Model Organisms

Zantiks units measure the behaviour of a range of model organisms. These include larval and adult zebrafish, larval and adult Drosophila, mice and xenopus. Sample tracking videos can be viewed online of zebrafish, Drosophila and mice.

Zebrafish

The zebrafish (Danio rerio) is a popular model organism in biomedical research which allows for the study of mechanisms at the genetic, cellular and developmental level, through rapid characterisation of behavioural phenotyping and mutant lines (Mathur & Guo, 2010). Alongside practical qualities such as their small size, quick reproduction and short generation time, their external fertilisation and transparent embryo enables in vivo monitoring during early-stage development. This accessibility allows for easy manipulation on the developing embryo both genetically and pharmacologically, providing an in vivo animal model for high-throughput screens to identify the impact of genetic manipulations or compounds with therapeutic potential.

Zebrafish also share a high degree of genetic and physiological similarity to mammals, including humans. They possess similar major biological and developmental processes and structures with comparative functionality. Their genome is well characterised and its sequencing is complete, showing more than 70% of human genes to have at least one zebrafish orthologue and 84% of genes known to be associated with human disease have a zebrafish counterpart (Howe et al., 2013). Since zebrafish also display a range of behavioural phenotypes that resemble aspects of human disease (Kalueff et al., 2013) they can be used they can be used to study the molecular basis of behaviour (McCarroll, Gendelev, Keiser, & Kokel, 2016).

Zebrafish references

Howe, K., Clark, M., Torroja, C., Torrance, J., Berthelot, C., Muffato, M., … Al., E. (2013). The zebrafish reference genome sequence and its relationship to the human genome. Nature, 496(7446),  498–503.

Kalueff, A. V., Gebhardt, M., Stewart, A. M., Cachat, J. M., Brimmer, M., Chawla, J. S., … Gaikwad, S. (2013). Towards a comprehensive catalog of zebrafish behavior 1.0 and beyond. Zebrafish, 10(1), 70–86.

Mathur, P., & Guo, S. (2010). Use of zebrafish as a model to understand mechanisms of addiction and complex neurobehavioral phenotypes. Neurobiology of Disease, 40(1), 66–72.

McCarroll, M. N., Gendelev, L., Keiser, M. J., & Kokel, D. (2016). Leveraging large-scale behavioral profiling in zebrafish to explore neuroactive polypharmacology. ACS Chemical Biology, 11(4), 842–849.

Drosophila

Drosophila melanogaster, or the fruit-fly is one of the most extensively used model organisms in biomedical research. It has many advantages which has made it ideal to study the molecular mechanisms of behaviour, development and human diseases for more than a century. Drosophila are easy and inexpensive to maintain in the laboratory and breed large numbers of genetically identical progeny. They also have a short generation cycle and life span making large scale, high-throughput genetic screening faster and more effective.

The well-developed genetic techniques and tools available for Drosophila allow investigation and modification of their genes quickly and easily. Drosophila and humans have shared evolutionary roots and many basic biological, physiological, and neurological processes are conserved between humans and Drosophila. They have tissues and organs that are functionally equivalent to mammalian structures (Neckameyer & Argue, 2013). The genome of Drosophila has been fully sequenced and many of the genes present in Drosophila are conserved in humans (Adams et al., 2000). About 75% of human disease-causing genes have an equivalent found in the fly, enabling modelling of many human diseases (Reiter et al., 2001).

In addition, Drosophila have a sophisticated range of behaviours including circadian rhythms, learning and memory, and sleep. Many of the genes and genetic pathways that drive certain behaviours in Drosophila are found to affect similar behaviours in humans, providing a powerful genetic model organism in which to study mechanisms of human disorders.

Drosophila references

Adams, M. D., Celniker, S. E., Holt, R. A., Evans, C. A., Gocayne, J. D., Amanatides, P. G., … & George, R. A. (2000). The genome sequence of Drosophila melanogaster. Science, 287(5461), 2185-2195.

Neckameyer, W. S., & Argue, K. J. (2013). Comparative approaches to the study of physiology: Drosophila as a physiological tool. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 304(3), R177-R188.

Reiter, L. T., Potocki, L., Chien, S., Gribskov, M., & Bier, E. (2001). A systematic analysis of human disease-associated gene sequences in Drosophila melanogaster. Genome research, 11(6), 1114-1125.