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.
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.
Qingying Menga, Yumei Zhuanga, Zhe Yinga, Rahul Agrawala, Xia Yanga, , , Fernando Gomez-Pinillaa,b, ,
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 ...
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.
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 | 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 ...
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.
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.