The Zebra Fish as a Model Organism in Developmental Biology
The zebra fish as a model organism
The zebra fish (Danio rerio) is easy to breed. Within three days it develops from the egg into a free-swimming alevin. As the zebra fish stays transparent throughout its development, it is an ideal model organism for the microscopical examination of vertebrate organ development.Example 1: The zebra fish in cancer research
In cancer research, the zebra fish is about to take the place of the mouse, which has been the established model organism so far. This is because the developmental cycle of the mouse is longer, and the transparency of its ontogenetic stages lower, than that of the zebra fish. So far, mice have been used that develop cancer cells (e.g., blood cancer) due to genetic changes. These cancer cells are transfected with GFP by means of molecular-biological techniques. The course of the disease can be observed and investigated using the SteREO LUMAR V.12, a fluorescence stereomicroscope of extreme light intensity.Example 2: Disorders of the retina
Degenerative changes of the retina are hereditary human diseases in which light-sensitive receptor cells die - a frequent cause of blindness. Comparable hereditary eye defects can be found in zebra fish. The development of the eye and the connections between the neurofibers in the eye are quite similar in humans and zebra fish. The fast development of the latter makes it possible to observe those degenerative retinal processes with the high-resolution stereomicroscopes SteREO Discovery.V.12 and Lumar V.12 in a quasi-time-lapse mode, and thus to better investigate the cause of the blindness and explore potential therapies. The eyesight of zebra fish alevins is assessed by means of a special test. The stereomicroscope allows the developing eyes of blind and sighted fish to be studied and compared with each other.Strong impetus for zebra fish research
The European Commission has granted €12m to promote studies of the zebra fish model. This is also expected to improve our understanding of the organ development and the diseases of humans as vertebrates. The sum allowed by Brussels is one of the largest grants ever made for a research project in developmental and cell biology.
Zebra fish, three days old
Red and green fluorescence: Antibody-labeled axon populations and GFP-labeled motor neurons
Objective: NeoLumar S 1.5x
Magnification: 150x
Specimen:
Prof. M. Bastmeyer, Dr. M. Marx
Jena, Germany
Friedrich-Schiller- Universität
Micrograph: Dr. M. Zölffel, Carl Zeiss
