Overexpression of a zebrafish homologue of the Drosophila neurogenic gene Delta perturbs differentiation of primary neurons and somite development

• Published in: Mechanisms of development 1997-05, Vol.63 (2), p.159-171
• Main Authors: Dornseifer, Peter, Takke, Christina, Campos-Ortega, José A
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Animals; Brain Stem - metabolism; Cell Differentiation - genetics; Central Nervous System - embryology; Central Nervous System - metabolism; Cloning, Molecular; Delta; Differentiation of primary neurons; Drosophila; Drosophila - genetics; Gene Expression Regulation, Developmental; In Situ Hybridization; Intracellular Signaling Peptides and Proteins; Membrane Proteins - biosynthesis; Membrane Proteins - genetics; Membrane Proteins - physiology; Molecular Sequence Data; Neurons - cytology; Sequence Homology, Amino Acid; Somite development; Somites - physiology; Zebrafish; Zebrafish - embryology; Zebrafish - genetics
• ISSN: 0925-4773; 1872-6356
• DOI: 10.1016/S0925-4773(97)00037-3

We describe here the isolation and characterization of a zebrafish Delta homologue ( deltaD). A PCR fragment was used to obtain overlapping cDNA clones encoding a protein of 717 amino acids with all characteristic features of proteins of this family, a signal peptide, a transmembrane domain, and an extracellular region comprising the DSL domain and eight EGF-like repeats. The gene is transcribed in a complex pattern in the developing nervous system as well as in the hypoblast. Overexpression of this gene following mRNA injections leads to a reduction in the number of islet-1 positive cells, which are assumed to be primary neurons, and to various defects in the adaxial mesoderm, as well as in the somites and myotomes. This suggests that deltaD, and the Notch signalling pathway are involved in the differentiation of primary neurons within the neural plate, as well as in somite development.