Macondo crude oil from the Deepwater Horizon oil spill disrupts specific developmental processes during zebrafish embryogenesis.

Unlabelled: The Deepwater Horizon disaster was the largest marine oil spill in history, and total vertical exposure of oil to the water column suggests it could impact an enormous diversity of ecosystems. The most vulnerable organisms are those encountering these pollutants during their early life stages. Water-soluble components of crude oil and specific polycyclic aromatic hydrocarbons have been shown to cause defects in cardiovascular and craniofacial development in a variety of teleost species, but the developmental origins of these defects have yet to be determined.

Vincristine and bortezomib cause axon outgrowth and behavioral defects in larval zebrafish.

Peripheral neuropathy is a common side effect of a number of pharmaceutical compounds, including several chemotherapy drugs. Among these are vincristine sulfate, a mitotic inhibitor used to treat a variety of leukemias, lymphomas, and other cancers, and bortezomib, a 26S proteasome inhibitor used primarily to treat relapsed multiple myeloma and mantle cell lymphoma. To gain insight into the mechanisms by which these compounds act, we tested their effects in zebrafish.

Late-stage neuronal progenitors in the retina are radial Müller glia that function as retinal stem cells.

Neuronal progenitors in the mammalian brain derive from radial glia or specialized astrocytes. In developing neural retina, radial glia-like Müller cells are generated late in neurogenesis and are not considered to be neuronal progenitors, but they do proliferate after injury and can express neuronal markers, suggesting a latent neurogenic capacity. To examine the neurogenic capacity of retinal glial cells, we used lineage tracing in transgenic zebrafish with a glial-specific promoter (gfap, for glial fibrillary acid protein) driving green fluorescent protein in differentiated Müller glia.

Molecular characterization of retinal stem cells and their niches in adult zebrafish.

Background: The persistence in adult teleost fish of retinal stem cells that exhibit all of the features of true 'adult stem cells'--self-renewal, multipotency, and the capacity to respond to injury by mitotic activation with the ability to regenerate differentiated tissues--has been known for several decades. However, the specialized cellular and molecular characteristics of these adult retinal stem cells and the microenvironmental niches that support their maintenance in the differentiated retina and regulate their activity during growth and regeneration have not yet been elucidated.

Results: Our data show that the zebrafish retina has two kinds of specialized niches that sustain retinal stem cells: 1) a neuroepithelial germinal zone at the interface between neural retina and ciliary epithelium, called the ciliary marginal zone (CMZ), a continuous annulus around the retinal circumference, and 2) the microenvironment around some Müller glia in the differentiated retina.

GFAP transgenic zebrafish.

We have generated transgenic zebrafish that express green fluorescent protein (GFP) in glial cells driven by the zebrafish glial fibrillary acidic protein (GFAP) regulatory elements. Transgenic lines Tg(gfap:GFP) were generated from three founders; the results presented here are from the mi2001 line. GFP expression was first visible in the living embryo at the tail bud-stage, then in the developing brain by the 5-somite-stage ( approximately 12 h post-fertilization, hpf) and then spreading posteriorly along the developing spinal cord by the 12-somite stage (approximately 15 hpf).