Program Book - 27th Fungal Genetics Conference

FULL POSTER SESSION ABSTRACTSComparative and Functional Genomics221. A novel approach for functional analysis of genes in the rice blast fungus. Sook-Young Park 1 , Jaehyuk Choi 1 , Seongbeom Kim 1 , Jongbum Jeon 1 ,Jaeyoung Choi 1 , Seomun Kwon 1 , Dayoung Lee 1 , Aram Huh 1 , Miho Shin 1 , Junhyun Jeon 1 , Seogchan Kang 2 , Yong-Hwan Lee 1 . 1) Dept. of AgriculturalBiotechnology, Seoul National University, Seoul 151-921, South Korea; 2) Dept. of Plant Pathology & Environmental Microbiology, The Pennsylvania StateUniversity, University Park, PA 16802, USA.Null mutants generated by targeted gene replacement are frequently used to reveal function of the genes in fungi. However, targeted gene deletionsmay be difficult to obtain or it may not be applicable, such as in the case of redundant or lethal genes. Constitutive expression system could be analternative to avoid these difficulties and to provide new platform in fungal functional genomics research. Here we developed a novel platform forfunctional analysis genes in Magnaporthe oryzae by constitutive expression under a strong promoter. Employing a binary vector (pGOF), carrying EF1bpromoter, we generated a total of 4,432 transformants by Agrobacterium tumafaciens-mediated transformation. We have analyzed a subset of 54transformants that have the vector inserted in the promoter region of individual genes, at distances ranging from 44 to 1,479 bp. These transformantsshowed increased transcript levels of the genes that are found immediately adjacent to the vector, compared to those of wild type. Ten transformantsshowed higher levels of expression relative to the wild type not only in mycelial stage but also during infection-related development. Two transformantsthat T-DNA was inserted in the promotor regions of putative lethal genes, MoRPT4 and MoDBP5, showed decreased conidiation and pathogenicity,respectively. We also characterized two transformants that T-DNA was inserted in functionally redundant genes encoding alpha-glucosidase and alphamannosidase.These transformants also showed decreased mycelial growth and pathogenicity, implying successful application of this platform infunctional analysis of the genes. Our data also demonstrated that comparative phenotypic analysis under over-expression and suppression of geneexpression could prove a highly efficient system for functional analysis of the genes. Our over-expressed transformant library would be a valuable resourcefor functional characterization of the redundant or lethal genes in M. oryzae and this system may be applicable in other fungi.222. Distribution and evolution of transposable elements in the Magnaporthe oryzae/grisea clade. Joelle Amselem 1,2 , Ludovic Mallet 1,3 , HeleneChiapello 3,4 , Cyprien Guerin 3 , Marc-Henri Lebrun 2 , Didier Tharreau 5 , Elisabeth Fournier 6 . 1) INRA, URGI, Versailles, France; 2) INRA, UMR BIOGER, Thiverval-Grignon, France; 3) INRA, UR MIG, Jouy-en-Josas, France; 4) INRA, UR BIA, Castanet-Tolosan, France; 5) CIRAD, UMR BGPI, Montpellier, France; 6) INRA,UMR BGPI, Montpellier, France.Magnaporthe oryzae is a successful pathogen of crop plants and a major threat for food production. This species gathers pathogens of differentPoaceaes, and causes the main fungal disease of rice worldwide and severe epidemics on wheat in South America. The evolutionary genomics ofMagnaporthe oryzae project aims at characterizing genomic determinants and evolutionary events involved in the adaptation of fungus to different hostplants. Such evolution may rely on variations in Transposable Elements (TEs) and gene content as well as modification of coding and regulatory sequences.Indeed, TEs are essential for shaping genomes and are a source of mutations and genome re-organizations. We performed a comparative analysis of TEs in9 isolates from the M. oryzae/grisea clade differing in their host specificity using a reference TEs consensus library (Mg7015_Refs_TE) made from M. grisea70-15 reference genome. We used REPET pipelines (http://urgi.versailles.inra.fr/Tools/REPET) to detect ab initio and classify TEs in M. grisea 70-15according to functional features (LTR, ITR, RT, transposase, etc.). After manual curation on consensus provided by the TEdenovo pipeline, we used theresulting consensus of TE families (Mg7015_Refs_TE) to annotate the 9 genome copies including nested and degenerated ones using TEannot pipeline. Wewill present results obtained for Mg7015_Refs_TE classification, their annotation, distribution along the genome and preliminary results provided bycomparison in M. oryzae/grisea species studied regarding correlation with phylogeny and host specificity.223. Alternative structural annotation of Aspergillus oryzae and Aspergillus nidulans based on RNA-Seq evidence. Gustavo C Cerqueira 1 , Brian Haas 1 ,Marcus Chibucos 2 , Martha Arnaud 3 , Christopher Sibthorp 4 , Mark X Caddick 4 , Kazuhiro Iwashita 5 , Gavin Sherlock 3 , Jennifer Wortman 1 . 1) Broad Institute,Boston, MA; 2) Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, USA; 3) Department of Genetics, Stanford UniversityMedical School, Stanford, USA; 4) School of Biological Sciences, University of Liverpool, Liverpool, United Kingdom; 5) National Research Institute ofBrewing, Hiroshima, Japan.The correct structural annotation of genes is fundamental to downstream functional genomics approaches. Genes undetected by gene predictionalgorithms, incorrect gene boundaries, misplaced or missing exons and wrongly merged genes can jeopardize attempts to produce a comprehensivecatalog of an organism’s metabolic capabilities. We are currently working toward generating alternative and improved structural annotation of Aspergillusoryzae and Aspergillus nidulans. Our approach consists of assembling partial transcript sequences from RNA-Seq data, aligning transcript assemblies totheir respective genomic loci and finally adjusting the gene models according to the new trancript evidence. Novel putative genes were defined based ontranscriptionally active regions containing splice junctions and open reading frames. Gene loci having transcripts suggesting alternative splicing variantswere reported. The nucleotide composition in the vicinity of splicing sites was re-evaluated in the light of the newly defined exons-introns boundaries. Themodified structural annotation was compared to the original structural annotation of these genomes and alternative gene models derived fromapproaches similar to those presented here. The improved gene models are available through the Aspergillus genome database (http://http://www.aspergillusgenome.org).224. Improved Gene Ontology annotation for biofilm formation, filamentous growth and phenotypic switching in Candida albicans. Diane O. Inglis,Marek S. Skrzypek, Arnaud B. Martha, Binkley Jonathan, Prachi Shah, Farrell Wymore, Gavin Sherlock. Department of Genetics, Stanford University,Stanford, CA.The opportunistic fungal pathogen, Candida albicans, is a significant medical threat, especially for immunocompromised patients. Experimental researchhas focused on specific areas of C. albicans biology with the goal of understanding the multiple factors that contribute to its pathogenic potential. Some ofthese factors include cell adhesion, invasive or filamentous growth and the formation of drug resistant biofilms. The Candida Genome Database (CGD,http://www.candidagenome.org/) is an internet-based resource that provides centralized access to genomic sequence data and manually curatedfunctional information about genes and proteins of the fungal pathogen Candida albicans and other Candida species. The Gene Ontology (GO;www.geneontology.org) is a standardized vocabulary that the Candida Genome Database (CGD; www.candidagenome.org) and other groups use todescribe the function of gene products. To improve the breadth and accuracy of pathogenicity-related gene product descriptions and to facilitate thedescription of as-yet uncharacterized but potential pathogenicity-related genes in Candida species, CGD has undertaken a three-part project: first, theaddition of terms to the Biological Process branch of the GO to improve the description of fungal-related processes; second, manual recuration of geneproduct annotations in CGD to use the improved GO vocabulary; and third, computational ortholog-based transfer of GO annotations from experimentally27th Fungal Genetics Conference | 175