Author
Patrick P. Edger
Other affiliations: University of Arizona, University of California, Berkeley, University of California ...read more
Bio: Patrick P. Edger is an academic researcher from Michigan State University. The author has contributed to research in topics: Genome & Gene. The author has an hindex of 37, co-authored 106 publications receiving 6817 citations. Previous affiliations of Patrick P. Edger include University of Arizona & University of California, Berkeley.
Topics: Genome, Gene, Biology, Population, Polyploid
Papers
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University of Évry Val d'Essonne1, Crops Research Institute2, Agriculture and Agri-Food Canada3, J. Craig Venter Institute4, Fujian Agriculture and Forestry University5, Plant Genome Mapping Laboratory6, University of Giessen7, French Alternative Energies and Atomic Energy Commission8, Institut national de la recherche agronomique9, National Research Council10, Australian Centre for Plant Functional Genomics11, University of Cologne12, Purdue University13, University of California, Berkeley14, University of British Columbia15, Fondation Jean Dausset Centre d'Etude du Polymorphisme Humain16, Huazhong Agricultural University17, Hunan Agricultural University18, Chungnam National University19, University of Arizona20, University of York21, University of Missouri22, Southern Cross University23, University of Western Australia24, Centre national de la recherche scientifique25
TL;DR: The polyploid genome of Brassica napus, which originated from a recent combination of two distinct genomes approximately 7500 years ago and gave rise to the crops of rape oilseed, is sequenced.
Abstract: Oilseed rape (Brassica napus L.) was formed ~7500 years ago by hybridization between B. rapa and B. oleracea, followed by chromosome doubling, a process known as allopolyploidy. Together with more ancient polyploidizations, this conferred an aggregate 72× genome multiplication since the origin of angiosperms and high gene content. We examined the B. napus genome and the consequences of its recent duplication. The constituent An and Cn subgenomes are engaged in subtle structural, functional, and epigenetic cross-talk, with abundant homeologous exchanges. Incipient gene loss and expression divergence have begun. Selection in B. napus oilseed types has accelerated the loss of glucosinolate genes, while preserving expansion of oil biosynthesis genes. These processes provide insights into allopolyploid evolution and its relationship with crop domestication and improvement.
1,743 citations
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Fujian Agriculture and Forestry University1, University of Illinois at Urbana–Champaign2, Donald Danforth Plant Science Center3, University of Arizona4, Cold Spring Harbor Laboratory5, University of Georgia6, University of Hawaii7, University of Nevada, Reno8, University of Ottawa9, University of California10, Institut de recherche pour le développement11, University of Tennessee12, Texas A&M University13, Youngstown State University14, Kunming University of Science and Technology15, University of Adelaide16, National Taiwan University17, Oak Ridge National Laboratory18, United States Department of Agriculture19, Oklahoma State University–Stillwater20, University of Oxford21
TL;DR: The pineapple lineage has transitioned from C3 photosynthesis to CAM, with CAM-related genes exhibiting a diel expression pattern in photosynthetic tissues, providing the first cis-regulatory link between CAM and circadian clock regulation.
Abstract: Pineapple (Ananas comosus (L.) Merr.) is the most economically valuable crop possessing crassulacean acid metabolism (CAM), a photosynthetic carbon assimilation pathway with high water-use efficiency, and the second most important tropical fruit. We sequenced the genomes of pineapple varieties F153 and MD2 and a wild pineapple relative, Ananas bracteatus accession CB5. The pineapple genome has one fewer ancient whole-genome duplication event than sequenced grass genomes and a conserved karyotype with seven chromosomes from before the ρ duplication event. The pineapple lineage has transitioned from C3 photosynthesis to CAM, with CAM-related genes exhibiting a diel expression pattern in photosynthetic tissues. CAM pathway genes were enriched with cis-regulatory elements associated with the regulation of circadian clock genes, providing the first cis-regulatory link between CAM and circadian clock regulation. Pineapple CAM photosynthesis evolved by the reconfiguration of pathways in C3 plants, through the regulatory neofunctionalization of preexisting genes and not through the acquisition of neofunctionalized genes via whole-genome or tandem gene duplication.
424 citations
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University of Missouri1, University of Arizona2, University of California, Berkeley3, Max Planck Society4, University of Stirling5, University of Turku6, University of Cologne7, Leibniz Association8, McGill University9, California State University, Fullerton10, Pennsylvania State University11, Wageningen University and Research Centre12, University of Western Australia13, University of Alberta14, University of Toronto15, Stockholm University16
TL;DR: The coevolutionary interactions between plants and butterflies are examined, and evidence for an escalating evolutionary arms-race is uncovered, providing an important connection between the origins of biodiversity, coev evolution, and the role of gene and genome duplications as a substrate for novel traits.
Abstract: Coevolutionary interactions are thought to have spurred the evolution of key innovations and driven the diversification of much of life on Earth. However, the genetic and evolutionary basis of the innovations that facilitate such interactions remains poorly understood. We examined the coevolutionary interactions between plants (Brassicales) and butterflies (Pieridae), and uncovered evidence for an escalating evolutionary arms-race. Although gradual changes in trait complexity appear to have been facilitated by allelic turnover, key innovations are associated with gene and genome duplications. Furthermore, we show that the origins of both chemical defenses and of molecular counter adaptations were associated with shifts in diversification rates during the arms-race. These findings provide an important connection between the origins of biodiversity, coevolution, and the role of gene and genome duplications as a substrate for novel traits.
394 citations
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TL;DR: A near-complete chromosome-scale assembly for cultivated octoploid strawberry (Fragaria × ananassa) is reported and the origin and evolutionary processes that shaped this complex allopolyploid are uncovered, providing a useful resource for genome-wide analyses and molecular breeding.
Abstract: Cultivated strawberry emerged from the hybridization of two wild octoploid species, both descendants from the merger of four diploid progenitor species into a single nucleus more than 1 million years ago. Here we report a near-complete chromosome-scale assembly for cultivated octoploid strawberry (Fragaria × ananassa) and uncovered the origin and evolutionary processes that shaped this complex allopolyploid. We identified the extant relatives of each diploid progenitor species and provide support for the North American origin of octoploid strawberry. We examined the dynamics among the four subgenomes in octoploid strawberry and uncovered the presence of a single dominant subgenome with significantly greater gene content, gene expression abundance, and biased exchanges between homoeologous chromosomes, as compared with the other subgenomes. Pathway analysis showed that certain metabolomic and disease-resistance traits are largely controlled by the dominant subgenome. These findings and the reference genome should serve as a powerful platform for future evolutionary studies and enable molecular breeding in strawberry.
391 citations
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TL;DR: It is speculated that the preferential retention of dosage-sensitive genes and gene loss following WGDs has played a significant role in the development of morphological complexity in eukaryotes and facilitating speciation, respectively.
Abstract: Whole genome duplications (WGDs) followed by diploidization, which includes gene loss, have been an important recurrent process in the evolution of higher eukaryotes. Gene retention is biased to specific functional gene categories during diploidization. Dosage-sensitive genes, which include transcription factors, are significantly over-retained following WGDs. By contrast, these same functional gene categories exhibit lower retention rates following smaller scale duplications (e.g., local and tandem duplicates, segmental duplicates, aneuploidy). In light of these recent observations, we review current theories that address the fate of nuclear genes following duplication events (i.e., Gain of Function Hypothesis, Subfunctionalization Hypothesis, Increased Gene Dosage Hypothesis, Functional Buffering Model, and the Gene Balance Hypothesis). We broadly review different mechanisms of dosage-compensation that have evolved to alleviate harmful dosage-imbalances. In addition, we examine a recently proposed extension of the Gene Balance Hypothesis to explain the shared single copy status for a specific functional class of genes across the flowering plants. We speculate that the preferential retention of dosage-sensitive genes (e.g., regulatory genes such as transcription factors) and gene loss following WGDs has played a significant role in the development of morphological complexity in eukaryotes and facilitating speciation, respectively. Lastly, we will review recent findings that suggest polyploid lineages had increased rates of survival and speciation following mass extinction events, including the Cretaceous-Tertiary (KT) extinction.
355 citations
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01 Jun 2012
TL;DR: SPAdes as mentioned in this paper is a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler and on popular assemblers Velvet and SoapDeNovo (for multicell data).
Abstract: The lion's share of bacteria in various environments cannot be cloned in the laboratory and thus cannot be sequenced using existing technologies. A major goal of single-cell genomics is to complement gene-centric metagenomic data with whole-genome assemblies of uncultivated organisms. Assembly of single-cell data is challenging because of highly non-uniform read coverage as well as elevated levels of sequencing errors and chimeric reads. We describe SPAdes, a new assembler for both single-cell and standard (multicell) assembly, and demonstrate that it improves on the recently released E+V-SC assembler (specialized for single-cell data) and on popular assemblers Velvet and SoapDeNovo (for multicell data). SPAdes generates single-cell assemblies, providing information about genomes of uncultivatable bacteria that vastly exceeds what may be obtained via traditional metagenomics studies. SPAdes is available online ( http://bioinf.spbau.ru/spades ). It is distributed as open source software.
10,124 citations
01 Jan 2000
3,536 citations
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3,213 citations
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TL;DR: Comprehensive phylogenomic analyses of sequenced plant genomes and more than 12.6 million new expressed-sequence-tag sequences from phylogenetically pivotal lineages are used to elucidate two groups of ancient gene duplications, implicating two WGDs in ancestral lineages shortly before the diversification of extant seed plants and extant angiosperms.
Abstract: Whole-genome duplication (WGD), or polyploidy, followed by gene loss and diploidization has long been recognized as an important evolutionary force in animals, fungi and other organisms, especially plants. The success of angiosperms has been attributed, in part, to innovations associated with gene or whole-genome duplications, but evidence for proposed ancient genome duplications pre-dating the divergence of monocots and eudicots remains equivocal in analyses of conserved gene order. Here we use comprehensive phylogenomic analyses of sequenced plant genomes and more than 12.6 million new expressed-sequence-tag sequences from phylogenetically pivotal lineages to elucidate two groups of ancient gene duplications-one in the common ancestor of extant seed plants and the other in the common ancestor of extant angiosperms. Gene duplication events were intensely concentrated around 319 and 192 million years ago, implicating two WGDs in ancestral lineages shortly before the diversification of extant seed plants and extant angiosperms, respectively. Significantly, these ancestral WGDs resulted in the diversification of regulatory genes important to seed and flower development, suggesting that they were involved in major innovations that ultimately contributed to the rise and eventual dominance of seed plants and angiosperms.
1,763 citations
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TL;DR: Two channelrhodopsins, Chronos and Chrimson, are described, discovered through sequencing and physiological characterization of opsins from over 100 species of alga, that enable two-color activation of neural spiking and downstream synaptic transmission in independent neural populations without detectable cross-talk in mouse brain slice.
Abstract: Optogenetic tools enable examination of how specific cell types contribute to brain circuit functions. A long-standing question is whether it is possible to independently activate two distinct neural populations in mammalian brain tissue. Such a capability would enable the study of how different synapses or pathways interact to encode information in the brain. Here we describe two channelrhodopsins, Chronos and Chrimson, discovered through sequencing and physiological characterization of opsins from over 100 species of alga. Chrimson's excitation spectrum is red shifted by 45 nm relative to previous channelrhodopsins and can enable experiments in which red light is preferred. We show minimal visual system-mediated behavioral interference when using Chrimson in neurobehavioral studies in Drosophila melanogaster. Chronos has faster kinetics than previous channelrhodopsins yet is effectively more light sensitive. Together these two reagents enable two-color activation of neural spiking and downstream synaptic transmission in independent neural populations without detectable cross-talk in mouse brain slice.
1,701 citations