Ionic currents are critical for the functioning of the inner ear auditory sensory epithelium. We set out to identify and molecularly clone the genes encoding the channels responsible for several currents in the chick basilar papilla. Here we describe an inward-rectifying K+ channel, cKir2.3, present in both hair cells and support cells in the apical end of the chick basilar papilla. The biophys...

A comparative study on tumorigenicity was carried out in which two Epstein-Barr virus (EBV) genome-positive epithelial cell lines (A2L/AH and NPC-KT) were tested in nude mice xenograft system and chick embryo system. When two cell lines were inoculated subcutaneously in nude mice and on chorioallantonic membrane of the chick embryo, respectively, tumors developed in both systems. Histologically...

Cartilage formation in the chick limb follows rapid proliferation, condensation and differentiation of limb mesenchyme. The control of these early events is poorly understood. Platelet-derived growth factor receptor alpha (PDGFR-alpha) is present throughout the mesenchyme of early chick limb buds, while its ligand, PDGF-A, is expressed in the surrounding epithelium. PDGFR-alpha is down-regulate...

Developmental biology research has used various avian species as model organisms for studying morphogenesis, with the chick embryo being used by the majority of groups. The focus on the chick embryo led Hamburger and Hamilton to develop their definitive staging series nearly 60 years ago and this series is still the mainstay of all laboratories working with avian embryos. The focus on the chick...

During breeding, animal behaviour is particularly sensitive to environmental and food resource availability. Additionally, factors such as sex, body condition, and offspring developmental stage can influence behaviour. Amongst seabirds, behaviour is generally predictably affected by local foraging conditions and has therefore been suggested as a potentially useful proxy to indicate prey state. ...

The fate map of the early neural plate and neural fold has been established at the cephalic level by using the quail-chick marker system (Le Douarin, 1969,1973). The experimental design comprised the replacement of definite territories belonging to the neural plate and neural folds in the chick embryo by their counterparts from quail embryos at the same developmental stage. This technique is re...

An assay capable of recovering individual viable rodent cells localized in various organs of the chick embryo is described. This assay is based on the differential sensitivity of chick and rodent cells to the cytotoxic drug ouabain. Utilizing this assay, the potential of the chick embryo as a model system for studying metastasis was examined. Several cell lines were characterized in three ways:...

Patterning of fast and slow muscle fibres in limbs is regulated by signals from non-muscle cells. Myoblast lineage has, however, also been implicated in fibre type patterning. Here we test a founder cell hypothesis for the role of myoblast lineage, by implanting characterized fast and slow mouse myoblast clones into chick limb buds. In culture, late foetal mouse myoblast clones are committed to...

Patterning of the chick telencephalon has been debated, especially in regard to a ventral (subpallial) or dorsal (pallial) nature of the dorsal ventricular ridge (DVR). Here we report the expression patterns of chick homologues of molecules known to be involved in telencephalic patterning in other vertebrate species. We show here that the transcription factors Ngn1, Ngn2, Cash1, Gsh2 and the se...

In a cross species in vitro assay, growth cones from fish temporal retina elongating on laminin lanes were observed with time-lapse videomicroscopy as they encountered lanes and territories that carried membrane fragments from the chick caudal tectum. Caudal tectal membranes of adult fish and embryonic chick are known to possess a repellent guiding component for temporal retinal axons. The caud...