2020-09-01)
    Plant NLR-type receptors serve as sensitive triggers of host immunity. Their expression has to be well-balanced, due to their interference with various cellular processes and dose-dependency of their defense-inducing activity. A genetic “arms race” with fast-evolving pathogenic microbes requires plants to constantly innovate their NLR repertoires. We previously showed that insertion of the COPIA-R7 retrotransposon into RPP7 co-opted the epigenetic transposon silencing signal H3K9me2 to a new function promoting expression of this Arabidopsis thaliana NLR gene. Recruitment of the histone binding protein EDM2 to COPIA-R7-associated H3K9me2 is required for optimal expression of RPP7. By profiling of genome-wide effects of EDM2, we now uncovered additional examples illustrating effects of transposons on NLR gene expression, strongly suggesting that these mobile elements can play critical roles in the rapid evolution of plant NLR genes by providing the “raw material” for gene expression mechanisms. We further found EDM2 to have a global role in NLR expression control. Besides serving as a positive regulator of RPP7 and a small number of other NLR genes, EDM2 acts as a suppressor of a multitude of additional NLR genes. We speculate that the dual functionality of EDM2 in NLR expression control arose from the need to compensate for fitness penalties caused by high expression of some NLR genes by suppression of others. Moreover, we are providing new insights into functional relationships of EDM2 with its interaction partner, the RNA binding protein EDM3/AIPP1, and its target gene IBM1, encoding an H3K9-demethylase.
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    Arabidopsis UMAMIT24 and 25 are amino acid exporters involved in seed loading
    Besnard, Julien; Zhao, Chengsong; Avice, Jean-Christophe; Vitha, Stanislav; Hyodo, Ayumi; Pilot, Guillaume; Okumoto, Sakiko (Oxford University Press, 2018-10-12)
    Phloem-derived amino acids are the major source of nitrogen supplied to developing seeds. Amino acid transfer from the maternal to the filial tissue requires at least one cellular export step from the maternal tissue prior to the import into the symplasmically isolated embryo. Some members of UMAMIT (usually multiple acids move in an out transporter) family (UMAMIT11, 14, 18, 28, and 29) have previously been implicated in this process. Here we show that additional members of the UMAMIT family, UMAMIT24 and UMAMIT25, also function in amino acid transfer in developing seeds. Using a recently published yeast-based assay allowing detection of amino acid secretion, we showed that UMAMIT24 and UMAMIT25 promote export of a broad range of amino acids in yeast. In plants, UMAMIT24 and UMAMIT25 are expressed in distinct tissues within developing seeds; UMAMIT24 is mainly expressed in the chalazal seed coat and localized on the tonoplast, whereas the plasma membrane-localized UMAMIT25 is expressed in endosperm cells. Seed amino acid contents of umamit24 and umamit25 knockout lines were both decreased during embryogenesis compared with the wild type, but recovered in the mature seeds without any deleterious effect on yield. The results suggest that UMAMIT24 and 25 play different roles in amino acid translocation from the maternal to filial tissue; UMAMIT24 could have a role in temporary storage of amino acids in the chalaza, while UMAMIT25 would mediate amino acid export from the endosperm, the last step before amino acids are taken up by the developing embryo.
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    Detailed characterization of the UMAMIT proteins provides insight into their evolution, amino acid transport properties, and role in the plant
    Zhao, Chengsong; Pratelli, Rejane; Yu, Shi; Shelley, Brett; Collakova, Eva; Pilot, Guillaume (Oxford University Press, 2021-09-30)
    Amino acid transporters play a critical role in distributing amino acids within the cell compartments and between plant organs. Despite this importance, relatively few amino acid transporter genes have been characterized and their role elucidated with certainty. Two main families of proteins encode amino acid transporters in plants: the amino acid-polyamine-organocation superfamily, containing mostly importers, and the UMAMIT (usually multiple acids move in and out transporter) family, apparently encoding exporters, totaling 63 and 44 genes in Arabidopsis, respectively. Knowledge of UMAMITs is scarce, based on six Arabidopsis genes and a handful of genes from other species. To gain insight into the role of the members of this family and provide data to be used for future characterization, we studied the evolution of the UMAMITs in plants, and determined the functional properties, the structure, and localization of the 47 Arabidopsis UMAMITs. Our analysis showed that the AtUMAMITs are essentially localized at the tonoplast or the plasma membrane, and that most of them are able to export amino acids from the cytosol, confirming a role in intra- and intercellular amino acid transport. As an example, this set of data was used to hypothesize the role of a few AtUMAMITs in the plant and the cell.
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    The Evolution of an Invasive Plant, Sorghum halepense L. ('Johnsongrass')
    Paterson, Andrew H.; Kong, Wenqian; Johnston, Robyn M.; Nabukalu, Pheonah; Wu, Guohong; Poehlman, William L.; Goff, Valorie H.; Isaacs, Krista; Lee, Tae-Ho; Guo, Hui; Zhang, Dong; Sezen, U. Uzay; Kennedy, Megan; Bauer, Diane; Feltus, Frank A.; Weltzien, Eva; Rattunde, Henry Frederick; Barney, Jacob; Barry, Kerrie; Cox, T. Stan; Scanlon, Michael J. (Frontiers, 2020-05-14)
    From noble beginnings as a prospective forage, polyploid Sorghum halepense (‘Johnsongrass’) is both an invasive species and one of the world’s worst agricultural weeds. Formed by S. bicolor x S. propinquum hybridization, we show S. halepense to have S. bicolor-enriched allele composition and striking mutations in 5,957 genes that differentiate it from representatives of its progenitor species and an outgroup. The spread of S. halepense may have been facilitated by introgression from closely-related cultivated sorghum near genetic loci affecting rhizome development, seed size, and levels of lutein, a photochemical protectant and abscisic acid precursor. Rhizomes, subterranean stems that store carbohydrates and spawn clonal propagules, have growth correlated with reproductive rather than other vegetative tissues, and increase survival of both temperate cold seasons and tropical dry seasons. Rhizomes of S. halepense are more extensive than those of its rhizomatous progenitor S. propinquum, with gene expression including many alleles from its non-rhizomatous S. bicolor progenitor. The first surviving polyploid in its lineage in ∼96 million years, its post-Columbian spread across six continents carried rich genetic diversity that in the United States has facilitated transition from agricultural to non-agricultural niches. Projected to spread another 200–600 km northward in the coming century, despite its drawbacks S. halepense may offer novel alleles and traits of value to improvement of sorghum.
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    Mining germplasm panels and phenotypic datasets to identify loci for resistance to Phytophthora sojae in soybean
    Van, Kyujung; Rolling, William; Biyashev, Ruslan M.; Matthiesen, Rashelle L.; Abeysekara, Nilwala S.; Robertson, Alison E.; Veney, Deloris J.; Dorrance, Anne E.; McHale, Leah K.; Saghai-Maroof, Mohammad A. (Wiley, 2020-11-16)
    Phytophthora sojae causes Phytophthora root and stem rot of soybean and has been primarily managed through deployment of qualitative Resistance to P. sojae genes (Rps genes). The effectiveness of each individual or combination of Rps gene(s) depends on the diversity and pathotypes of the P. sojae populations present. Due to the complex nature of P. sojae populations, identification of more novel Rps genes is needed. In this study, phenotypic data from previous studies of 16 panels of plant introductions (PIs) were analyzed. Panels 1 and 2 consisted of 448 Glycine max and 520 G. soja, which had been evaluated for Rps gene response with a combination of P. sojae isolates. Panels 3 and 4 consisted of 429 and 460 G. max PIs, respectively, which had been evaluated using individual P. sojae isolates with complex virulence pathotypes. Finally, Panels 5–16 (376 G. max PIs) consisted of data deposited in the USDA Soybean Germplasm Collection from evaluations with 12 races of P. sojae. Using these panels, genome-wide association (GWA) analyses were carried out by combining phenotypic and SoySNP50K genotypic data. GWA models identified two, two, six, and seven novel Rps loci with Panels 1, 2, 3, and 4, respectively. A total of 58 novel Rps loci were identified using Panels 5–16. Genetic and phenotypic dissection of these loci may lead to the characterization of novel Rps genes that can be effectively deployed in new soybean cultivars against diverse P. sojae populations.
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    The transcriptional network of WRKY53 in cereals links oxidative responses to biotic and abiotic stress inputs
    Van Eck, Leon; Davidson, Rebecca M.; Wu, Shuchi; Zhao, Bingyu Y.; Botha, Anna-Maria; Leach, Jan E.; Lapitan, Nora L. V. (Springer, 2014-01-01)
    The transcription factor WRKY53 is expressed during biotic and abiotic stress responses in cereals, but little is currently known about its regulation, structure and downstream targets. We sequenced the wheat ortholog TaWRKY53 and its promoter region, which revealed extensive similarity in gene architecture and cis-acting regulatory elements to the rice ortholog OsWRKY53, including the presence of stress-responsive abscisic acid-responsive elements (ABRE) motifs and GCC-boxes. Four proteins interacted with the WRKY53 promoter in yeast one-hybrid assays, suggesting that this gene can receive inputs from diverse stress-related pathways such as calcium signalling and senescence, and environmental cues such as drought and ultraviolet radiation. The Ser/Thr receptor kinase ORK10/LRK10 and the apoplastic peroxidase POC1 are two downstream targets for regulation by the WRKY53 transcription factor, predicted based on the presence of W-box motifs in their promoters and coregulation with WRKY53, and verified by electrophoretic mobility shift assay (EMSA). Both ORK10/LRK10 and POC1 are upregulated during cereal responses to pathogens and aphids and important components of the oxidative burst during the hypersensitive response. Taken with our yeast two-hybrid assay which identified a strong protein-protein interaction between microsomal glutathione S-transferase 3 and WRKY53, this implies that the WRKY53 transcriptional network regulates oxidative responses to a wide array of stresses. © 2014 The Author(s).