scholarly journals Drosophila melanogaster Is a Genetically Tractable Model Host for Mycobacterium marinum

2003 ◽  
Vol 71 (6) ◽  
pp. 3540-3550 ◽  
Author(s):  
Marc S. Dionne ◽  
Nafisa Ghori ◽  
David S. Schneider

ABSTRACT Mycobacterium marinum is a pathogenic mycobacterial species that is closely related to Mycobacterium tuberculosis and causes tuberculosis-like disease in fish and frogs. We infected the fruit fly Drosophila melanogaster with M. marinum. This bacterium caused a lethal infection in the fly, with a 50% lethal dose (LD50) of 5 CFU. Death was accompanied by widespread tissue damage. M. marinum initially proliferated inside the phagocytes of the fly; later in infection, bacteria were found both inside and outside host cells. Intracellular M. marinum blocked vacuolar acidification and failed to colocalize with dead Escherichia coli, similar to infections of mouse macrophages. M. marinum lacking the mag24 gene were less virulent, as determined both by LD50 and by death kinetics. Finally, in contrast to all other bacteria examined, mycobacteria failed to elicit the production of antimicrobial peptides in Drosophila. We believe that this system should be a useful genetically tractable model for mycobacterial infection.

Author(s):  
Great David Bagu ◽  
Simeon Omale ◽  
Walter Mdekera Iorjiim ◽  
Mary O. Uguru ◽  
Steven Samuel Gyang

Aim: The study aimed at assessing the LD50, fecundity and locomotor effects of Ximenia americana L in Drosophila melanogaster. Study Design: The study was an experimental design. Place and Duration of Study: The study was done in the drosophila laboratory, Africa Centre of Excellence in Phytomedicine Research and Development (ACEPRD), University of Jos, Nigeria between November 2019 and Match, 2020. Methods: The experimental animals (1-3 days old) of both sexes were exposed to different concentrations (1 mg 10 mg 50 mg, 100 mg, 200 mg, 250 mg 300 mg, 350 mg, 400 mg, 450 mg) of the plant extract per oral for seven days to determine the lethal dose, LD50. Thereafter, five days treatment was done using 50 mg, 100 mg 200 mg and 300 mg concentrations of the extract to assay for fecundity and locomotor effect in the fruit fly. Results: The LD50 of the methanol extract of Ximenia americana in D. melanogaster was found to be 327.7 mg, this showed that the plant extract is relatively safe. Also, the result showed that both fecundity and locomotor behaviour of the treated and untreated flies was not significantly (P > 0.05) different. Thus, the extract at the used concentrations does not affects significantly both the reproductive capacity and the motor functions in the fruit fly. Conclusion: All the tested concentrations used in this research are relatively safe (because of high LD50 327.7 mg) in the fruit fly and slightly increase the emergence of new fly with no noticeable negative effect in locomotor activity.


1987 ◽  
Vol 21 (3) ◽  
pp. 226-232 ◽  
Author(s):  
C. J. Trahan ◽  
E. H. Stephenson ◽  
J. W. Ezzell ◽  
W. C. Mitchell

To evaluate the efficacy of a commercial bacterial vaccine in protecting Strain 13 guineapigs against fatal Bordetella bronchiseptica pneumonia, it was necessary to establish the infectivity and disease pathogenesis induced by virulent organisms. When guineapigs were exposed to small-particle aerosols of varying concentrations of virulent B. bronchiseptica, a spectrum of disease was produced that ranged from inapparent illness to fulminant bronchopneumonia. Clinical signs began by day 4 after exposure, and were evidenced by anorexia, weight loss, respiratory distress and serous to purulent nasal discharge. Pathological alterations were limited to the respiratory system. Moribund animals exhibited a suppurative necrotizing bronchopneumonia and necrotizing tracheitis. In animals that survived the challenge, the bacteria were eliminated from the lungs by day 28 but continued to persist in the laryngeal area and the trachea. The median infectious dose and the median lethal dose were estimated to be 4 colony-forming units (CFU) and 1314 CFU respectively. These data suggest that the guineapig will be a valuable model system in which to study interactions between Bordetella species and host cells as well as to evaluate potential B. bronchiseptica immunogens.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Rachel Paul ◽  
Guillaume Giraud ◽  
Katrin Domsch ◽  
Marilyne Duffraisse ◽  
Frédéric Marmigère ◽  
...  

AbstractFlying insects have invaded all the aerial space on Earth and this astonishing radiation could not have been possible without a remarkable morphological diversification of their flight appendages. Here, we show that characteristic spatial expression profiles and levels of the Hox genes Antennapedia (Antp) and Ultrabithorax (Ubx) underlie the formation of two different flight organs in the fruit fly Drosophila melanogaster. We further demonstrate that flight appendage morphology is dependent on specific Hox doses. Interestingly, we find that wing morphology from evolutionary distant four-winged insect species is also associated with a differential expression of Antp and Ubx. We propose that variation in the spatial expression profile and dosage of Hox proteins is a major determinant of flight appendage diversification in Drosophila and possibly in other insect species during evolution.


2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Xiaochan Xu ◽  
Wei Yang ◽  
Binghui Tian ◽  
Xiuwen Sui ◽  
Weilai Chi ◽  
...  

AbstractThe fruit fly, Drosophila melanogaster, has been used as a model organism for the molecular and genetic dissection of sleeping behaviors. However, most previous studies were based on qualitative or semi-quantitative characterizations. Here we quantified sleep in flies. We set up an assay to continuously track the activity of flies using infrared camera, which monitored the movement of tens of flies simultaneously with high spatial and temporal resolution. We obtained accurate statistics regarding the rest and sleep patterns of single flies. Analysis of our data has revealed a general pattern of rest and sleep: the rest statistics obeyed a power law distribution and the sleep statistics obeyed an exponential distribution. Thus, a resting fly would start to move again with a probability that decreased with the time it has rested, whereas a sleeping fly would wake up with a probability independent of how long it had slept. Resting transits to sleeping at time scales of minutes. Our method allows quantitative investigations of resting and sleeping behaviors and our results provide insights for mechanisms of falling into and waking up from sleep.


1999 ◽  
Vol 19 (2) ◽  
pp. 1159-1170 ◽  
Author(s):  
Madeline A. Crosby ◽  
Chaya Miller ◽  
, Tamar Alon ◽  
Kellie L. Watson ◽  
C. Peter Verrijzer ◽  
...  

ABSTRACT The genes of the trithorax group (trxG) inDrosophila melanogaster are required to maintain the pattern of homeotic gene expression that is established early in embryogenesis by the transient expression of the segmentation genes. The precise role of each of the diverse trxG members and the functional relationships among them are not well understood. Here, we report on the isolation of the trxG gene moira(mor) and its molecular characterization. morencodes a fruit fly homolog of the human and yeast chromatin-remodeling factors BAF170, BAF155, and SWI3. mor is widely expressed throughout development, and its 170-kDa protein product is present in many embryonic tissues. In vitro, MOR can bind to itself and it interacts with Brahma (BRM), an SWI2-SNF2 homolog, with which it is associated in embryonic nuclear extracts. The leucine zipper motif of MOR is likely to participate in self-oligomerization; the equally conserved SANT domain, for which no function is known, may be required for optimal binding to BRM. MOR thus joins BRM and Snf5-related 1 (SNR1), two known Drosophila SWI-SNF subunits that act as positive regulators of the homeotic genes. These observations provide a molecular explanation for the phenotypic and genetic relationships among several of the trxG genes by suggesting that they encode evolutionarily conserved components of a chromatin-remodeling complex.


2005 ◽  
Vol 83 (2) ◽  
pp. 368-371 ◽  
Author(s):  
Mark J Fitzpatrick ◽  
Evelyn Szewczyk

Denticles are small projections on the underside of larval fruit flies that are used to grip the substrate while crawling. Previous studies have shown that (i) there is natural variation in denticle number and pattern between Drosophila melanogaster (Meigen, 1830) and several closely related species and (ii) mutations affecting denticle morphology have negative effects on locomotory performance. We hypothesized that there would be a correlation between denticle number and locomotory performance within populations of D. melanogaster. Despite finding considerable variation in denticle number, we found no correlation between denticle number and three measurements of larval locomotion: speed, acceleration, and absolute turning rate.


2010 ◽  
Vol 72 (4) ◽  
pp. 231-234 ◽  
Author(s):  
James Billingsley ◽  
Kimberly A. Carlson

Do our genes exclusively control us, or are other factors at play? Epigenetics can provide a means for students to use inquiry-based methods to understand a complex biological concept. Students research and design an experiment testing whether dietary supplements affect the lifespan of Drosophila melanogaster over multiple generations.


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