Thermal evolution of gene expression profiles in Drosophila subobscura
Open Access
- 19 March 2007
- journal article
- research article
- Published by Springer Science and Business Media LLC in BMC Evolutionary Biology
- Vol. 7 (1), 42
- https://doi.org/10.1186/1471-2148-7-42
Abstract
Despite its pervasiveness, the genetic basis of adaptation resulting in variation directly or indirectly related to temperature (climatic) gradients is poorly understood. By using 3-fold replicated laboratory thermal stocks covering much of the physiologically tolerable temperature range for the temperate (i.e., cold tolerant) species Drosophila subobscura we have assessed whole-genome transcriptional responses after three years of thermal adaptation, when the populations had already diverged for inversion frequencies, pre-adult life history components, and morphological traits. Total mRNA from each population was compared to a reference pool mRNA in a standard, highly replicated two-colour competitive hybridization experiment using cDNA microarrays. A total of 306 (6.6%) cDNA clones were identified as 'differentially expressed' (following a false discovery rate correction) after contrasting the two furthest apart thermal selection regimes (i.e., 13°C vs . 22°C), also including four previously reported candidate genes for thermotolerance in Drosophila (Hsp26, Hsp68, Fst, and Treh). On the other hand, correlated patterns of gene expression were similar in cold- and warm-adapted populations. Analysis of functional categories defined by the Gene Ontology project point to an overrepresentation of genes involved in carbohydrate metabolism, nucleic acids metabolism and regulation of transcription among other categories. Although the location of differently expressed genes was approximately at random with respect to chromosomes, a physical mapping of 88 probes to the polytene chromosomes of D. subobscura has shown that a larger than expected number mapped inside inverted chromosomal segments. Our data suggest that a sizeable number of genes appear to be involved in thermal adaptation in Drosophila, with a substantial fraction implicated in metabolism. This apparently illustrates the formidable challenge to understanding the adaptive evolution of complex trait variation. Furthermore, some clustering of genes within inverted chromosomal sections was detected. Disentangling the effects of inversions will be obviously required in any future approach if we want to identify the relevant candidate genes.Keywords
This publication has 72 references indexed in Scilit:
- Global Warming: Fly Populations Are Responding Rapidly to Climate ChangeCurrent Biology, 2007
- Inbreeding by Environmental Interactions Affect Gene Expression in Drosophila melanogasterGenetics, 2006
- Uncovering evolutionary patterns of gene expression using microarraysTrends in Ecology & Evolution, 2006
- Statistical significance for genomewide studiesProceedings of the National Academy of Sciences of the United States of America, 2003
- Adaptation of Drosophila to temperature extremes: bringing together quantitative and molecular approachesJournal of Thermal Biology, 2003
- The Genome Sequence of Drosophila melanogasterScience, 2000
- Antagonistic Pleiotropic Effect of Second-Chromosome Inversions on Body Size and Early Life-History Traits in Drosophila buzzatiiEvolution, 1998
- Density-dependent natural selection inDrosophila: Trade-offs between larval food acquisition and utilizationEvolutionary Ecology, 1996
- Thermal evolution of pre‐adult life history traits in Drosophila melanogasterJournal of Evolutionary Biology, 1994
- Transcriptional and translational study of the Drosophila subobscura hsp83 gene in normal and heat-shock conditionsGenome, 1993