Cell Proliferation and Collective Cell Migration During Zebrafish Lateral Line System Development Are Regulated by Ncam/Fgf-Receptor Interactions.

The posterior lateral line system (pLLS) of aquatic animals comprises small clustered mechanosensory organs along the side of the animal. They develop from proneuromasts, which are deposited from a migratory primordium on its way to the tip of the tail. We here show, that the Neural Cell Adhesion Molecule Ncam1b is an integral part of the pathways initiating and regulating the development of the pLLS in zebrafish.

Drosophila Rhodopsin 7 can partially replace the structural role of Rhodopsin 1, but not its physiological function.

Rhodopsin 7 (Rh7), a new invertebrate Rhodopsin gene, was discovered in the genome of Drosophila melanogaster in 2000 and thought to encode for a functional Rhodopsin protein. Indeed, Rh7 exhibits most hallmarks of the known Rhodopsins, except for the G-protein-activating QAKK motif in the third cytoplasmic loop that is absent in Rh7. Here, we show that Rh7 can partially substitute Rh1 in the outer receptor cells (R1-6) for rhabdomere maintenance, but that it cannot activate the phototransduction cascade in these cells.

Identification and biochemical characterization of two functional CMP-sialic acid synthetases in Danio rerio.

Sialic acids (Sia) form the nonreducing end of the bulk of cell surface-expressed glycoconjugates. They are, therefore, major elements in intercellular communication processes. The addition of Sia to glycoconjugates requires metabolic activation to CMP-Sia, catalyzed by CMP-Sia synthetase (CMAS).

Ncam1a and Ncam1b: two carriers of polysialic acid with different functions in the developing zebrafish nervous system.

Polysialic acid (polySia) is mainly described as a glycan modification of the neural cell adhesion molecule NCAM1. PolySia-NCAM1 has multiple functions during the development of vertebrate nervous systems including axon extension and fasciculation. Phylogenetic analyses reveal the presence of two related gene clusters, NCAM1 and NCAM2, in tetrapods and fishes.

Molecular evolution and expression of zebrafish St8SiaIII, an alpha-2,8-sialyltransferase involved in myotome development.

Enzymes of the St8Sia family, a subgroup of the glycosyltransferases, mediate the transfer of sialic acid to glycoproteins or glycolipids. Here, we describe the cloning of the zebrafish St8SiaIII gene and study its developmental activity. A conserved synteny relationship among vertebrate chromosome regions containing St8SiaIII loci underscores an ancient duplication of this gene in the teleost fish lineage and a specific secondary loss of one paralog in the zebrafish.