Changes in the liver mitochondrial oxidation of succinate during cold-exposure.
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ABSTRACT:
SUBMITTER: Aithal HN
PROVIDER: S-EPMC1177068 | biostudies-other | 1971 Aug
REPOSITORIES: biostudies-other
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2011-10-01 | GSE31103 | GEO
Project description:We utilized a candidate gene approach using custom microarray constructed for our study species Drosophila montana and D. virilis to identify genes with modulated expression patterns under low temperature conditions. The flies were exposed to four different treatments (+5°C for 6 days, 0°C for 1 hour, two periods of recovery after cold stress and a control treatment). The aim of the study was to identify potential cold-responsive genes and to investigate differences in gene expression between the species. Microarray analysis revealed altogether 31 out of 219 genes on the array to show expression changes during different stages of cold stress. Among the potential stress tolerance genes detected earlier in D. melanogaster, hsr-omega was upregulated in both species during cold acclimation, expression changes in other genes being treatment- and species specific. Our microarray study clearly showed that different stages of cold response elicit changes at least in genes involved in heat shock response, circadian rhythm and metabolism. Cold- induced gene expression was investigated comparing four different treatments to the control treatment: 1) Cold acclimation: 14 days in control conditions, then 6 days at +5°C 2) Cold hardening: 20 days in control conditions, then1 hour at 0°C 3) 15-min recovery from chill coma: the 20-day-old flies were exposed to -6°C for 16 hours, after which they were let to recover for 15 minutes 4) 1-hour recovery from chill coma: the 20-day-old flies were exposed to -6°C for 16 hours, after which they were let to recover for 1 hour. In control treatment flies were kept for 20 days at 19°C. All the flies were 20-days old at the time of sample collection, and the light:dark cycle was 22 hours of light and 2 hours of dark. Because of the limited space on the array plate, the recovery samples were collected only for D. montana. All the samples were collected 5-6 hours after the lights had been turned on in the chamber and the flies were immediately immersed in liquid nitrogen, after which they were stored at -84ºC. Three pools of ten flies were collected from each treatment group.
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