Global expression analysis of the brown alga Ectocarpus siliculosus (Phaeophyceae) reveals large-scale reprogramming of the transcriptome in response to abiotic stress
1 UPMC Univ Paris 6, UMR 7139 Végétaux marins et Biomolécules, Station Biologique, 29680 Roscoff, France
2 CNRS, UMR 7139 Végétaux marins et Biomolécules, Station Biologique, 29680 Roscoff, France
3 CEA, DSV, Institut de Génomique, Génoscope, rue Gaston Crémieux, CP5706, 91057 Evry, France
4 CNRS, UMR 8030 Génomique métabolique des genomes, rue Gaston Crémieux, CP5706, 91057 Evry, France
5 Université d'Evry, UMR 8030 Génomique métabolique des genomes, 91057 Evry, France
6 SIG-FR 2424 CNRS UPMC, Station Biologique, 29680 Roscoff, France
7 Center for Biotechnology (CeBiTec), University of Bielefeld, 33594 Bielefeld, Germany
8 German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany
9 VIB Department of Plant Systems Biology, Ghent University, 9052 Ghent, Belgium
Genome Biology 2009, 10:R66 doi:10.1186/gb-2009-10-6-r66Published: 16 June 2009
Brown algae (Phaeophyceae) are phylogenetically distant from red and green algae and an important component of the coastal ecosystem. They have developed unique mechanisms that allow them to inhabit the intertidal zone, an environment with high levels of abiotic stress. Ectocarpus siliculosus is being established as a genetic and genomic model for the brown algal lineage, but little is known about its response to abiotic stress.
Here we examine the transcriptomic changes that occur during the short-term acclimation of E. siliculosus to three different abiotic stress conditions (hyposaline, hypersaline and oxidative stress). Our results show that almost 70% of the expressed genes are regulated in response to at least one of these stressors. Although there are several common elements with terrestrial plants, such as repression of growth-related genes, switching from primary production to protein and nutrient recycling processes, and induction of genes involved in vesicular trafficking, many of the stress-regulated genes are either not known to respond to stress in other organisms or are have been found exclusively in E. siliculosus.
This first large-scale transcriptomic study of a brown alga demonstrates that, unlike terrestrial plants, E. siliculosus undergoes extensive reprogramming of its transcriptome during the acclimation to mild abiotic stress. We identify several new genes and pathways with a putative function in the stress response and thus pave the way for more detailed investigations of the mechanisms underlying the stress tolerance ofbrown algae.