A rapid and simple procedure for the isolation and cultivation of fibroblast-like cells from medaka and zebrafish embryos and fin clip biopsies.

In many human diseases, the molecular pathophysiological mechanisms are not understood, which makes the development and testing of new therapeutic approaches difficult. The generation and characterization of animal models such as mice, rats, fruit flies, worms or fish offers the possibility for in detail studies of a disease's development, its course and potential therapies in an organismal context, which considerably minimizes the risk of therapeutic side effects for patients. Nevertheless, due to the high numbers of experimental animals used in research worldwide, attempts to develop alternative test systems will help in reducing their count.

Analysis of cellular behavior and cytoskeletal dynamics reveal a constriction mechanism driving optic cup morphogenesis.

Contractile actomyosin networks have been shown to power tissue morphogenesis. Although the basic cellular machinery generating mechanical tension appears largely conserved, tensions propagate in unique ways within each tissue. Here we use the vertebrate eye as a paradigm to investigate how tensions are generated and transmitted during the folding of a neuroepithelial layer.

Generation of DNA Constructs Using the Golden GATEway Cloning Method.

One of the most frequently executed tasks for molecular biologists is the design and generation of complex DNA constructs. Recently, we established the Golden GATEway cloning kit for the fast and efficient generation of transgenesis vectors. This cloning kit allows the modular assembly of DNA fragments in a defined order.

Hox Function Is Required for the Development and Maintenance of the Drosophila Feeding Motor Unit.

Feeding is an evolutionarily conserved and integral behavior that depends on the rhythmic activity of feeding muscles stimulated by specific motoneurons. However, critical molecular determinants underlying the development of the neuromuscular feeding unit are largely unknown. Here, we identify the Hox transcription factor Deformed (Dfd) as essential for feeding unit formation, from initial specification to the establishment of active synapses, by controlling stage-specific sets of target genes.

A trans-Regulatory Code for the Forebrain Expression of Six3.2 in the Medaka Fish.

A well integrated and hierarchically organized gene regulatory network is responsible for the progressive specification of the forebrain. The transcription factor Six3 is one of the central components of this network. As such, Six3 regulates several components of the network, but its upstream regulators are still poorly characterized.

Distinct roles for BAI1 and TIM-4 in the engulfment of dying neurons by microglia.

The removal of dying neurons by microglia has a key role during both development and in several diseases. To date, little is known about the cellular and molecular processes underlying neuronal engulfment in the brain. Here we took a live imaging approach to quantify neuronal cell death progression in embryonic zebrafish brains and studied the response of microglia.

Close association of olfactory placode precursors and cranial neural crest cells does not predestine cell mixing.

Vertebrate sensory organs originate from both cranial neural crest cells (CNCCs) and placodes. Previously, we have shown that the olfactory placode (OP) forms from a large field of cells extending caudally to the premigratory neural crest domain, and that OPs form through cell movements and not cell division. Concurrent with OP formation, CNCCs migrate rostrally to populate the frontal mass.

Digital scanned laser light-sheet fluorescence microscopy (DSLM) of zebrafish and Drosophila embryonic development.

Embryonic development is one of the most complex processes encountered in biology. In vertebrates and higher invertebrates, a single cell transforms into a fully functional organism comprising several tens of thousands of cells, arranged in tissues and organs that perform impressive tasks. In vivo observation of this biological process at high spatiotemporal resolution and over long periods of time is crucial for quantitative developmental biology.

Differences in vertebrate microRNA expression.

MicroRNAs (miRNAs) attenuate gene expression by means of translational inhibition and mRNA degradation. They are abundant, highly conserved, and predicted to regulate a large number of transcripts. Several hundred miRNA classes are known, and many are associated with cell proliferation and differentiation.

The discovery, positioning and verification of a set of transcription-associated motifs in vertebrates.

We have developed several new methods to investigate transcriptional motifs in vertebrates. We developed a specific alignment tool appropriate for regions involved in transcription control, and exhaustively enumerated all possible 12-mers for involvement in transcription by virtue of their mammalian conservation. We then used deeper comparative analysis across vertebrates to identify the active instances of these motifs.

A first generation physical map of the medaka genome in BACs essential for positional cloning and clone-by-clone based genomic sequencing.

In order to realize the full potential of the medaka as a model system for developmental biology and genetics, characterized genomic resources need to be established, culminating in the sequence of the medaka genome. To facilitate the map-based cloning of genes underlying induced mutations and to provide templates for clone-based genomic sequencing, we have created a first-generation physical map of the medaka genome in bacterial artificial chromosome (BAC) clones. In particular, we exploited the synteny to the closely related genome of the pufferfish, Takifugu rubripes, by marker content mapping.

I-SceI meganuclease mediates highly efficient transgenesis in fish.

The widespread use of fish as model systems is still limited by the mosaic distribution of cells transiently expressing transgenes leading to a low frequency of transgenic fish. Here we present a strategy that overcomes this problem. Transgenes of interest were flanked by two I-SceI meganuclease recognition sites, and co-injected together with the I-SceI meganuclease enzyme into medaka embryos (Oryzias latipes) at the one-cell stage.