Dataset Information

Proteomic profiling of thermal acclimation in Drosophila melanogaster

ABSTRACT: Proteomic response of adult Drosophila melanogaster acclimated at three contrasted thermal conditions (11, 25 and 31 degree Celsius) investigated by 2D-DIGE experiment. Thermal acclimation drastically alters thermotolerance of ectotherms, but the mechanisms determining this plastic response are not fully understood. The present study investigates the proteomic response (2D-DIGE) of adult Drosophila melanogaster acclimated at 11, 25 or 31 °C. As expected 11 °C-acclimation improved cold tolerance and 31 °C-acclimation improved heat tolerance. We hypothesized that the marked organismal responses to acclimation could be detected at the proteomic level assuming that changes in the abundance of specific proteins are linked to the physiological changes underlying the phenotypic response. The 31 °C-acclimated flies displayed a particular divergent proteomic profile where molecular chaperones made up a large number of the proteins that were modulated during heat acclimation. Many other proteins showed significant modulation during acclimation including proteins involved in iron ion and cell redox homeostasis, carbohydrate and energy metabolism, chromatin remodeling and translation, and contractile machinery. Interestingly the changes in protein abundance were often unrelated to transcriptional activity of the genes coding for the proteins, except for the most strongly expressed proteins (e.g. Hsp70). The 11 °C-acclimation evoked weak proteomic response despite the marked effect on the organismal phenotype. Thus the acquired cold tolerance observed here may involve regulatory process such as posttranslational regulation rather than de novo protein synthesis. Bioinformatics and data processing: The proteinScape 2.1 software (BrukerDaltonik GmbH) was used to submit MS/MS data to the following database: NCBI restricted to Drosophila (June 2011, 223,543 sequences) using the Mascot search engine (Mascot server v2.2, http://www.matrixscience.com). Parameters were set as follows: trypsin as enzyme with one allowed miscleavage, carbamidomethylation of cysteins as fixed modification and methionine oxidation as variable modifications. The mass tolerance for parent and fragment ions was set to 0.5 Da. Peptide identifications were accepted if the individual ion Mascot scores were above the identity threshold (the ion score is −10*log(P), where P is the probability that the observed match is a random event, P < 0.05). In case of ambiguous assignments (one compound fit to more than one peptide), peptide were accepted based on the peptide score, meaning that the peptide sequence with the highest score is accepted. The compilation of identified peptides to proteins was performed with the ProteinExtractor algorithm (Thiele et al., 2008, 2010), so that every protein reported was identified by at least one peptide with significant ion Mascot score (above the identity threshold).

INSTRUMENT(S): Bruker Daltonics HCT Series, HCTultra PTM

ORGANISM(S): Drosophila (fruit Flies)

SUBMITTER: E Com

LAB HEAD: E Com

PROVIDER: PXD000043 | Pride | 2013-03-04

REPOSITORIES: pride

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Proteomic profiling of thermal acclimation in Drosophila melanogaster.

Colinet Hervé H Overgaard Johannes J Com Emmanuelle E Sørensen Jesper Givskov JG

Insect biochemistry and molecular biology 20130213 4

Thermal acclimation drastically alters thermotolerance of ectotherms, but the mechanisms determining this plastic response are not fully understood. The present study investigates the proteomic response (2D-DIGE) of adult Drosophila melanogaster acclimated at 11, 25 or 31 °C. As expected 11 °C-acclimation improved cold tolerance and 31 °C-acclimation improved heat tolerance. We hypothesized that the marked organismal responses to acclimation could be detected at the proteomic level assuming that ...[more]

PMID: 23416132

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