Dataset Information

Supernumerary neuromasts in the posterior lateral line of zebrafish lacking peripheral glia.

ABSTRACT: The lateral line and its associated sensory nerves develop from cephalic epithelial thickenings called neurogenic placodes. In the zebrafish, the transcription factor neurogenin 1 is essential for the generation of the sensory ganglion from the placode, but is dispensable for the migration of the primordium and the initial development of neuromasts. We find that inactivation of the gene encoding neurogenin 1 leads to the development of over twice the normal number of neuromasts along the posterior lateral line of zebrafish larvae. Mutation of the gene encoding another transcription factor, sox10, has a similar effect. After a normal number of proneuromasts is initially deposited by the migrating primordia, interneuromast cells divide and differentiate to form the extra neuromasts. Our results indicate that the development of these intercalary neuromasts occurs principally because of the absence of neural crest-derived peripheral glia, which evidently inhibit the assembly of interneuromast cells into neuromasts.

SUBMITTER: Lopez-Schier H

PROVIDER: S-EPMC547829 | biostudies-other | 2005 Feb

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Supernumerary neuromasts in the posterior lateral line of zebrafish lacking peripheral glia.

López-Schier Hernán H Hudspeth A J AJ

Proceedings of the National Academy of Sciences of the United States of America 20050126 5

The lateral line and its associated sensory nerves develop from cephalic epithelial thickenings called neurogenic placodes. In the zebrafish, the transcription factor neurogenin 1 is essential for the generation of the sensory ganglion from the placode, but is dispensable for the migration of the primordium and the initial development of neuromasts. We find that inactivation of the gene encoding neurogenin 1 leads to the development of over twice the normal number of neuromasts along the posteri ...[more]

PMID: 15677337

Similar Datasets

Project description:Hereditary sensory and autonomic neuropathy type 2 (HSNAII) is a rare pathology characterized by an early onset of severe sensory loss (all modalities) in the distal limbs. It is due to autosomal recessive mutations confined to exon "HSN2" of the WNK1 (with-no-lysine protein kinase 1) serine-threonine kinase. While this kinase is well studied in the kidneys, little is known about its role in the nervous system. We hypothesized that the truncating mutations present in the neural-specific HSN2 exon lead to a loss-of-function of the WNK1 kinase, impairing development of the peripheral sensory system. To investigate the mechanisms by which the loss of WNK1/HSN2 isoform function causes HSANII, we used the embryonic zebrafish model and observed strong expression of WNK1/HSN2 in neuromasts of the peripheral lateral line (PLL) system by immunohistochemistry. Knocking down wnk1/hsn2 in embryos using antisense morpholino oligonucleotides led to improper PLL development. We then investigated the reported interaction between the WNK1 kinase and neuronal potassium chloride cotransporter KCC2, as this transporter is a target of WNK1 phosphorylation. In situ hybridization revealed kcc2 expression in mature neuromasts of the PLL and semi-quantitative RT-PCR of wnk1/hsn2 knockdown embryos showed an increased expression of kcc2 mRNA. Furthermore, overexpression of human KCC2 mRNA in embryos replicated the wnk1/hsn2 knockdown phenotype. We validated these results by obtaining double knockdown embryos, both for wnk1/hsn2 and kcc2, which alleviated the PLL defects. Interestingly, overexpression of inactive mutant KCC2-C568A, which does not extrude ions, allowed a phenocopy of the PLL defects. These results suggest a pathway in which WNK1/HSN2 interacts with KCC2, producing a novel regulation of its transcription independent of KCC2's activation, where a loss-of-function mutation in WNK1 induces an overexpression of KCC2 and hinders proper peripheral sensory nerve development, a hallmark of HSANII.

Dataset Information

Supernumerary neuromasts in the posterior lateral line of zebrafish lacking peripheral glia.

Publications

Supernumerary neuromasts in the posterior lateral line of zebrafish lacking peripheral glia.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets