Drosophila Melanogaster as a Model Organism :)

Hi everyone! :)

Today, I'm gonna share a post about Drosophila Melanogaster and three different experiments in which Drosophila was used as a model organism.

This text is also one of my lab reports for BIO 106 and to be honest, I wrote it at only one night. Because of that, there can be some grammatical problems :D However, I hope, you will enjoy that and learn new things from the text :)

DROSOPHILA MELANOGASTER

According to the evolution theory, it is thought that all living cells have a common ancestor cell and during the evolution of all living things, most of the basic properties of this ancestor cell have been conserved. That means, all species have mostly similar genetic properties and the differences between them are the results of small changes in their genome. As a result of that, especially in experimental biology researches, different species can be used as a test subject instead of each other. However, a certain number of organisms and cells which have different advantages about different experimental properties such as rapid reproducing, simplicity and transparency, are widely used as biological models in different experiments. In addition to that, because these chosen and determined species are used commonly by different scientists for different experiments, they can be examined deeply and scientific knowledge about the genetic properties of these species is very detailed. As a result of their different benefits, these species such as Escherichia coli and Saccharomyces cerevisiae are used as model organisms in biological experiments especially which are about human biology.

Drosophila Melanogaster is also one of these model organisms which are commonly used in experiments about human diseases and development stages. The usage of Drosophila in biological experiments have different advantages and disadvantages depending on the expectations from the experiments.

The most important benefit of Drosophila is that its genome was completely sequenced and published, and it contains a lot of conserved gene sequences which are similar with human genes. In addition to that, 75% of the genes which are related to different kinds of human diseases also can be find in its genome, too. As a result, Drosophila is commonly used as a model organism in drug design experiments for different human diseases.

The rapid life cycle of Drosophila is also an advantage of this model organism. Because from a single pair of this organism, it can be obtained more than a hundred of offspring which has identical genetic properties in about 10 days under laboratory conditions. In addition, to breed this organism under laboratory conditions is completely easier comparing to other species. They don’t need to have a complex diet to grow and they are not so expensive to study.

To have changing developmental stages such as embryo, larva, pupa and adult is a benefit of using Drosophila in different experiments. Because each stage of its development can be used for different researches such as about neuronal development and morphological changes. In addition to that, the adult stage of Drosophila has a complex systematic structure which has similar properties with human body systems and this property makes them also very useful for experiments about human development.

On the other side, Drosophila melanogaster has polytene chromosomal structure: its chromosomes are very big and they have light and dark colors of lines on them. As a result, its chromosomes can be observed under light microscope easily. And its body structures can be also observed with and without light microscope easily in different researches.

In addition to its advantages, Drosophila has some disadvantages for some biological experiments. One of its disadvantages is that even though they have similarities, the anatomy of Drosophila is actually very different. In addition to that, the fruit fly doesn’t have a complete adaptive immune system and they are not very useful for these type of experiments. And, Drosophila also doesn’t have some neurotransmitters and receptors which are important for neurological human diseases and this can be a disadvantage of using Drosophila instead of other species.

However, even though Drosophila Melanogaster has some disadvantages, its benefits are completely higher and it is commonly used in different kind of experiments about human diseases. One of these experiments, in which Drosophila was used is about the malignancy cancer investigations and different therapies for it. Even though some anatomical and physiological properties of Drosophila are quite different from humans, malignant tumors have a lot of similar effects on humans and Drosophila. The cells in both species firstly have changes in their developmental progress and their growth isn’t under control anymore. At the end, the tumor cells become immortal and cause the death of the patient. As a result of these similarities in stages of malignancy cancer in both species, different treatment options were tried on the Drosophila to be used in humans and by using these similarities and widely studied genomic properties of Drosophila, it was tried to understand the different molecular bases of malignancy.

Another experiment which was performed by using Drosophila Melanogaster is mapping the human cancer pathways. The human cancers develop through different stages such as mutations in cell – cycle, cell – death pathway and interactions about tumors, and to observe these steps of tumor formation easily, a model organism which has simple properties such as Drosophila was used. According to the results of some other experiments, by using the high ability in Drosophila to study interactions of tumor suppressors and oncogenes and, to generate tumor development and metastasis models; the hallmarks of cancer in Drosophila was determined, the pathways which promote the self – sufficiency was studied by using information about the effects of genes in Drosophila to self – sufficiency in growing and proliferation processes. And then, by using the different and well-studied cell signaling pathways of Drosophila, the effects of restraints against different processes such as cell proliferation, cell growth or the effects of blocking them was observed and the important cancer pathways such as Ras^ACT and Nothch^ACT were examined.

Drosophila Melanogaster is an appropriate model organism for modelling the neurodegenerative diseases and Parkinson’s disease is also one of the neurodegenerative diseases which were modelled by using Drosophila in an other experiment. The Parkinson’s disease is a disorder about movement and it is the result of losing the dopaminergic neurons in the substantia nigra part of the brain and also the result of filamentous intraneuronal inclusions formation. The gene α – synuclein is related to this disease and it is also effective on accumulation in Lewy bodies which are the filamentous intraneuronal inclusions. In order to express a genetic approach for Parkinson’s disease by using Drosophila, in this experiment firstly, the normal and mutant α – synuclein genes of Drosophila were expressed. After that, the loss of dopaminergic neurons in adulthood and Lewy bodies which contain α – synuclein were produced. In addition to that, a locomotor dysfunction was also generated in Drosophila and the results were observed and then used for modelling the disease by using the effects on Drosophila Melanogaster.

See you in another post! :)

LOVE YOU <3

Kumsal