scholarly journals Sterols as dietary markers for Drosophila melanogaster

2019 ◽  
Author(s):  
Oskar Knittelfelder ◽  
Elodie Prince ◽  
Susanne Sales ◽  
Eric Fritzsche ◽  
Thomas Wöhner ◽  
...  
Keyword(s):  
Drosophila Melanogaster ◽  
Cold Acclimation ◽  
Lipid Membranes ◽  
Population Based ◽  
Sterol Composition ◽  
Molar Ratio ◽  
Shotgun Lipidomics ◽  
Organ Specific ◽  
In The Wild ◽  
Lipidome Analysis

AbstractDuring cold acclimation fruit flies switch their feeding from yeast to plant food, however there are no robust markers to monitor it in the wild. Drosophila melanogaster is a sterol auxotroph and relies on dietary sterols to produce lipid membranes, lipoproteins and molting hormones. We employed shotgun lipidomics to quantify eight major food sterols in total extracts of heads, female and male genital tracts of adult flies. We found that their sterol composition is dynamic and reflective of flies diet in an organ-specific manner. Season-dependent changes observed in the organs of wild-living flies suggested that the molar ratio between yeast (ergosterol, zymosterol) and plant (sitosterol, stigmasterol) sterols is a quantifiable, generic and unequivocal marker of their feeding behavior, including cold acclimation. It provides technically simpler and more contrast readout compared to the full lipidome analysis and is suitable for ecological and environmental population-based studies.

scholarly journals Repeated stress exposure results in a survival–reproduction trade-off in Drosophila melanogaster

2009 ◽  
Vol 277 (1683) ◽  
pp. 963-969 ◽  
Author(s):  
Katie E. Marshall ◽  
Brent J. Sinclair
Keyword(s):  
Drosophila Melanogaster ◽  
Model Organism ◽  
Intrinsic Rate ◽  
Intrinsic Rate Of Increase ◽  
Stress Exposure ◽  
Trade Off ◽  
Repeated Stress ◽  
Rate Of Increase ◽  
In The Wild ◽  
Future Reproduction

While insect cold tolerance has been well studied, the vast majority of work has focused on the effects of a single cold exposure. However, many abiotic environmental stresses, including temperature, fluctuate within an organism's lifespan. Given that organisms may trade-off survival at the cost of future reproduction, we investigated the effects of multiple cold exposures on survival and fertility in the model organism Drosophila melanogaster . We found that multiple cold exposures significantly decreased mortality compared with the same length of exposure in a single sustained bout, but significantly decreased fecundity (as measured by r , the intrinsic rate of increase) as well, owing to a shift in sex ratio. This change was reflected in a long-term decrease in glycogen stores in multiply exposed flies, while a brief effect on triglyceride stores was observed, suggesting flies are reallocating energy stores. Given that many environments are not static, this trade-off indicates that investigating the effects of repeated stress exposure is important for understanding and predicting physiological responses in the wild.

scholarly journals REPRODUCTION IN CAGE POPULATIONS OF A POLYMORPHISM REGULARLY OBSERVED IN THE NATURAL POPULATIONS OF DROSOPHILA MELANOGASTER IN FRANCE

Genetics ◽  
1978 ◽  
Vol 88 (4) ◽  
pp. 755-759
Author(s):  
Annie Fleuriet
Keyword(s):  
Drosophila Melanogaster ◽  
Natural Populations ◽  
Rate Of Return ◽  
Rapid Rate ◽  
Experimental Conditions ◽  
Co2 Sensitivity ◽  
In The Wild ◽  
Strong Forces

ABSTRACT Polymorphism for both alleles of a gene ref(2)P, which is a usual trait of French natural populations of Drosophila melanogaster, can be reproduced in experimental conditions. ref(2)P is a gene for resistance to the hereditary, noncontagious Rhabdovirus α, responsible for CO2 sensitivity in Drosophila melanogaster. The equilibrium frequencies observed in cages are the same as in the wild, whether α virus is present or not. The rapid rate of return to these equilibrium frequencies indicates that strong forces, which remain to be determined, are responsible for the maintenance of this polymorphism.

The development of the sensory neuron pattern in the antennal disc of wild-type and mutant (lz3, ssa) Drosophila melanogaster

Development ◽  
1991 ◽  
Vol 112 (4) ◽  
pp. 1063-1075
Author(s):  
M.C. Lienhard ◽  
R.F. Stocker
Keyword(s):  
Drosophila Melanogaster ◽  
Sensory Neuron ◽  
Antennal Segment ◽  
Wild Type ◽  
Homeotic Mutant ◽  
In The Wild ◽  
The Brain ◽  
Antennal Disc ◽  
Antennal Nerve

The development of the sensory neuron pattern in the antennal disc of Drosophila melanogaster was studied with a neuron-specific monoclonal antibody (22C10). In the wild type, the earliest neurons become visible 3 h after pupariation, much later than in other imaginal discs. They lie in the center of the disc and correspond to the neurons of the adult aristal sensillum. Their axons join the larval antennal nerve and seem to establish the first connection towards the brain. Later on, three clusters of neurons appear in the periphery of the disc. Two of them most likely give rise to the Johnston's organ in the second antennal segment. Neurons of the olfactory third antennal segment are formed only after eversion of the antennal disc (clusters t1-t3). The adult pattern of antennal neurons is established at about 27% of metamorphosis. In the mutant lozenge3 (lz3), which lacks basiconic antennal sensilla, cluster t3 fails to develop. This indicates that, in the wild type, a homogeneous group of basiconic sensilla is formed by cluster t3. The possible role of the lozenge gene in sensillar determination is discussed. The homeotic mutant spineless-aristapedia (ssa) transforms the arista into a leg-like tarsus. Unlike leg discs, neurons are missing in the larval antennal disc of ssa. However, the first neurons differentiate earlier than in normal antennal discs. Despite these changes, the pattern of afferents in the ectopic tarsus appears leg specific, whereas in the non-transformed antennal segments a normal antennal pattern is formed. This suggests that neither larval leg neurons nor early aristal neurons are essential for the outgrowth of subsequent afferents.

scholarly journals Costs of cold acclimation on survival and reproductive behavior in Drosophila melanogaster

PLoS ONE ◽  
2018 ◽  
Vol 13 (5) ◽  
pp. e0197822 ◽  
Author(s):  
Elizabeth R. Everman ◽  
Jennifer L. Delzeit ◽  
F. Kate Hunter ◽  
Jennifer M. Gleason ◽  
Theodore J. Morgan
Keyword(s):  
Drosophila Melanogaster ◽  
Cold Acclimation ◽  
Reproductive Behavior

Markedly Reduced Risk of Internal Malignancies in Patients With Vitiligo: A Nationwide Population-Based Cohort Study

2019 ◽  
Vol 37 (11) ◽  
pp. 903-911 ◽  
Author(s):  
Jung Min Bae ◽  
Kee Yang Chung ◽  
Sook Jung Yun ◽  
Heesu Kim ◽  
Byung Cheol Park ◽  
...  
Keyword(s):  
Cohort Study ◽  
Immune Surveillance ◽  
Population Based ◽  
Incidence Rates ◽  
Control Group ◽  
Frequency Matching ◽  
Organ Specific ◽  
Using Data ◽  
Risk Of Cancer ◽  
Reduced Risk

PURPOSE Recent studies indicated that the autoimmunity of vitiligo exerts effects on cells other than melanocytes, which confer reduced risks of both melanoma and nonmelanoma skin cancers in patients with vitiligo. However, the risk of internal malignancy in patients with vitiligo has not been elucidated. PATIENTS AND METHODS We conducted a population-based retrospective cohort study using data from the Korean National Health Insurance claims database obtained from January 2007 to December 2016. All patients age 20 years or older with vitiligo who had at least two contacts with a physician from 2009 to 2016, during which a principal diagnosis was made, were identified (vitiligo group). Controls were randomly selected (two per patient with vitiligo) after frequency matching with the vitiligo group for age and sex during the same period (control group). RESULTS A total of 101,078 patients with vitiligo and 202,156 controls without vitiligo were included. The incidence rates of internal malignancies were 612.9 and 708.9 per 100,000 person-years in the vitiligo and control groups, respectively. Patients with vitiligo showed a significantly reduced risk of overall internal malignancies (hazard ratio [HR], 0.86; 95% CI, 0.82 to 0.89; P < .001) compared with controls without vitiligo after adjustments for age, sex, and comorbidities. With regard to organ-specific malignancies, patients with vitiligo showed a remarkably decreased risk of cancer in the colon and rectum (HR, 0.62; 95% CI, 0.55 to 0.69; P < .001), ovary (HR, 0.62; 95% CI, 0.46 to 0.83; P < .001), and lung (HR, 0.75; 95% CI, 0.65 to 0.86; P < .001). CONCLUSION Vitiligo was associated with a reduced risk of overall internal malignancies. These findings suggest that autoimmune diseases, including vitiligo, may provide immune surveillance for the development of cancer beyond the targeted organ.

scholarly journals The Formation and Properties of Thin Lipid Membranes from HK and LK Sheep Red Cell Lipids

1967 ◽  
Vol 50 (6) ◽  
pp. 1729-1749 ◽  
Author(s):  
Thomas E. Andreoli ◽  
J. Andrew Bangham ◽  
Daniel C. Tosteson
Keyword(s):  
Lipid Membranes ◽  
Transference Number ◽  
Cholesterol Content ◽  
Membrane Voltage ◽  
Transference Numbers ◽  
Molar Ratio ◽  
Membrane Thickness ◽  
High Potassium ◽  
Cation Selectivity ◽  
High Degree

Lipids were obtained from high potassium (HK) and low potassium (LK) sheep red cells by sequential extraction of the erythrocytes with isopropanol-chloroform, chloroform-methanol-0.1 M KCl, and chloroform. The extract contained cholesterol and phospholipid in a molar ratio of 0.8:1.0, and less than 1% protein contaminant. Stable thin lipid membranes separating two aqueous compartments were formed from an erythrocyte lipid-hydrocarbon solution, and had an electrical resistance of ∼108 ohm-cm2 and a capacitance of 0.38–0.4 µf/cm2. From the capacitance values, membrane thickness was estimated to be 46–132 A, depending on the assumed value for the dielectric constant (2.0–4.5). Membrane voltage was recorded in the presence of ionic (NaCl and/or KCl) concentration gradients in the solutions bathing the membrane. The permeability of the membrane to Na+, K+, and Cl- (expressed as the transference number, Tion) was computed from the steady-state membrane voltage and the activity ratio of the ions in the compartments bathing the membrane. TNa and TK were approximately equal (∼0.8) and considerably greater than TCl (∼0.2). The ionic transference numbers were independent of temperature, the hydrocarbon solvent, the osmolarity of the solutions bathing the membranes, and the cholesterol content of the membranes, over the range 21–38°C. The high degree of membrane cation selectivity was tentatively attributed to the negatively charged phospholipids (phosphatidylethanolamine and phosphatidylserine) present in the lipid extract.

scholarly journals Arabian oryx reintroduction in Oman: successes and setbacks

Oryx ◽  
1999 ◽  
Vol 33 (2) ◽  
pp. 168-175 ◽  
Author(s):  
J. A. Spalton ◽  
M. W. Lawerence ◽  
S. A. Brend
Keyword(s):  
Wild Population ◽  
Species Conservation ◽  
Population Based ◽  
Monitoring Programme ◽  
New Approach ◽  
The World ◽  
In The Wild ◽  
Arabian Oryx ◽  
Supplementary Feed

AbstractThe return of the Arabian oryx Oryx leucoryx to Oman symbolized the success of a new approach to species conservation and established reintroduction as a conservation tool. Ten years after the species had been exterminated in the wild by poaching, the first 10 founder oryx, descendants of the ′World Herd′, were reintroduced to the desert in central Oman in January 1982. A second release followed in 1984 and the population grew slowly through a 3-year drought that was broken by rain in June 1986. Further years of good rainfall and more founders meant that by April 1990 there were over 100 oryx in the wild, independent of supplementary feed and water, and using a range of over 11,000 sq km. At that time a new monitoring programme was implemented that allowed the transition from individual- to population-based monitoring and management. The population continued to grow and by October 1995 numbered approximately 280 in the wild (of which 22 were surviving founders) and used over 16,000 sq km of the Arabian Oryx Sanctuary. However, in February 1996 poaching resumed and oryx were captured for sale as live animals outside the country. Despite the poaching the population continued to increase and by October 1996 was estimated to be just over 400. However, poaching intensified and continued through late 1996 and 1997. By September 1998 it had reduced the wild population to an estimated 138 animals, of which just 28 were females. The wild population was no longer considered viable and action was taken to rescue some of the remaining animals from the wild to form a captive herd.

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