Search results for "Drosophila."

On the analysis of viability data: an example with Drosophila.

1990

Larval competition experiments involving two wild type and eight mutant strains of Drosophila melanogaster have been carried out following the substitution procedure proposed by Mather and Caligari (1981). Our main goal has been to compare the competitive abilities of two phenotypically indistinguishable strains (wild and Oregon-R) by means of their responses with eight different mutants. Prior to the analyses of viability data, we have studied the normalizing effect of several transformations in order to determine which was best suited for the analyses. The differences found among the five transformations tested and the untransformed data were not very great. The folded power transformatio…

Drosophila suzukii (Diptera: Drosophilidae): a decade of research towards a sustainable integrated pest management program

2021

Abstract Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) also known as spotted-wing drosophila (SWD), is a pest native to Southeast Asia. In the last few decades, the pest has expanded its range to affect all major European and American fruit production regions. SWD is a highly adaptive insect that is able to disperse, survive, and flourish under a range of environmental conditions. Infestation by SWD generates both direct and indirect economic impacts through yield losses, shorter shelf life of infested fruit, and increased production costs. Fresh markets, frozen berries, and fruit export programs have been impacted by the pest due to zero tolerance for fruit infestation. As SWD co…

The Dorsocross T-box transcription factors promote tissue morphogenesis in the Drosophila wing imaginal disc.

2012

The Drosophila wing imaginal disc is subdivided into notum, hinge and blade territories during the third larval instar by formation of several deep apical folds. The molecular mechanisms of these subdivisions and the subsequent initiation of morphogenic processes during metamorphosis are poorly understood. Here, we demonstrate that the Dorsocross (Doc) T-box genes promote the progression of epithelial folds that not only separate the hinge and blade regions of the wing disc but also contribute to metamorphic development by changing cell shapes and bending the wing disc. We found that Doc expression was restricted by two inhibitors, Vestigial and Homothorax, leading to two narrow Doc stripes…

A comparison of the transcriptome of Drosophila melanogaster in response to entomopathogenic fungus, ionizing radiation, starvation and cold shock

2015

Background The molecular mechanisms that determine the organism's response to a variety of doses and modalities of stress factors are not well understood. Results We studied effects of ionizing radiation (144, 360 and 864 Gy), entomopathogenic fungus (10 and 100 CFU), starvation (16 h), and cold shock (+4, 0 and -4°C) on an organism's viability indicators (survival and locomotor activity) and transcriptome changes in the Drosophila melanogaster model. All stress factors but cold shock resulted in a decrease of lifespan proportional to the dose of treatment. However, stress-factors affected locomotor activity without correlation with lifespan. Our data revealed both significant similarities …

Effect of conditioned media on three genotypes ofDrosophila melanogaster: Physical, chemical, and biological aspects

1986

The uric acid contents in larvae, pupae, and culture media were studied during larval and pupal development in three genotypes of Drosophila melanogaster reared in both crowded and noncrowded conditions. The uric acid content and the response of genotypes in media supplemented with 10 and 15 mg/ml of uric acid were correlated with the outcome obtained in conditioned media. In addition, the behavior of genotypes in conditioned media is explained in terms of the physicochemical properties of the conditioned media, which include uric acid content, the amount of food ingested, the degree of free water, the physical disturbance within the cultures, and the particular response of each genotype to…

Larval competition in Drosophila melanogaster: frequency-dependence of viability

1988

The application of the overfeeding technique (interruption of the competition during larval development) to the study of larval competition in two-strain cultures of Drosophila melanogaster demonstrates the following points: (1) viability is a function of competition time; (2) viability becomes more frequency-dependent as competition time increases; (3) the dynamics of the “inner” subpopulation (adults that have passed all their development in a crowded condition) and “outer” subpopulation (adults coming from larvae recovered by interruption of competition) vary with time as regards frequency-dependence; and (4) the wild type strain Oregon is the active agent in competition with the strain …

Intra- and intergenotypic larval competition in Drosophila melanogaster : effect of larval density and biotic residues

1987

Flies in the north: locomotor behavior and clock neuron organization of Drosophila montana.

2012

The circadian clock plays an important role in adaptation in time and space by synchronizing changes in physiological, developmental, and behavioral traits of organisms with daily and seasonal changes in their environment. We have studied some features of the circadian activity and clock organization in a northern Drosophila species, Drosophila montana, at both the phenotypic and the neuronal levels. In the first part of the study, we monitored the entrained and free-running locomotor activity rhythms of females in different light-dark and temperature regimes. These studies showed that D. montana flies completely lack the morning activity component typical to more southern Drosophila speci…

Photoactivation of Drosophila melanogaster cryptochrome through sequential conformational transitions

2019

Time-resolved x-ray scattering reveals light-induced signal transduction in insect cryptochromes.

Photosensitive Alternative Splicing of the Circadian Clock Gene timeless Is Population Specific in a Cold-Adapted Fly, Drosophila montana.

2018

To function properly, organisms must adjust their physiology, behavior and metabolism in response to a suite of varying environmental conditions. One of the central regulators of these changes is organisms' internal circadian clock, and recent evidence has suggested that the clock genes are also important in the regulation of seasonal adjustments. In particular, thermosensitive splicing of the core clock gene <i>timeless</i> in a cosmopolitan fly, <i>Drosophila melanogaster</i> , has implicated this gene to be involved in thermal adaptation. To further investigate this link we examined the splicing of <i>timeless</i> in a northern malt fly species, <i&…