A Go-To Resource Center for Zebrafish Researchers
Since making its debut as a research organism in the late 1970s, the humble zebrafish—an unassuming, pinky-sized striped fish originally found in the freshwaters of the Himalayas—has gained significant traction as a valuable tool among genetics and other biomedical researchers. In 1999, this small-sized fish was bestowed with a full-service resource center, established in Eugene, Oregon, with support from the National Institutes of Health (NIH). The Zebrafish International Resource Center (ZIRC) has become NIH’s flagship zebrafish repository and resource center, and the zebrafish (Danio rerio) has ascended to become a mainstream model organism, akin to such vertebrates as the mouse (Mus musculus) and the frog (Xenopus spp.) as well as such invertebrates as the fruit fly (Drosophila melanogaster) and the roundworm (Caenorhabditis elegans), among others.
Why use zebrafish? Zebrafish share a very similar physiology and genome with humans. For 82% of the disease genes known in humans so far, scientists have discovered an ortholog in zebrafish1–a gene that evolved from a shared ancestral gene. Such genetic similarity gives scientists the power to study various aspects of human disease in a non-human organism. Zebrafish are able to quickly produce a large amount of offspring, and their embryos develop very rapidly and are transparent. When scientists incorporate the use of fluorescent imaging techniques into their work, they are able to see and study cellular and molecular processes that are taking place in real time within the animal. Together, these attributes lend themselves particularly well to research in the fields of developmental biology, genetics, neurobiology, regenerative medicine, cancer biology, and others. Zebrafish also are far less costly to maintain in laboratories than are larger vertebrates, making zebrafish a highly attractive organism in which to conduct research.
ZIRC is home to more than 30,000 genetic strains of zebrafish used in research laboratories around the world—an incredible amount considering that initially the facility housed only a couple dozen strains. The strains are of both wild-type and mutant zebrafish, and ZIRC prioritizes keeping a close eye on biosecurity and health monitoring in their repository2. Researchers around the world can order any of these strains to use for their work, or they can submit strains they have generated in their own laboratories for preservation as cryopreserved sperm samples in liquid nitrogen containers at ZIRC, thereby reducing duplicative efforts across laboratories. ZIRC also offers for purchase other types of biological molecules, including expressed sequence tags (ESTs), complementary DNAs (cDNAs), and monoclonal antibodies.
Scientists are encouraged to take advantage of ZIRC’s extensive library of information and resources on zebrafish research and husbandry. ZIRC even has an in-house program on developing effective and improved cryopreservation methodologies. Researchers can access ZIRC’s pathology and consultation services, which are designed to assist researchers in diagnosing and treating diseases that may be affecting the zebrafish in their laboratories. Additionally, ZIRC investigates how to minimize the extent to which pathogens, such as bacteria and fungi, that are commonly found in captive colonies compromise scientific outcomes; these pathogens may be important causes of non-protocol variation on research endpoints. Finally, in addition to their technical services, ZIRC offers a range of outreach and education activities. ZIRC’s wide suite of services truly makes it a full-service resource center for scientists using zebrafish in their research laboratories.
References
1 Howe K, Clark MD, Torroja CF, Torrance J, Berthelot C, Muffato M, Collins JE, Humphray S McLaren K, Matthews L, et al. The zebrafish reference genome sequence and its relationship to the human genome. Nature. 2013;496:498–503.
2 Murray KN, Varga ZM, Kent, ML. Biosecurity and health monitoring at the Zebrafish International Resource Center. Zebrafish. 2016;13:S-30–S-38.