RNA-Seq reveals genotype-specific molecular responses to water deficit in eucalyptus

BMC Genomics

Research Article

Jean-Marc Gion¹  Emilie Villar²  Christophe Plomion³  Christophe Klopp⁴  Céline Noirot⁴  Matias Kirst⁵  Evandro Novaes⁶ 

[1] CIRAD, UMR AGAP, Campus de Baillarguet TA 10C, F-34398, Montpellier Cedex 5, France;INRA, UMR1202 BIOGECO, F-33610, Cestas, France;CIRAD, UMR AGAP, Campus de Baillarguet TA 10C, F-34398, Montpellier Cedex 5, France;INRA, UMR1202 BIOGECO, F-33610, Cestas, France;CRDPI, BP1291, Pointe Noire, Congo;INRA, UMR1202 BIOGECO, F-33610, Cestas, France;Université de Bordeaux, UMR1202 BIOGECO, F-33610, Cestas, France;Plateforme bioinformatique Genotoul, UR875 Biométrie et Intelligence Artificielle, INRA, 31326, Castanet-Tolosan, France;School of Forest Resources and Conservation, University of Florida, PO Box 110410, Gainesville, USA;School of Forest Resources and Conservation, University of Florida, PO Box 110410, Gainesville, USA;Universidade Federal de Goiás, CEP 74690-900, Caixa Postal 131, Goiânia, Brazil;

关键词: Water Deficit;    Soil Water Content;    Digital Gene Expression;    Watering Regime;    Productive Genotype;   

DOI  :  10.1186/1471-2164-12-538

 received in 2011-07-19, accepted in 2011-11-02,  发布年份 2011

来源: Springer

【 摘 要 】

BackgroundIn a context of climate change, phenotypic plasticity provides long-lived species, such as trees, with the means to adapt to environmental variations occurring within a single generation. In eucalyptus plantations, water availability is a key factor limiting productivity. However, the molecular mechanisms underlying the adaptation of eucalyptus to water shortage remain unclear. In this study, we compared the molecular responses of two commercial eucalyptus hybrids during the dry season. Both hybrids differ in productivity when grown under water deficit.ResultsPyrosequencing of RNA extracted from shoot apices provided extensive transcriptome coverage - a catalog of 129,993 unigenes (49,748 contigs and 80,245 singletons) was generated from 398 million base pairs, or 1.14 million reads. The pyrosequencing data enriched considerably existing Eucalyptus EST collections, adding 36,985 unigenes not previously represented. Digital analysis of read abundance in 14,460 contigs identified 1,280 that were differentially expressed between the two genotypes, 155 contigs showing differential expression between treatments (irrigated vs. non irrigated conditions during the dry season), and 274 contigs with significant genotype-by-treatment interaction. The more productive genotype displayed a larger set of genes responding to water stress. Moreover, stress signal transduction seemed to involve different pathways in the two genotypes, suggesting that water shortage induces distinct cellular stress cascades. Similarly, the response of functional proteins also varied widely between genotypes: the most productive genotype decreased expression of genes related to photosystem, transport and secondary metabolism, whereas genes related to primary metabolism and cell organisation were over-expressed.ConclusionsFor the most productive genotype, the ability to express a broader set of genes in response to water availability appears to be a key characteristic in the maintenance of biomass growth during the dry season. Its strategy may involve a decrease of photosynthetic activity during the dry season associated with resources reallocation through major changes in the expression of primary metabolism associated genes. Further efforts will be needed to assess the adaptive nature of the genes highlighted in this study.

【 授权许可】

Unknown   
© Villar et al; licensee BioMed Central Ltd. 2011. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.