Myosin VIIA is a marker for the cone accessory outer segment in zebrafish.

The accessory outer segment, a cytoplasmic structure running alongside the photoreceptor outer segment, has been described in teleost fishes, excluding the model organism zebrafish. So far, the function of the accessory outer segment is unknown. Here, we describe the ultrastructure of the zebrafish cone accessory outer segment by electron microscopy.

The zebrafish mutant bumper shows a hyperproliferation of lens epithelial cells and fibre cell degeneration leading to functional blindness.

The development of the eye lens is one of the classical paradigms of induction during embryonic development in vertebrates. But while there have been numerous studies aimed at discovering the genetic networks controlling early lens development, comparatively little is known about later stages, including the differentiation of secondary lens fibre cells. The analysis of mutant zebrafish isolated in forward genetic screens is an important way to investigate the roles of genes in embryogenesis.

Computer-based analysis of the optokinetic response in zebrafish larvae.

INTRODUCTIONLarge movements in the visual field trigger stereotypic eye movements in vertebrates. This optokinetic response (OKR) is robust in zebrafish (Danio rerio) larvae older than 4 days post-fertilization (dpf), and is hence ideally suited for use in the evaluation of visual performance after genetic manipulations. This protocol describes a simple method by which a computer-generated visual stimulus is projected onto a screen and watched by immobilized larvae.

Time course and development of light adaptation processes in the outer zebrafish retina.

Retinomotor movements are morphological changes in the outer retina in response to changing light conditions. They can be separated into two components: Migration of pigment granules within the microvilli of the retinal pigment epithelium (RPE) and positional changes in photoreceptor cells. These positional changes optimize exposure of the cone and rod photoreceptors to light.