Mesodiencephalic dopaminergic (mdDA) neurons originate at the floor plate and floor plate-basal plate boundary of the midbrain ventricular zone. During development mdDA neurons are specified by a unique set of transcription factors and signaling cascades, to form the different molecular subsets of the mdDA neuronal population. In a time series micro-array study performed previously, mesoderm sp...

Two apparently different mechanisms successively contribute to the formation of the neural tube in the avian embryo: bending of the neural plate during the primary neurulation in the cephalo-cervico-thoracic region and cavitation of the medullary cord during the secondary neurulation in the lumbo-sacral region. During both these processes, gastrulation continues by the caudal regression of Hens...

The spinal cord of thoracic, lumbar and caudal levels is derived from a region designated as the sinus rhomboidalis in the 6-somite-stage embryo. Using quail/chick grafts performed in ovo, we show the following. (1) The floor plate and notochord derive from a common population of cells, located in Hensen's node, which is equivalent to the chordoneural hinge (CNH) as it was defined at the tail b...