Neurogenetic asymmetries in the catshark developing habenulae: mechanistic and evolutionary implications.
Sci Rep
; 8(1): 4616, 2018 03 15.
Article
em En
| MEDLINE
| ID: mdl-29545638
ABSTRACT
Analysis of the establishment of epithalamic asymmetry in two non-conventional model organisms, a cartilaginous fish and a lamprey, has suggested that an essential role of Nodal signalling, likely to be ancestral in vertebrates, may have been largely lost in zebrafish. In order to decipher the cellular mechanisms underlying this divergence, we have characterised neurogenetic asymmetries during habenular development in the catshark Scyliorhinus canicula and addressed the mechanism involved in this process. As in zebrafish, neuronal differentiation starts earlier on the left side in the catshark habenulae, suggesting the conservation of a temporal regulation of neurogenesis. At later stages, marked, Alk4/5/7 dependent, size asymmetries having no clear counterparts in zebrafish also develop in neural progenitor territories, with a larger size of the proliferative, pseudostratified neuroepithelium, in the right habenula relative to the left one, but a higher cell number on the left of a more lateral, later formed population of neural progenitors. These data show that mechanisms resulting in an asymmetric, preferential maintenance of neural progenitors act both in the left and the right habenulae, on different cell populations. Such mechanisms may provide a substrate for quantitative variations accounting for the variability in size and laterality of habenular asymmetries across vertebrates.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Regulação da Expressão Gênica no Desenvolvimento
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Habenula
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Embrião não Mamífero
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Evolução Biológica
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Neurogênese
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Lateralidade Funcional
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article