RRC ID 389
Author Begemann G, Marx M, Mebus K, Meyer A, Bastmeyer M.
Title Beyond the neckless phenotype: influence of reduced retinoic acid signaling on motor neuron development in the zebrafish hindbrain.
Journal Dev. Biol.
Abstract Retinoic acid (RA) has been identified as a key signal involved in the posteriorization of vertebrate neural ectoderm. The main biosynthetic enzyme responsible for RA signaling in the hindbrain and spinal cord is Raldh2. However, neckless/raldh2-mutant (nls) zebrafish exhibit only mild degrees of anteriorization in the neural ectoderm, compared to full vitamin A deficiency in amniotes and the Raldh2-/- mouse. Here we investigated the role of RA during neuronal development in the zebrafish hindbrain and anterior spinal cord using DEAB, an inhibitor of retinaldehyde dehydrogenases. We show that the nls hindbrain and spinal cord are not fully devoid of RA, since blocking Raldh-mediated RA signaling leads to a more severe hindbrain phenotype than in nls. The anteroposterior distribution of branchiomotor neurons in the facial and more posterior nuclei depends on full RA signaling throughout early and late gastrula stages. In contrast, inhibition of RA synthesis after gastrulation reduces the number of branchiomotor neurons in the vagal nucleus, but has no effect on anteroposterior cell fates. In addition, blockage of RA-mediated signaling not only interferes with the differentiation of branchiomotor neurons and their axons in the hindbrain, but also affects the development of the posterior lateral line nerve.
Volume 271(1)
Pages 119-29
Published 2004-7-1
DOI 10.1016/j.ydbio.2004.03.033
PII S0012160604002490
PMID 15196955
MeSH Aldehyde Oxidoreductases / genetics Aldehyde Oxidoreductases / physiology* Animals Immunohistochemistry In Situ Hybridization Morphogenesis Motor Neurons / physiology* Phenotype* Retinal Dehydrogenase Rhombencephalon / embryology* Signal Transduction / physiology* Tretinoin / physiology Zebrafish / embryology* p-Aminoazobenzene / analogs & derivatives*
IF 2.936
Times Cited 66
Zebrafish rw0