Publications by authors named "Pablo Sambucetti"

Heat-induced hormesis in longevity is the increase in life span resulting from the previous exposure to a mild heat stress early in life. Here we examined heat-induced hormesis of Drosophila buzzatii in five mass-mating populations, which were derived from five wild populations along an elevation gradient from 202 to 1855 m above sea level in North-Western Argentina. Five day old flies were exposed to 37.

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In insects, mating ability at elevated temperature can be relevant for adaptation to heat-stressed environments and global warming. Here, we examined copulation latency (T1), copulation duration (T2), and mating frequency (T3, an index of mating success) in two related sets of recombinant inbred lines (RIL) in Drosophila melanogaster at both elevated (33 °C) and benign (25 °C) temperatures. One of these RIL sets (RIL-SH2) was shown to be consistently more resistant in both heat knockdown and heat-shock survival assays than its related set (RIL-D48) in previous studies.

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In insects, thermal adaptation works on the genetic variation for thermotolerance of not only larvae and adults but also of the immobile stages of the life cycle including eggs. In contrast to adults and larvae, the genetic basis for thermal adaptation in embryos (eggs) remains to be tested in the model insect Drosophila melanogaster. Quantitative-trait loci (QTL) for heat-stress resistance in embryos could largely differ from previously identified QTL for larvae and adults.

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Reproduction and related traits such as mating success are strongly affected by thermal stress. We tested direct and correlated responses to artificial selection in replicated lines of that were selected for mating success at high temperature. Knockdown resistance at high temperature (KRHT) and chill-coma recovery (CCR) were tested as correlated selection responses.

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Longevity is a highly malleable trait which is influenced by many genetic and environmental factors including nutrition. Mild stress of dietary restriction (DR) is often beneficial by extending longevity in many organisms. Here, DR-induced effects on longevity were tested for genetic variation in a set of recombinant inbred lines (RIL) in D.

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An extremely high (about 100 %) increase in longevity is reported for a subset of recombinant inbred lines (RILs) of Drosophila melanogaster subjected to a cyclic heat stress throughout the adult life. Previous work showed that both longevity and heat sensitivity highly differed among RILs. The novel heat stress treatment used in this study consisted of 5 min at 38 °C applicated approximately every 125 min throughout the adult life starting at the age of 2 days.

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Two sibling Drosophila species dramatically divergent in longevity, Drosophila buzzatii and D. koepferae, were examined for possible effects of both developmental culture medium and dietary composition (DC) on longevity. Longevity was greatly increased in the longer lived D.

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Survival of a potentially lethal high temperature stress is a genetically variable thermal adaptation trait in many organisms. Organisms cope with heat stress by basal or induced thermoresistance. Here, we tested quantitative trait loci (QTL) for heat stress survival (HSS) in Drosophila melanogaster, with and without a cyclic heat-hardening pre-treatment, for flies that were reared at low (LD) or high (HD) density.

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Longevity is a typical quantitative trait which is influenced by multiple genes. Here we explore the genetic variation in longevity of Drosophila melanogaster in both mildly heat-stressed and control flies. Quantitative trait loci (QTL) analysis for longevity was performed in a single-sex environment at 25°C with and without a mild heat-stress pre-treatment, using a previously reported set of recombinant inbred lines (RIL).

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Starvation resistance (SR) is an important trait for survival of insects in the wild. We used recombinant inbred lines (RIL) to search for quantitative trait loci (QTL) in crosses between intercontinental inbred lines that were originally selected for heat-knockdown resistance. SR was measured as the time of survival under repeated events of starvation.

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The thermotolerance effect of heat hardening (also called short-term acclimation), knockdown resistance to high temperature (KRHT) with and without heat hardening and chill-coma recovery (CCR) are important phenotypes of thermal adaptation in insects and other organisms. Drosophila melanogaster from Denmark and Australia were previously selected for low and high KRHT, respectively. These flies were crossed to construct recombinant inbred lines (RIL).

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Clinal analysis for fitness-related traits provides a well-known approach to investigate adaptive evolution. Several fitness-related traits (developmental time, thorax length, wing length and wing loading) were measured at two laboratory generations (G7 and G33) of D. buzzatii from an altitudinal gradient from northwestern Argentina, where significant thermal differences persist.

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