A model organism is a non-human species that is studied over many years, building up a lot of knowledge about it in order to understand fundamental biological phenomena. The hope is that discoveries made in the model will give insight into how other organisms work.
This strategy is made possible by the similarities of all living organisms. They are similar because of their common descent and the conservation of metabolic and developmental pathways and genes over the course of evolution.
Model organisms in geneticsEdit
Studies of X-linked traits confirmed that genes are found on chromosomes. Studies of linked traits led to the first maps of genetic loci on chromosomes. The first maps of Drosophila chromosomes were done by Alfred Sturtevant.
Drosophila melanogaster is one of the most studied organisms in biological research, particularly in genetics and developmental biology. Its complete genome was sequenced and first published in 2000.
Because great deal is known about its development from egg to larva to adult, it is a key model for developmental genetics, or evo-devo. The hox genes, or homeobox, which control development in metazoa, were worked out first of all in Drosophila.
E. coli was an integral part of the first experiments to understand phage genetics, and early researchers, such as Seymour Benzer, used E. coli and phage T4 to understand the topography of gene structure. Before Benzer's research, it was not known whether the gene was a linear structure, or if it had a branching pattern.
Other model organismsEdit
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- "The Phage Course - origins". Cold Spring Harbor Laboratory. 2006. Retrieved 2007-12-03.
- Benzer, Seymour (March 1961). "On the topography of the genetic fine structure". PNAS 47 (3): 403–15. doi:10.1073/pnas.47.3.403. PMC 221592.
- Frederick R. Blattner et al. (September 5 1997). "The complete genome sequence of Escherichia coli K-12". Science 277 (5331): 1453–1462. doi:10.1126/science.277.5331.1453. PMC 9278503.
- Bacteria make major evolutionary shift in the lab New Scientist