Ethanol Sensitivity and Tolerance in Long-Term Memory Mutants of Drosophila melanogaster

Ethanol Sensitivity and Tolerance in Long-Term Memory Mutants of Drosophila melanogaster - Berger - 2008 - Alcoholism: Clinical and Experimental Research - Wiley Online Library Mutants of the learning and/or memory pathways have differential responses to ethanol tolerance. Some mutants increased amnesia/learning loss, while others had an opposite effect to ethanol tolerance. Researchers tested a collection of 60 long-term memory mutants for 52 loci where these mutants limit learning so normal function of each mutation are thought to play into the long-term memory pathway. Researchers then ran an ethanol assay and quantified the ethanol tolerance of each mutant. The data suggests that these pathways overlap and suggest specific genes for each pathway. 

Altered regulation of sleep and feeding contributes to starvation resistance in Drosophila melanogaster

By generating starvation- resistant flies through experimental evolution, these researchers at UNLV were able to more closely observe the relationships between sleep behavior, feeding, foraging, and starvation resistance. Because sleep and feeding are related to metabolic rates, they could potentially contribute to Drosophila melanogaster resistance under starvation conditions.  The flies used in this experiment have been bred over 60 generations in order to become starvation resistant. These flies were bred on an agar diet that was devoid of calories, and live around 18 days when under starvation conditions. Flies that have not been selected for starvation resistance survive around 2-3 days.

Dopamine modulates acute response to cocaine, nicotine and ethanol in Drosophila

Dopamine modulates acute responses to cocaine, nicotine and ethanol in Drosophila In this paper researchers study the role of dopamine in different drug exposures. To test how flies responded to cocaine and nicotine they tested how quickly they could climb up a glass tube. With the effects of the drug, flies would remain at the bottom of the tube. Cocaine recovery time was fifteen minutes for moderate doses and nicotine was five minutes for moderate doses. To test the effects of Dopamine, researchers used Dopamine depleted flies by feeding them a competitive antagonist to tyrosine hydroxylase which in necessary for dopamine synthesis. A complete lack of Dopamine results in lethality, so flies tested only have significantly reduced dopamine in their systems. When these flies were tested with cocaine or nicotine they shows a 35% reduction in ability to geotax (climb). These factors are contributed to dopamine reductions, due to a normalized response when the dopamine reduction was rev ...

Octopamine controls starvation resistance, life span and metabolic traits in Drosophil

Survival of organisms depends partially on their response to stress. For Humans and other organisms, these responses are regulated, it part, by epinephrine and norepinephrine. This system in humans contains many feedback loops and is complicated to study. Invertebrate systems are easier to study. This research focuses on how similar chemicals in Drosophila have an effect certain characteristics. Specifically their research found that chemicals had an effect on lifespan, starvation resistance, and body fat in fruit flies, as well as other minor traits.

The Effects of Ethanol on Courtship and Mating Preference in Drosophila melanogaster

In this paper the author tested the effect of ethanol consumption on Drosphila's courtship patterns and fecundity rate. Virgin males are separated into two groups; one getting food with water and one made with ethanol. Food consumption was highly regulated for 4 days. After four days males were combined with virgin females. They observed a significantly shorter courtship period, but a significant higher fecundity rates for flies with ethanol exposures. Flies also prefered ethanol food significantly to water food. 

Repeated stress exposure results in a survival-reproduction trade off in Drosophila Melanogaster.

Repeated stress exposure results in a survival–reproduction trade-off in Drosophila melanogaster | Proceedings of the Royal Society of London B: Biological Sciences Researchers took 35 isogenic female lines from London, Ontario, Canada where the multiple cold cycles occur. They grew flies up from these different lines and sorted them via CO2 anesthetics, with 15 Virgin females per vial and 30 virgin males per vial. Both male and female vials were stored at 22 degrees Celsius. Females, after waiting 3 days to eliminate possibility of CO2 effects the flies, the flies where placed into one of four groups in order to control for varying conditions. One group contained flies only exposed to 22 degrees C. One was exposed to -.5 degrees C for 10 hrs. Another was a multiple cold exposure, where flies were either exposed to 2, 3, 4, or 5 two hour periods of -.5 degrees C, with 22 hrs in between exposure times and ending at 7 days old to account for age influences. The last group was a single ...

January 23, 2017 Zhan, Y. P.. Liu, L.. Zhu, Y.. Taotie neurons regulate appetite in Drosophila. Nature 7, Article number: 13633(2016). Doi: 10.1038/ncomms13633

New findings regarding the neurological regulation of feeding rate suggest interesting factors behind fruit fly nutrition and obesity. After a screening of GAL4 lines in adult Drosophila brains, one line (Taotie-GAL4) was identified to have an impact on food intake. Further study showed that activation of Taotie neurons increased food intake over five-fold when compared to control flies. However, when starved for over 60 hours, Taotie activated flies showed no difference in food intake compared to equally starved non-activated flies. This suggests that activation of the Taotie neuron is involved in hunger response normally. Activation of the Taotie neuron in flies that were sufficiently nourished resulted in fly obesity. Interestingly, inactivation of activated neurons effectively reversed the obese trend, as deactivated flies not only returned to normal feeding habits, but effectively controlled their food intake until normalcy was established. 

Role of the metF and metJ genes on the vitamin B12 regulation of methionine gene expression: Involvement of N5-methyltetrahydrofolic acid

This article examines the process of metE repression in E coli strains. MetE is repressed with the assistance of many other molecules within the methionine pathways, it has also previously been known to be repressed by presence methionine in the growth medium. Studies also have shown that when E coli strains are grown in the presence of B12 vitamin, metE is significantly repressed. The exact pathway of repression of metE through vitamin B12 has not been concluded. This study aimed to determine the role of metF in B12 repression, and MetJ in the repression of metF and metE through B12.