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Li-Jun Ma

Bio: Li-Jun Ma is an academic researcher from University of Massachusetts Amherst. The author has contributed to research in topics: Genome & Fusarium oxysporum. The author has an hindex of 29, co-authored 80 publications receiving 13217 citations. Previous affiliations of Li-Jun Ma include Massachusetts Institute of Technology & State University of New York College of Environmental Science and Forestry.


Papers
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Journal ArticleDOI
24 Apr 2003-Nature
TL;DR: A high-quality draft sequence of the N. crassa genome is reported, suggesting that RIP has had a profound impact on genome evolution, greatly slowing the creation of new genes through genomic duplication and resulting in a genome with an unusually low proportion of closely related genes.
Abstract: Neurospora crassa is a central organism in the history of twentieth-century genetics, biochemistry and molecular biology. Here, we report a high-quality draft sequence of the N. crassa genome. The approximately 40-megabase genome encodes about 10,000 protein-coding genes—more than twice as many as in the fission yeast Schizosaccharomyces pombe and only about 25% fewer than in the fruitfly Drosophila melanogaster. Analysis of the gene set yields insights into unexpected aspects of Neurospora biology including the identification of genes potentially associated with red light photobiology, genes implicated in secondary metabolism, and important differences in Ca21 signalling as compared with plants and animals. Neurospora possesses the widest array of genome defence mechanisms known for any eukaryotic organism, including a process unique to fungi called repeat-induced point mutation (RIP). Genome analysis suggests that RIP has had a profound impact on genome evolution, greatly slowing the creation of new genes through genomic duplication and resulting in a genome with an unusually low proportion of closely related genes.

1,659 citations

Journal ArticleDOI
21 Apr 2005-Nature
TL;DR: The draft sequence of the M. grisea genome is reported, reflecting the clonal nature of this fungus imposed by widespread rice cultivation and analysis of the gene set provides an insight into the adaptations required by a fungus to cause disease.
Abstract: Magnaporthe grisea is the most destructive pathogen of rice worldwide and the principal model organism for elucidating the molecular basis of fungal disease of plants. Here, we report the draft sequence of the M. grisea genome. Analysis of the gene set provides an insight into the adaptations required by a fungus to cause disease. The genome encodes a large and diverse set of secreted proteins, including those defined by unusual carbohydrate-binding domains. This fungus also possesses an expanded family of G-protein-coupled receptors, several new virulence-associated genes and large suites of enzymes involved in secondary metabolism. Consistent with a role in fungal pathogenesis, the expression of several of these genes is upregulated during the early stages of infection-related development. The M. grisea genome has been subject to invasion and proliferation of active transposable elements, reflecting the clonal nature of this fungus imposed by widespread rice cultivation.

1,520 citations

Journal ArticleDOI
18 Mar 2010-Nature
TL;DR: Comparison of genomes of three phenotypically diverse Fusarium species revealed lineage-specific genomic regions in F. oxysporum that include four entire chromosomes and account for more than one-quarter of the genome, putting the evolution of fungal pathogenicity into a new perspective.
Abstract: Fusarium species are among the most important phytopathogenic and toxigenic fungi. To understand the molecular underpinnings of pathogenicity in the genus Fusarium, we compared the genomes of three phenotypically diverse species: Fusarium graminearum, Fusarium verticillioides and Fusarium oxysporum f. sp. lycopersici. Our analysis revealed lineage-specific (LS) genomic regions in F. oxysporum that include four entire chromosomes and account for more than one-quarter of the genome. LS regions are rich in transposons and genes with distinct evolutionary profiles but related to pathogenicity, indicative of horizontal acquisition. Experimentally, we demonstrate the transfer of two LS chromosomes between strains of F. oxysporum, converting a non-pathogenic strain into a pathogen. Transfer of LS chromosomes between otherwise genetically isolated strains explains the polyphyletic origin of host specificity and the emergence of new pathogenic lineages in F. oxysporum. These findings put the evolution of fungal pathogenicity into a new perspective.

1,386 citations

Journal ArticleDOI
Brian J. Haas1, Sophien Kamoun2, Sophien Kamoun3, Michael C. Zody4, Michael C. Zody1, Rays H. Y. Jiang5, Rays H. Y. Jiang1, Robert E. Handsaker1, Liliana M. Cano3, Manfred Grabherr1, Chinnappa D. Kodira6, Chinnappa D. Kodira1, Sylvain Raffaele3, Trudy Torto-Alalibo2, Trudy Torto-Alalibo6, Tolga O. Bozkurt3, Audrey M. V. Ah-Fong7, Lucia Alvarado1, Vicky L. Anderson8, Miles R. Armstrong9, Anna O. Avrova9, Laura Baxter10, Jim Beynon10, Petra C. Boevink9, Stephanie R. Bollmann11, Jorunn I. B. Bos2, Vincent Bulone12, Guohong Cai13, Cahid Cakir2, James C. Carrington14, Megan Chawner15, Lucio Conti16, Stefano Costanzo11, Richard Ewan16, Noah Fahlgren14, Michael A. Fischbach17, Johanna Fugelstad12, Eleanor M. Gilroy9, Sante Gnerre1, Pamela J. Green18, Laura J. Grenville-Briggs8, John Griffith15, Niklaus J. Grünwald11, Karolyn Horn15, Neil R. Horner8, Chia-Hui Hu19, Edgar Huitema2, Dong-Hoon Jeong18, Alexandra M. E. Jones3, Jonathan D. G. Jones3, Richard W. Jones11, Elinor K. Karlsson1, Sridhara G. Kunjeti20, Kurt Lamour21, Zhenyu Liu2, Li-Jun Ma1, Dan MacLean3, Marcus C. Chibucos22, Hayes McDonald23, Jessica McWalters15, Harold J. G. Meijer5, William Morgan24, Paul Morris25, Carol A. Munro8, Keith O'Neill1, Keith O'Neill6, Manuel D. Ospina-Giraldo15, Andrés Pinzón, Leighton Pritchard9, Bernard H Ramsahoye26, Qinghu Ren27, Silvia Restrepo, Sourav Roy7, Ari Sadanandom16, Alon Savidor28, Sebastian Schornack3, David C. Schwartz29, Ulrike Schumann8, Ben Schwessinger3, Lauren Seyer15, Ted Sharpe1, Cristina Silvar3, Jing Song2, David J. Studholme3, Sean M. Sykes1, Marco Thines30, Marco Thines3, Peter J. I. van de Vondervoort5, Vipaporn Phuntumart25, Stephan Wawra8, R. Weide5, Joe Win3, Carolyn A. Young2, Shiguo Zhou29, William E. Fry13, Blake C. Meyers18, Pieter van West8, Jean B. Ristaino19, Francine Govers5, Paul R. J. Birch31, Stephen C. Whisson9, Howard S. Judelson7, Chad Nusbaum1 
17 Sep 2009-Nature
TL;DR: The sequence of the P. infestans genome is reported, which at ∼240 megabases (Mb) is by far the largest and most complex genome sequenced so far in the chromalveolates and probably plays a crucial part in the rapid adaptability of the pathogen to host plants and underpins its evolutionary potential.
Abstract: Phytophthora infestans is the most destructive pathogen of potato and a model organism for the oomycetes, a distinct lineage of fungus-like eukaryotes that are related to organisms such as brown algae and diatoms. As the agent of the Irish potato famine in the mid-nineteenth century, P. infestans has had a tremendous effect on human history, resulting in famine and population displacement(1). To this day, it affects world agriculture by causing the most destructive disease of potato, the fourth largest food crop and a critical alternative to the major cereal crops for feeding the world's population(1). Current annual worldwide potato crop losses due to late blight are conservatively estimated at $6.7 billion(2). Management of this devastating pathogen is challenged by its remarkable speed of adaptation to control strategies such as genetically resistant cultivars(3,4). Here we report the sequence of the P. infestans genome, which at similar to 240 megabases (Mb) is by far the largest and most complex genome sequenced so far in the chromalveolates. Its expansion results from a proliferation of repetitive DNA accounting for similar to 74% of the genome. Comparison with two other Phytophthora genomes showed rapid turnover and extensive expansion of specific families of secreted disease effector proteins, including many genes that are induced during infection or are predicted to have activities that alter host physiology. These fast-evolving effector genes are localized to highly dynamic and expanded regions of the P. infestans genome. This probably plays a crucial part in the rapid adaptability of the pathogen to host plants and underpins its evolutionary potential.

1,341 citations

Journal ArticleDOI
22 Dec 2005-Nature
TL;DR: The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution, and a comparative study with Aspergillus fumigatus and As pergillus oryzae, used in the production of sake, miso and soy sauce, provides new insight into eukaryotic genome evolution and gene regulation.
Abstract: The aspergilli comprise a diverse group of filamentous fungi spanning over 200 million years of evolution. Here we report the genome sequence of the model organism Aspergillus nidulans, and a comparative study with Aspergillus fumigatus, a serious human pathogen, and Aspergillus oryzae, used in the production of sake, miso and soy sauce. Our analysis of genome structure provided a quantitative evaluation of forces driving long-term eukaryotic genome evolution. It also led to an experimentally validated model of mating-type locus evolution, suggesting the potential for sexual reproduction in A. fumigatus and A. oryzae. Our analysis of sequence conservation revealed over 5,000 non-coding regions actively conserved across all three species. Within these regions, we identified potential functional elements including a previously uncharacterized TPP riboswitch and motifs suggesting regulation in filamentous fungi by Puf family genes. We further obtained comparative and experimental evidence indicating widespread translational regulation by upstream open reading frames. These results enhance our understanding of these widely studied fungi as well as provide new insight into eukaryotic genome evolution and gene regulation.

1,297 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

01 Aug 2000
TL;DR: Assessment of medical technology in the context of commercialization with Bioentrepreneur course, which addresses many issues unique to biomedical products.
Abstract: BIOE 402. Medical Technology Assessment. 2 or 3 hours. Bioentrepreneur course. Assessment of medical technology in the context of commercialization. Objectives, competition, market share, funding, pricing, manufacturing, growth, and intellectual property; many issues unique to biomedical products. Course Information: 2 undergraduate hours. 3 graduate hours. Prerequisite(s): Junior standing or above and consent of the instructor.

4,833 citations

Journal ArticleDOI
TL;DR: A short resumé of each fungus in the Top 10 list and its importance is presented, with the intent of initiating discussion and debate amongst the plant mycology community, as well as laying down a bench-mark.
Abstract: The aim of this review was to survey all fungal pathologists with an association with the journal Molecular Plant Pathology and ask them to nominate which fungal pathogens they would place in a 'Top 10' based on scientific/economic importance. The survey generated 495 votes from the international community, and resulted in the generation of a Top 10 fungal plant pathogen list for Molecular Plant Pathology. The Top 10 list includes, in rank order, (1) Magnaporthe oryzae; (2) Botrytis cinerea; (3) Puccinia spp.; (4) Fusarium graminearum; (5) Fusarium oxysporum; (6) Blumeria graminis; (7) Mycosphaerella graminicola; (8) Colletotrichum spp.; (9) Ustilago maydis; (10) Melampsora lini, with honourable mentions for fungi just missing out on the Top 10, including Phakopsora pachyrhizi and Rhizoctonia solani. This article presents a short resume of each fungus in the Top 10 list and its importance, with the intent of initiating discussion and debate amongst the plant mycology community, as well as laying down a bench-mark. It will be interesting to see in future years how perceptions change and what fungi will comprise any future Top 10.

2,807 citations

Journal ArticleDOI
TL;DR: The recent convergence of molecular studies of plant immunity and pathogen infection strategies is revealing an integrated picture of the plant–pathogen interaction from the perspective of both organisms, suggesting novel biotechnological approaches to crop protection.
Abstract: Plants are engaged in a continuous co-evolutionary struggle for dominance with their pathogens. The outcomes of these interactions are of particular importance to human activities, as they can have dramatic effects on agricultural systems. The recent convergence of molecular studies of plant immunity and pathogen infection strategies is revealing an integrated picture of the plant-pathogen interaction from the perspective of both organisms. Plants have an amazing capacity to recognize pathogens through strategies involving both conserved and variable pathogen elicitors, and pathogens manipulate the defence response through secretion of virulence effector molecules. These insights suggest novel biotechnological approaches to crop protection.

2,666 citations

Journal ArticleDOI
TL;DR: This article proposes an elegantly simple multi-seed strategy, called seed-and-vote, for mapping reads to a reference genome, which uses a relatively large number of short seeds extracted from each read and allows all the seeds to vote on the optimal location.
Abstract: Read alignment is an ongoing challenge for the analysis of data from sequencing technologies. This article proposes an elegantly simple multi-seed strategy, called seed-and-vote, for mapping reads to a reference genome. The new strategy chooses the mapped genomic location for the read directly from the seeds. It uses a relatively large number of short seeds (called subreads) extracted from each read and allows all the seeds to vote on the optimal location. When the read length is <160 bp, overlapping subreads are used. More conventional alignment algorithms are then used to fill in detailed mismatch and indel information between the subreads that make up the winning voting block. The strategy is fast because the overall genomic location has already been chosen before the detailed alignment is done. It is sensitive because no individual subread is required to map exactly, nor are individual subreads constrained to map close by other subreads. It is accurate because the final location must be supported by several different subreads. The strategy extends easily to find exon junctions, by locating reads that contain sets of subreads mapping to different exons of the same gene. It scales up efficiently for longer reads.

2,228 citations