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Richard A. Jorgensen

Bio: Richard A. Jorgensen is an academic researcher from University of Arizona. The author has contributed to research in topics: Gene & Cosuppression. The author has an hindex of 42, co-authored 77 publications receiving 21733 citations. Previous affiliations of Richard A. Jorgensen include University of Wisconsin-Madison & University of California, Davis.


Papers
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Journal ArticleDOI
TL;DR: It is concluded that the rDNA sl variants and/or associated loci are under selection in CCII, which demonstrates that Rrn1 and Rrn2 are useful as new genetic markers.
Abstract: Spacer-length (sl) variation in ribosomal RNA gene clusters (rDNA) was surveyed in 502 individual barley plants, including samples from 50 accessions of cultivated barley, 25 accessions of its wild ancestor, and five generations of composite cross II (CCII), an experimental population of barley. In total, 17 rDNA sl phenotypes, made up of 15 different rDNA sl variants, were observed. The 15 rDNA sl variants comprise a complete ladder in which each variant differs in length from adjacent variants by approximately equal to 115 nucleotide pairs. Studies of four rDNA sl variants in an F2 population showed that these variants are located at two unlinked loci, Rrn1 and Rrn2, each with two codominant alleles. Using wheat-barley addition lines, we determined that Rrn1 and Rrn2 are located on chromosomes 6 and 7, respectively. The nonrandom distribution of sl variants between loci suggests that genetic exchange occurs much less frequently between than within the two loci, which demonstrates that Rrn1 and Rrn2 are useful as new genetic markers. Frequencies of rDNA sl phenotypes and variants were monitored over 54 generations in CCII. A phenotype that was originally infrequent in CCII ultimately became predominant, whereas the originally most frequent phenotype decreased drastically in frequency, and all other phenotypes originally present disappeared from the population. We conclude that the sl variants and/or associated loci are under selection in CCII.

4,745 citations

Journal ArticleDOI
Gerald A. Tuskan1, Gerald A. Tuskan2, Stephen P. DiFazio3, Stephen P. DiFazio2, Stefan Jansson4, Joerg Bohlmann5, Igor V. Grigoriev6, Uffe Hellsten6, Nicholas H. Putnam6, Steven G. Ralph5, Stephane Rombauts7, Asaf Salamov6, Jacquie Schein, Lieven Sterck7, Andrea Aerts6, Rishikeshi Bhalerao4, Rishikesh P. Bhalerao8, Damien Blaudez9, Wout Boerjan7, Annick Brun9, Amy M. Brunner10, Victor Busov11, Malcolm M. Campbell12, John E. Carlson13, Michel Chalot9, Jarrod Chapman6, G.-L. Chen2, Dawn Cooper5, Pedro M. Coutinho14, Jérémy Couturier9, Sarah F. Covert15, Quentin C. B. Cronk5, R. Cunningham2, John M. Davis16, Sven Degroeve7, Annabelle Déjardin9, Claude W. dePamphilis13, John C. Detter6, Bill Dirks17, Inna Dubchak18, Inna Dubchak6, Sébastien Duplessis9, Jürgen Ehlting5, Brian E. Ellis5, Karla C Gendler19, David Goodstein6, Michael Gribskov20, Jane Grimwood21, Andrew Groover22, Lee E. Gunter2, Björn Hamberger5, Berthold Heinze, Yrjö Helariutta8, Yrjö Helariutta23, Yrjö Helariutta24, Bernard Henrissat14, D. Holligan15, Robert A. Holt, Wenyu Huang6, N. Islam-Faridi22, Steven J.M. Jones, M. Jones-Rhoades25, Richard A. Jorgensen19, Chandrashekhar P. Joshi11, Jaakko Kangasjärvi24, Jan Karlsson4, Colin T. Kelleher5, Robert Kirkpatrick, Matias Kirst16, Annegret Kohler9, Udaya C. Kalluri2, Frank W. Larimer2, Jim Leebens-Mack15, Jean-Charles Leplé9, Philip F. LoCascio2, Y. Lou6, Susan Lucas6, Francis Martin9, Barbara Montanini9, Carolyn A. Napoli19, David R. Nelson26, C D Nelson22, Kaisa Nieminen24, Ove Nilsson8, V. Pereda9, Gary F. Peter16, Ryan N. Philippe5, Gilles Pilate9, Alexander Poliakov18, J. Razumovskaya2, Paul G. Richardson6, Cécile Rinaldi9, Kermit Ritland5, Pierre Rouzé7, D. Ryaboy18, Jeremy Schmutz21, J. Schrader27, Bo Segerman4, H. Shin, Asim Siddiqui, Fredrik Sterky, Astrid Terry6, Chung-Jui Tsai11, Edward C. Uberbacher2, Per Unneberg, Jorma Vahala24, Kerr Wall13, Susan R. Wessler15, Guojun Yang15, T. Yin2, Carl J. Douglas5, Marco A. Marra, Göran Sandberg8, Y. Van de Peer7, Daniel S. Rokhsar6, Daniel S. Rokhsar17 
15 Sep 2006-Science
TL;DR: The draft genome of the black cottonwood tree, Populus trichocarpa, has been reported in this paper, with more than 45,000 putative protein-coding genes identified.
Abstract: We report the draft genome of the black cottonwood tree, Populus trichocarpa. Integration of shotgun sequence assembly with genetic mapping enabled chromosome-scale reconstruction of the genome. More than 45,000 putative protein-coding genes were identified. Analysis of the assembled genome revealed a whole-genome duplication event; about 8000 pairs of duplicated genes from that event survived in the Populus genome. A second, older duplication event is indistinguishably coincident with the divergence of the Populus and Arabidopsis lineages. Nucleotide substitution, tandem gene duplication, and gross chromosomal rearrangement appear to proceed substantially more slowly in Populus than in Arabidopsis. Populus has more protein-coding genes than Arabidopsis, ranging on average from 1.4 to 1.6 putative Populus homologs for each Arabidopsis gene. However, the relative frequency of protein domains in the two genomes is similar. Overrepresented exceptions in Populus include genes associated with lignocellulosic wall biosynthesis, meristem development, disease resistance, and metabolite transport.

4,025 citations

Journal ArticleDOI
TL;DR: Somatic reversion of plants with white flowers to phenotypically parental violet flowers was associated with a coordinate rise in the steady-state levels of the mRNAs produced by both the endogenous and the introduced CHS genes, indicating that expression of the introduced chalcone synthase gene was not alone sufficient for suppression of endogenous CHS transcript levels.
Abstract: We attempted to overexpress chalcone synthase (CHS) in pigmented petunia petals by introducing a chimeric petunia CHS gene. Unexpectedly, the introduced gene created a block in anthocyanin biosynthesis. Forty-two percent of plants with the introduced CHS gene produced totally white flowers and/or patterned flowers with white or pale nonclonal sectors on a wild-type pigmented background; none of hundreds of transgenic control plants exhibited such phenotypes. Progeny testing of one plant demonstrated that the novel color phenotype co-segregated with the introduced CHS gene; progeny without this gene were phenotypically wild type. The somatic and germinal stability of the novel color patterns was variable. RNase protection analysis of petal RNAs isolated from white flowers showed that, although the developmental timing of mRNA expression of the endogenous CHS gene was not altered, the level of the mRNA produced by this gene was reduced 50-fold from wild-type levels. Somatic reversion of plants with white flowers to phenotypically parental violet flowers was associated with a coordinate rise in the steady-state levels of the mRNAs produced by both the endogenous and the introduced CHS genes. Thus, in the altered white flowers, the expression of both genes was coordinately suppressed, indicating that expression of the introduced CHS gene was not alone sufficient for suppression of endogenous CHS transcript levels. The mechanism responsible for the reversible co-suppression of homologous genes in trans is unclear, but the erratic and reversible nature of this phenomenon suggests the possible involvement of methylation.

2,994 citations

Journal ArticleDOI
Sabeeha S. Merchant1, Simon E. Prochnik2, Olivier Vallon3, Elizabeth H. Harris4, Steven J. Karpowicz1, George B. Witman5, Astrid Terry2, Asaf Salamov2, Lillian K. Fritz-Laylin6, Laurence Maréchal-Drouard7, Wallace F. Marshall8, Liang-Hu Qu9, David R. Nelson10, Anton A. Sanderfoot11, Martin H. Spalding12, Vladimir V. Kapitonov13, Qinghu Ren, Patrick J. Ferris14, Erika Lindquist2, Harris Shapiro2, Susan Lucas2, Jane Grimwood15, Jeremy Schmutz15, Pierre Cardol3, Pierre Cardol16, Heriberto Cerutti17, Guillaume Chanfreau1, Chun-Long Chen9, Valérie Cognat7, Martin T. Croft18, Rachel M. Dent6, Susan K. Dutcher19, Emilio Fernández20, Hideya Fukuzawa21, David González-Ballester22, Diego González-Halphen23, Armin Hallmann, Marc Hanikenne16, Michael Hippler24, William Inwood6, Kamel Jabbari25, Ming Kalanon26, Richard Kuras3, Paul A. Lefebvre11, Stéphane D. Lemaire27, Alexey V. Lobanov17, Martin Lohr28, Andrea L Manuell29, Iris Meier30, Laurens Mets31, Maria Mittag32, Telsa M. Mittelmeier33, James V. Moroney34, Jeffrey L. Moseley22, Carolyn A. Napoli33, Aurora M. Nedelcu35, Krishna K. Niyogi6, Sergey V. Novoselov17, Ian T. Paulsen, Greg Pazour5, Saul Purton36, Jean-Philippe Ral7, Diego Mauricio Riaño-Pachón37, Wayne R. Riekhof, Linda A. Rymarquis38, Michael Schroda, David B. Stern39, James G. Umen14, Robert D. Willows40, Nedra F. Wilson41, Sara L. Zimmer39, Jens Allmer42, Janneke Balk18, Katerina Bisova43, Chong-Jian Chen9, Marek Eliáš44, Karla C Gendler33, Charles R. Hauser45, Mary Rose Lamb46, Heidi K. Ledford6, Joanne C. Long1, Jun Minagawa47, M. Dudley Page1, Junmin Pan48, Wirulda Pootakham22, Sanja Roje49, Annkatrin Rose50, Eric Stahlberg30, Aimee M. Terauchi1, Pinfen Yang51, Steven G. Ball7, Chris Bowler25, Carol L. Dieckmann33, Vadim N. Gladyshev17, Pamela J. Green38, Richard A. Jorgensen33, Stephen P. Mayfield29, Bernd Mueller-Roeber37, Sathish Rajamani30, Richard T. Sayre30, Peter Brokstein2, Inna Dubchak2, David Goodstein2, Leila Hornick2, Y. Wayne Huang2, Jinal Jhaveri2, Yigong Luo2, Diego Martinez2, Wing Chi Abby Ngau2, Bobby Otillar2, Alexander Poliakov2, Aaron Porter2, Lukasz Szajkowski2, Gregory Werner2, Kemin Zhou2, Igor V. Grigoriev2, Daniel S. Rokhsar6, Daniel S. Rokhsar2, Arthur R. Grossman22 
University of California, Los Angeles1, United States Department of Energy2, University of Paris3, Duke University4, University of Massachusetts Medical School5, University of California, Berkeley6, Centre national de la recherche scientifique7, University of California, San Francisco8, Sun Yat-sen University9, University of Tennessee Health Science Center10, University of Minnesota11, Iowa State University12, Genetic Information Research Institute13, Salk Institute for Biological Studies14, Stanford University15, University of Liège16, University of Nebraska–Lincoln17, University of Cambridge18, Washington University in St. Louis19, University of Córdoba (Spain)20, Kyoto University21, Carnegie Institution for Science22, National Autonomous University of Mexico23, University of Münster24, École Normale Supérieure25, University of Melbourne26, University of Paris-Sud27, University of Mainz28, Scripps Research Institute29, Ohio State University30, University of Chicago31, University of Jena32, University of Arizona33, Louisiana State University34, University of New Brunswick35, University College London36, University of Potsdam37, Delaware Biotechnology Institute38, Boyce Thompson Institute for Plant Research39, Macquarie University40, Oklahoma State University Center for Health Sciences41, İzmir University of Economics42, Academy of Sciences of the Czech Republic43, Charles University in Prague44, St. Edward's University45, University of Puget Sound46, Hokkaido University47, Tsinghua University48, Washington State University49, Appalachian State University50, Marquette University51
12 Oct 2007-Science
TL;DR: Analyses of the Chlamydomonas genome advance the understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella.
Abstract: Chlamydomonas reinhardtii is a unicellular green alga whose lineage diverged from land plants over 1 billion years ago. It is a model system for studying chloroplast-based photosynthesis, as well as the structure, assembly, and function of eukaryotic flagella (cilia), which were inherited from the common ancestor of plants and animals, but lost in land plants. We sequenced the approximately 120-megabase nuclear genome of Chlamydomonas and performed comparative phylogenomic analyses, identifying genes encoding uncharacterized proteins that are likely associated with the function and biogenesis of chloroplasts or eukaryotic flagella. Analyses of the Chlamydomonas genome advance our understanding of the ancestral eukaryotic cell, reveal previously unknown genes associated with photosynthetic and flagellar functions, and establish links between ciliopathy and the composition and function of flagella.

2,554 citations

Journal ArticleDOI
TL;DR: The substantial diversification of HATs and HDACs that has occurred since the divergence of plants, animals and fungi suggests a surprising degree of evolutionary plasticity and functional diversification in these core chromatin components.
Abstract: Sequence similarity and profile searching tools were used to analyze the genome sequences of Arabidopsis thaliana, Saccharomyces cerevisiae, Schizosaccharomyces pombe, Caenorhabditis elegans and Drosophila melanogaster for genes encoding three families of histone deacetylase (HDAC) proteins and three families of histone acetyltransferase (HAT) proteins. Plants, animals and fungi were found to have a single member of each of three subfamilies of the GNAT family of HATs, suggesting conservation of these functions. However, major differences were found with respect to sizes of gene families and multi-domain protein structures within other families of HATs and HDACs, indicating substantial evolutionary diversification. Phylogenetic analysis identified a new class of HDACs within the RPD3/HDA1 family that is represented only in plants and animals. A similar analysis of the plant-specific HD2 family of HDACs suggests a duplication event early in dicot evolution, followed by further diversification in the lineage leading to Arabidopsis. Of three major classes of SIR2-type HDACs that are found in animals, fungi have representatives only in one class, whereas plants have representatives only in the other two. Plants possess five CREB-binding protein (CBP)-type HATs compared with one to two in animals and none in fungi. Domain and phylogenetic analyses of the CBP family proteins showed that this family has evolved three distinct types of CBPs in plants. The domain architecture of CBP and TAFII250 families of HATs show significant differences between plants and animals, most notably with respect to bromodomain occurrence and their number. Bromodomain-containing proteins in Arabidopsis differ strikingly from animal bromodomain proteins with respect to the numbers of bromodomains and the other types of domains that are present. The substantial diversification of HATs and HDACs that has occurred since the divergence of plants, animals and fungi suggests a surprising degree of evolutionary plasticity and functional diversification in these core chromatin components.

667 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

Journal ArticleDOI
TL;DR: In this paper, a new vector strategy for the insertion of foreign genes into the genomes of gram negative bacteria not closely related to Escherichia coli was developed, which can utilize any gram negative bacterium as a recipient for conjugative DNA transfer.
Abstract: We have developed a new vector strategy for the insertion of foreign genes into the genomes of gram negative bacteria not closely related to Escherichia coli. The system consists of two components: special E. coli donor strains and derivatives of E. coli vector plasmids. The donor strains (called mobilizing strains) carry the transfer genes of the broad host range IncP–type plasmid RP4 integrated in their chromosomes. They can utilize any gram negative bacterium as a recipient for conjugative DNA transfer. The vector plasmids contain the P–type specific recognition site for mobilization (Mob site) and can be mobilized with high frequency from the donor strains. The mobilizable vectors are derived from the commonly used E. coli vectors pACYC184, pACYC177, and pBR325, and are unable to replicate in strains outside the enteric bacterial group. Therefore, they are widely applicable as transposon carrier replicons for random transposon insertion mutagenesis in any strain into which they can be mobilized but not stably maintained. The vectors are especially useful for site–directed transposon mutagenesis and for site–specific gene transfer in a wide variety of gram negative organisms.

7,278 citations

Journal ArticleDOI
TL;DR: The Carbohydrate-Active Enzyme (CAZy) database is a knowledge-based resource specialized in the enzymes that build and breakdown complex carbohydrates and glycoconjugates and has been used to improve the quality of functional predictions of a number genome projects by providing expert annotation.
Abstract: The Carbohydrate-Active Enzyme (CAZy) database is a knowledge-based resource specialized in the enzymes that build and breakdown complex carbohydrates and glycoconjugates. As of September 2008, the database describes the present knowledge on 113 glycoside hydrolase, 91 glycosyltransferase, 19 polysaccharide lyase, 15 carbohydrate esterase and 52 carbohydrate-binding module families. These families are created based on experimentally characterized proteins and are populated by sequences from public databases with significant similarity. Protein biochemical information is continuously curated based on the available literature and structural information. Over 6400 proteins have assigned EC numbers and 700 proteins have a PDB structure. The classification (i) reflects the structural features of these enzymes better than their sole substrate specificity, (ii) helps to reveal the evolutionary relationships between these enzymes and (iii) provides a convenient framework to understand mechanistic properties. This resource has been available for over 10 years to the scientific community, contributing to information dissemination and providing a transversal nomenclature to glycobiologists. More recently, this resource has been used to improve the quality of functional predictions of a number genome projects by providing expert annotation. The CAZy resource resides at URL: http://www.cazy.org/.

6,028 citations