Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085593 (chills)
 4,268 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The medfly Ceratitis capitata is an agricultural pest distributed worldwide thanks, in part, to its phenotypic plasticity of thermal tolerance. Cold exposure has been shown to reduce C. capitata survival, which may affect its distribution in areas with subfreezing temperatures. When insects are increasingly cooled, they attain a critical thermal threshold and enter a chill-coma state characterized by cessation of movement. It is not clear how a rapid cold exposure affects the physiological state of medflies, and how this is influenced by age and population heterogeneity. In order to approach these questions, C. capitata single-sex laboratory populations of 15 and 30 days old were subjected to a chill-coma recovery assay, and separated according to their recovery time in three subgroups: Fast-Subgroups, Intermediate-Subgroups, and Slow-Subgroups. Thereafter, we analyzed their survival, behavioral, and gene expression outputs. In female and old male populations, we found that flies with the slowest recovery time had a reduced life expectancy, a higher initial mortality rate, and a worse climbing performance compared with flies that recovered faster. Therefore, we were able to separate subgroups that developed chilling-injury from subgroups that had a reversible full recovery after cold exposure. The gene expression analysis of the heat shock protein genes hsp70 and hsp83 showed no clear association with the parameters studied. Interestingly, thorax expression levels of the Cu/Zn superoxide dismutase gene were elevated during the recovery phase in the Fast-Subgroups, but remained constant in the Slow-Subgroups that developed chilling-injury. On the other hand, none of the young male subgroups seemed to have suffered irreversible damage. Thus, we concluded that depending on age and population heterogeneity, chill-coma recovery time points out significant differences on individual cold tolerance. Moreover, the inability to properly induce the antioxidant defense system to counteract the oxidative damage caused by cold seems to contribute to the development of chilling-injury.
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PMID:Analysis of survival, gene expression and behavior following chill-coma in the medfly Ceratitis capitata: effects of population heterogeneity and age. 2544 2

The remodeling of membrane composition by changes in phospholipid head groups and fatty acids (FA) degree of unsaturation has been associated with the maintenance of membrane homeostasis under stress conditions. Overall lipid levels and the composition of cuticle lipids also influence insect stress resistance and tissue protection. In a previous study, we demonstrated differences in survival, behavior and Cu/Zn superoxide dismutase gene expression between subgroups of Ceratitis capitata flies that had a reversible recovery from chill-coma and those that developed chilling-injury. Here, we analyzed lipid profiles from comparable subgroups of 15 and 30-day-old flies separated according to their recovery time after a chill-coma treatment. Neutral and polar lipid classes of chill-coma subgroups were separated by thin layer chromatography and quantified by densitometry. FA composition of polar lipids of chill-coma subgroups and non-stressed flies was evaluated using gas chromatography coupled to mass spectrometry. Higher amounts of neutral lipids such as triglycerides, diacylglycerol, wax esters, sterol esters and free esters were found in male flies that recovered faster from chill-coma compared to slower flies. A multivariate analysis revealed changes in patterns of storage and cuticle lipids among subgroups both in males and females. FA unsaturation increased after cold exposure, and was higher in thorax of slower subgroups compared to faster subgroups. The changes in neutral lipid patterns and FA composition depended on recovery time, sex, age and body-part, and were not specifically associated with the development of chilling-injury. An analysis of phospholipid classes showed that the phosphatidylcholine to lysophosphatidylcholine ratio (PC/LPC) was significantly higher, or showed a tendency, in subgroups that may have developed chilling-injury compared to those with a reversible recovery from coma.
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PMID:Chill-coma recovery time, age and sex determine lipid profiles in Ceratitis capitata tissues. 2686 23