title: Transcriptome Profiling of WildArachisfrom Water-Limited Environments Uncovers Drought Tolerance Candidate Genes.
abstract: Peanut (Arachis hypogaeaL.) is an important legume cultivated mostly in drought-prone areas where its productivity can be limited by water scarcity. The development of more drought-tolerant varieties is, therefore, a priority for peanut breeding programs worldwide. In contrast to cultivated peanut, wild relatives have a broader genetic diversity and constitute a rich source of resistance/tolerance alleles to biotic and abiotic stresses. The present study takes advantage of this diversity to identify drought-responsive genes by analyzing the expression profile of two wild species,Arachis duranensisandArachis magna(AA and BB genomes, respectively), in response to progressive water deficit in soil. Data analysis from leaves and roots ofA. duranensis(454 sequencing) andA. magna(suppression subtractive hybridization (SSH)) stressed and control complementary DNA (cDNA) libraries revealed several differentially expressed genes in silico, and 44 of them were selected for further validation by quantitative RT-PCR (qRT-PCR). This allowed the identification of drought-responsive candidate genes, such as Expansin, Nitrilase,NAC, andbZIPtranscription factors, displaying significant levels of differential expression during stress imposition in both species. This is the first report on identification of differentially expressed genes under drought stress and recovery in wildArachisspecies. The generated transcriptome data, besides being a valuable resource for gene discovery, will allow the characterization of new alleles and development of molecular markers associated with drought responses in peanut. These together constitute important tools for the peanut breeding program and also contribute to a better comprehension of gene modulation in response to water deficit and rehydration.
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Ana C M
authors.initials: AC
authors.lastname: Brasileiro
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil ; Embrapa Semiárido, Petrolina, PE Brazil.
authors.forename: Carolina V
authors.initials: CV
authors.lastname: Morgante
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Ana C G
authors.initials: AC
authors.lastname: Araujo
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Soraya C M
authors.initials: SC
authors.lastname: Leal-Bertioli
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Amanda K
authors.initials: AK
authors.lastname: Silva
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Andressa C Q
authors.initials: AC
authors.lastname: Martins
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Christina C
authors.initials: CC
authors.lastname: Vinson
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil ; CONAB, Brasília, DF Brazil.
authors.forename: Candice M R
authors.initials: CM
authors.lastname: Santos
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Orzenil
authors.initials: O
authors.lastname: Bonfim
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Roberto C
authors.initials: RC
authors.lastname: Togawa
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Mario A P
authors.initials: MA
authors.lastname: Saraiva
authors.affiliation: Universidade de Brasília, Campus I, Brasília, DF Brazil.
authors.forename: David J
authors.initials: DJ
authors.lastname: Bertioli
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Parque Estação Biológica, 02372 Final W5 Norte, Brasília, DF Brazil.
authors.forename: Patricia M
authors.initials: PM
authors.lastname: Guimaraes
keywords: 454 Sequencing; Differential gene expression; Dry-down; Peanut wild relatives; SSH libraries; qRT-PCR