wDBTF: an integrated database resource for studying wheat transcription factor families

BackgroundTranscription factors (TFs) regulate gene expression by interacting with promoters of their target genes and are classified into families based on their DNA-binding domains. Genes coding for TFs have been identified in the sequences of model plant genomes. The rice (Oryza sativa spp. japonica) genome contains 2,384 TF gene models, which represent the mRNA transcript of a locus, classed into 63 families.ResultsWe have created an extensive list of wheat (Triticum aestivum L) TF sequences based on sequence homology with rice TFs identified and classified in the Database of Rice Transcription Factors (DRTF). We have identified 7,112 wheat sequences (contigs and singletons) from a dataset of 1,033,960 expressed sequence tag and mRNA (ET) sequences available. This number is about three times the number of TFs in rice so proportionally is very similar if allowance is made for the hexaploidy of wheat. Of these sequences 3,820 encode gene products with a DNA-binding domain and thus were confirmed as potential regulators. These 3,820 sequences were classified into 40 families and 84 subfamilies and some members defined orphan families. The results were compiled in the Database of Wheat Transcription Factor (wDBTF), an inventory available on the web http://wwwappli.nantes.inra.fr:8180/wDBFT/. For each accession, a link to its library source and its Affymetrix identification number is provided. The positions of Pfam (protein family database) motifs were given when known.ConclusionswDBTF collates 3,820 wheat TF sequences validated by the presence of a DNA-binding domain out of 7,112 potential TF sequences identified from publicly available gene expression data. We also incorporated in silico expression data on these TFs into the database. Thus this database provides a major resource for systematic studies of TF families and their expression in wheat as illustrated here in a study of DOF family members expressed during seed development.

[1]  D. Janies,et al.  GRASSIUS: A Platform for Comparative Regulatory Genomics across the Grasses1[W][OA] , 2008, Plant Physiology.

[2]  G. Xue,et al.  Members of the Dof transcription factor family in Triticum aestivum are associated with light-mediated gene regulation , 2009, Functional & Integrative Genomics.

[3]  Ge Gao,et al.  DRTF: a database of rice transcription factors , 2006, Bioinform..

[4]  Di Liu,et al.  DATF: a database of Arabidopsis transcription factors , 2005, Bioinform..

[5]  M. Esaka,et al.  The Dof domain, a zinc finger DNA-binding domain conserved only in higher plants, truly functions as a Cys2/Cys2 Zn finger domain. , 2004, The Plant journal : for cell and molecular biology.

[6]  S. Yanagisawa The Dof family of plant transcription factors. , 2002, Trends in plant science.

[7]  Xin Chen,et al.  PlantTFDB: a comprehensive plant transcription factor database , 2007, Nucleic Acids Res..

[8]  Ramana V. Davuluri,et al.  AGRIS: Arabidopsis Gene Regulatory Information Server, an information resource of Arabidopsis cis-regulatory elements and transcription factors , 2003, BMC Bioinformatics.

[9]  Lijuan Cong,et al.  Characterization of soybean genomic features by analysis of its expressed sequence tags , 2004, Theoretical and Applied Genetics.

[10]  C. Feuillet,et al.  Characterizing the composition and evolution of homoeologous genomes in hexaploid wheat through BAC-end sequencing on chromosome 3B. , 2006, The Plant journal : for cell and molecular biology.

[11]  J. Riechmann,et al.  A genomic perspective on plant transcription factors. , 2000, Current opinion in plant biology.

[12]  G. Ingram,et al.  Engrailed-ZmOCL1 fusions cause a transient reduction of kernel size in maize , 2005, Plant Molecular Biology.

[13]  G. Xue,et al.  Genome-wide identification and expression analysis of the NF-Y family of transcription factors in Triticum aestivum , 2007, Plant Molecular Biology.

[14]  P. Martre,et al.  Nucleotide Polymorphism in the Wheat Transcriptional Activator Spa Influences Its Pattern of Expression and Has Pleiotropic Effects on Grain Protein Composition, Dough Viscoelasticity, and Grain Hardness[W][OA] , 2009, Plant Physiology.

[15]  F. Guillon,et al.  Integrating genes and phenotype: a wheat–Arabidopsis–rice glycosyltransferase database for candidate gene analyses , 2009, Functional & Integrative Genomics.

[16]  M. A. Moreno-Risueno,et al.  The family of DOF transcription factors: from green unicellular algae to vascular plants , 2007, Molecular Genetics and Genomics.

[17]  M. Mena,et al.  An endosperm-specific DOF protein from barley, highly conserved in wheat, binds to and activates transcription from the prolamin-box of a native B-hordein promoter in barley endosperm. , 1998, The Plant journal : for cell and molecular biology.

[18]  R. R. Samaha,et al.  Arabidopsis transcription factors: genome-wide comparative analysis among eukaryotes. , 2000, Science.

[19]  Pierre Sourdille,et al.  Molecular Basis of Evolutionary Events That Shaped the Hardness Locus in Diploid and Polyploid Wheat Species (Triticum and Aegilops)w⃞ , 2005, The Plant Cell Online.

[20]  M. A. Moreno-Risueno,et al.  The HvDOF19 transcription factor mediates the abscisic acid-dependent repression of hydrolase genes in germinating barley aleurone. , 2007, The Plant journal : for cell and molecular biology.

[21]  Z. Ni,et al.  Isolation and characterization of TaDof1 transcription factor in wheat (Triticum. aestivum. L) , 2005, DNA sequence : the journal of DNA sequencing and mapping.

[22]  J. Thompson,et al.  The CLUSTAL_X windows interface: flexible strategies for multiple sequence alignment aided by quality analysis tools. , 1997, Nucleic acids research.

[23]  S. Yanagisawa,et al.  Diversity and similarity among recognition sequences of Dof transcription factors. , 1999, The Plant journal : for cell and molecular biology.

[24]  P. Langridge,et al.  Comparative transcriptomics in the Triticeae , 2009, BMC Genomics.

[25]  R. S. Conlan,et al.  Transcription activation mediated by the bZIP factor SPA on the endosperm box is modulated by ESBF-1 in vitro. , 1999, The Plant journal : for cell and molecular biology.

[26]  Y. Yamazaki,et al.  Discrimination of homoeologous gene expression in hexaploid wheat by SNP analysis of contigs grouped from a large number of expressed sequence tags , 2003, Molecular Genetics and Genomics.

[27]  Alexander E. Kel,et al.  TRANSFAC®: transcriptional regulation, from patterns to profiles , 2003, Nucleic Acids Res..

[28]  Clare Mills,et al.  Transcriptome analysis of grain development in hexaploid wheat , 2008, BMC Genomics.

[29]  G. Barker,et al.  Measuring global gene expression in polyploidy; a cautionary note from allohexaploid wheat , 2007, Functional & Integrative Genomics.

[30]  Jesús Vicente-Carbajosa,et al.  Genome-wide comparative phylogenetic analysis of the rice and Arabidopsis Dof gene families , 2003, BMC Evolutionary Biology.

[31]  Tieyan Liu,et al.  Transcription Factors in Rice: A Genome-wide Comparative Analysis between Monocots and Eudicots , 2005, Plant Molecular Biology.

[32]  John Quackenbush,et al.  The TIGR Gene Indices: reconstruction and representation of expressed gene sequences , 2000, Nucleic Acids Res..

[33]  M. Mena,et al.  SAD: a new DOF protein from barley that activates transcription of a cathepsin B-like thiol protease gene in the aleurone of germinating seeds. , 2003, The Plant journal : for cell and molecular biology.

[34]  Uri Alon,et al.  Coding limits on the number of transcription factors , 2006, BMC Genomics.

[35]  M. Pfaffl,et al.  Determination of stable housekeeping genes, differentially regulated target genes and sample integrity: BestKeeper – Excel-based tool using pair-wise correlations , 2004, Biotechnology Letters.

[36]  J. Riechmann,et al.  Transcriptional Regulation: a Genomic Overview , 2002, The arabidopsis book.

[37]  Structure and organization of the wheat genome – the number of genes in the hexaploid wheat genome , 2008 .

[38]  S. Praud,et al.  Single nucleotide polymorphism, genetic mapping, and expression of genes coding for the DOF wheat prolamin-box binding factor , 2006, Functional & Integrative Genomics.

[39]  Roderic D. M. Page,et al.  TreeView: an application to display phylogenetic trees on personal computers , 1996, Comput. Appl. Biosci..

[40]  A. Paolacci,et al.  Molecular and phylogenetic analysis of MADS-box genes of MIKC type and chromosome location of SEP-like genes in wheat (Triticum aestivum L.) , 2007, Molecular Genetics and Genomics.

[41]  M. Maekawa,et al.  Structural and functional properties of Viviparous1 genes in dormant wheat. , 2008, Genes & genetic systems.

[42]  C. Nakamura,et al.  Differential regulation of transcript accumulation and alternative splicing of a DREB2 homolog under abiotic stress conditions in common wheat. , 2006, Genes & genetic systems.

[43]  Z. Ni,et al.  Isolation and characterization of genes encoding Myb transcription factor in wheat (Triticum aestivem L.) , 2005 .

[44]  S. Chen,et al.  The soybean Dof-type transcription factor genes, GmDof4 and GmDof11, enhance lipid content in the seeds of transgenic Arabidopsis plants. , 2007, The Plant journal : for cell and molecular biology.

[45]  Francesc X. Avilés,et al.  TrSDB: a proteome database of transcription factors , 2004, Nucleic Acids Res..

[46]  M. Boguski,et al.  dbEST — database for “expressed sequence tags” , 1993, Nature Genetics.