Transcriptional differentiation across the four cactus host races of Drosophila mojavensis
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PROVIDER: PRJNA176016 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:Local adaptation can play a fundamental role in the isolation of populations. While less well-studied than differentiation in sequence variation, changes in transcriptional variation during speciation also are fundamental to the evolutionary process. Drosophila mojavensis offers an unprecedented opportunity to examine the role of transcriptional differentiation in local adaptation. Drosophila mojavensis is a cactophilic fly composed of four ecologically distinct subspecies that inhabit the deserts of western North America. Each of the four subspecies utilizes necrotic tissue of different cactus host species characterized by distinct chemical profiles. The subspecies in Baja California, Mexico uses Stenocereus gummosus (Agria), in mainland Sonora it uses S. thurberi (Organ Pipe), in the Mojave Desert the host is Ferocactus cylindraceus (Red Barrel) and in Santa Catalina Island, USA, Opuntia littoralis (Prickly Pear) is the host. In this chapter we examine how the adaptation to the different environmental conditions across the four subspecies have shaped their transcriptional profiles. Using complete D. mojavensis genome microarrays we examined the transcriptome of third instar larvae from all four subspecies reared in standard laboratory media free of necrotic cactus-derived compounds. This experimental strategy focused on differences between constitutively expressed genes and not genes induced by necrotic cactus-derived compounds. The subspecies exhibited significant differential expression of genes that likely underlie the adaptation to different cactus hosts, such as detoxification genes (Glutathione S-transferases, Cytochrome P450s and UDP-Glycosyltransferases) and chemosensory genes (Odorant Receptors, Gustatory Receptors and Odorant Binding Proteins). Dataset from Matzkin, L. M. and Markow, T.A. Transcriptional differentiation across the four cactus host races of Drosophila mojavensis. In Speciation: Natural Processes, Genetics and Biodiversity. Edited by Michalak, P. Nova Science Publishers, Inc.
2015-01-01 | GSE41155 | GEO
Project description:Understanding the genetic basis of adaptation to novel environments remains one of the major challenges confronting evolutionary biologists. While newly developed genomic approaches hold considerable promise for addressing this overall question, the relevant tools have not often been available in the most ecologically interesting organisms. Our study organism, Drosophila mojavensis, is a cactophilic Sonoran Desert endemic utilizing four different cactus hosts across its geographic range. Its well-known ecology makes it an attractive system in which to study the evolution of gene expression during adaptation. As a cactophile, D. mojavensis oviposits in the necrotic tissues of cacti, therefore exposing larvae and even adults to the varied and toxic compounds of rotting cacti. We have developed a cDNA microarray of D. mojavensis to examine gene expression associated with cactus host use. Using a population from the Baja California population we examined gene expression differences of third instar larvae when reared in two chemically distinct cactus hosts, agria (Stenocereus gummosus, native host) vs. organpipe (S. thurberi, alternative host). We have observed differential gene expression associated with cactus host use in genes involved in metabolism and detoxification. Keywords: host adaptation, stress response, detoxification
2007-01-24 | GSE5148 | GEO
Project description:In the presence of environmental change, natural selection can shape the transcriptome. Under a scenario of environmental change, genotypes that are better able to modulate gene expression to maximize fitness will tend to be favored. Therefore, it is important to examine gene expression at the population level in order to distinguish random or neutral gene expression variation from the pattern produced by natural selection. This study investigates the natural variation in transcriptional response to a cactus host shift utilizing the mainland Sonora population of Drosophila mojavensis. Drosophila mojavensis is a cactophilic species composed of four cactus host populations endemic to the deserts of North America. Overall, the change in cactus host was associated with a significant reduction in larval viability, as well as the differential expression of 21% of the genome (3,109 genes). Among the genes identified were a set of genes previously known to be involved in xenobiotic metabolism, as well as genes involved in cellular energy production, oxidoreductase/carbohydrate metabolism, structural components and mRNA binding. Interestingly, of the 3,109 genes whose expression was affected by host use, there was a significant overrepresentation of genes that lacked an orthologous call to the D. melanogaster genome, suggesting the possibility of an accelerated rate of evolution in these genes. Of the genes with a significant cactus effect, the majority, 2,264 genes, did not exhibit a significant cactus-by-line interaction. This population level approach facilitated the identification of genes involved in past cactus host shifts. Dataset from Population transcriptomics of cactus host shifts in Drosophila mojavensis, Matzkin, LM. Molecular Ecology.
2012-06-18 | GSE35937 | GEO
Project description:Understanding the genetic basis of adaptation to novel environments remains one of the major challenges confronting evolutionary biologists. While newly developed genomic approaches hold considerable promise for addressing this overall question, the relevant tools have not often been available in the most ecologically interesting organisms. Our study organism, Drosophila mojavensis, is a cactophilic Sonoran Desert endemic utilizing four different cactus hosts across its geographic range. Its well-known ecology makes it an attractive system in which to study the evolution of gene expression during adaptation. As a cactophile, D. mojavensis oviposits in the necrotic tissues of cacti, therefore exposing larvae and even adults to the varied and toxic compounds of rotting cacti. We have developed a cDNA microarray of D. mojavensis to examine gene expression associated with cactus host use. Using a population from the Baja California population we examined gene expression differences of third instar larvae when reared in two chemically distinct cactus hosts, agria (Stenocereus gummosus, native host) vs. organpipe (S. thurberi, alternative host). We have observed differential gene expression associated with cactus host use in genes involved in metabolism and detoxification. The experiment was composed of 5 sets of dye-flips (rep1-5). Larvae were reared in either necrotic agria or organpipe cactus tissues. They were then collected at the third instar stage and its total RNA extracted.
2010-07-01 | E-GEOD-5148 | biostudies-arrayexpress
Project description:Genomic analysis of the four ecologically distinct cactus host populations of Drosophila mojavensis
| PRJNA530196 | ENA
Project description:Population transcriptomics of cactus host shifts in Drosophila mojavensis
| PRJNA152081 | ENA
Project description:Functional genomics of cactus host shifts in Drosophila mojavensis
| PRJNA96547 | ENA
Project description:Although the importance of host plant chemistry in plant-insect interactions is widely accepted, the genetic basis of adaptation to host plants is poorly understood. Here, we investigate transcriptional changes associated with a host plant shift in Drosophila mettleri. While D. mettleri is distributed mainly throughout the Sonoran Desert where it specializes on columnar cacti (Carnegiea gigantea and Pachycereus pringleii), a population on Santa Catalina Island has shifted to coastal prickly pear cactus (Opuntia littoralis). We compared gene expression of larvae from the Sonoran Desert and Santa Catalina Island when reared on saguaro (C. gigantea), coastal prickly pear, and laboratory food. Consistent with expectations based on the complexity and toxicity of cactus relative to laboratory food, within population comparisons between larvae reared on these food sources revealed transcriptional differences in detoxification and other metabolic pathways. The majority of transcriptional differences between populations on the cactus hosts were independent of the rearing environment, and included a disproportionate number of genes involved in processes relevant to host plant adaptation (e.g. detoxification, central metabolism, and chemosensory pathways). Comparisons of transcriptional reaction norms between the two populations revealed extensive shared plasticity that likely allowed colonization of coastal prickly pear on Santa Catalina Island. We also found that while plasticity may have facilitated subsequent adaptive divergence in gene expression between populations, the majority of genes that differed in expression on the novel host were not transcriptionally plastic in the presumed ancestral state.
2015-09-03 | GSE71110 | GEO
Project description:BackgroundRelationships between an organism and its environment can be fundamental in the understanding how populations change over time and species arise. Local ecological conditions can shape variation at multiple levels, among these are the evolutionary history and trajectories of coding genes. This study examines the rate of molecular evolution at protein-coding genes throughout the genome in response to host adaptation in the cactophilic Drosophila mojavensis. These insects are intimately associated with cactus necroses, developing as larvae and feeding as adults in these necrotic tissues. Drosophila mojavensis is composed of four isolated populations across the deserts of western North America and each population has adapted to utilize different cacti that are chemically, nutritionally, and structurally distinct.ResultsHigh coverage Illumina sequencing was performed on three previously unsequenced populations of D. mojavensis. Genomes were assembled using the previously sequenced genome of D. mojavensis from Santa Catalina Island (USA) as a template. Protein coding genes were aligned across all four populations and rates of protein evolution were determined for all loci using a several approaches.ConclusionsLoci that exhibited elevated rates of molecular evolution tend to be shorter, have fewer exons, low expression, be transcriptionally responsive to cactus host use and have fixed expression differences across the four cactus host populations. Fast evolving genes were involved with metabolism, detoxification, chemosensory reception, reproduction and behavior. Results of this study give insight into the process and the genomic consequences of local ecological adaptation.
| S-EPMC6790045 | biostudies-literature
Project description:Although the importance of host plant chemistry in plant-insect interactions is widely accepted, the genetic basis of adaptation to host plants is poorly understood. Here, we investigate transcriptional changes associated with a host plant shift in Drosophila mettleri. While D. mettleri is distributed mainly throughout the Sonoran Desert where it specializes on columnar cacti (Carnegiea gigantea and Pachycereus pringleii), a population on Santa Catalina Island has shifted to coastal prickly pear cactus (Opuntia littoralis). We compared gene expression of larvae from the Sonoran Desert and Santa Catalina Island when reared on saguaro (C. gigantea), coastal prickly pear, and laboratory food. Consistent with expectations based on the complexity and toxicity of cactus relative to laboratory food, within population comparisons between larvae reared on these food sources revealed transcriptional differences in detoxification and other metabolic pathways. The majority of transcriptional differences between populations on the cactus hosts were independent of the rearing environment, and included a disproportionate number of genes involved in processes relevant to host plant adaptation (e.g. detoxification, central metabolism, and chemosensory pathways). Comparisons of transcriptional reaction norms between the two populations revealed extensive shared plasticity that likely allowed colonization of coastal prickly pear on Santa Catalina Island. We also found that while plasticity may have facilitated subsequent adaptive divergence in gene expression between populations, the majority of genes that differed in expression on the novel host were not transcriptionally plastic in the presumed ancestral state. mRNA profiles of third instar larvae from two different populations reared on three food types was sequenced on two lanes of an Illumina HiSeq 2000 Please note that the de novo assembly gives names to transcripts with the following convention: compXXX_cX_seqX. The first two identifiers (compXX_cX) are equivalent to a gene while the 'seq' identifier might refer to different isoforms or splice variants, etc. Therefore, for example, a gene might be comp123_c0, and this could have multiple sequences corresponding to different isoforms or splice variants. Since the analysis was carried out at the gene level, the program internally merged the multiple sequences together for each gene to generate the count matrix (AllGenesint.counts.matrix.txt) (i.e. it only includes comp123_c0), while the file from the assembly (i.e. Trinity.fasta) also include the individual sequences with the 'seq' identifier.
2015-09-03 | E-GEOD-71110 | biostudies-arrayexpress