Patterning of brain precursors in ascidian embryos.
Development
; 144(2): 258-264, 2017 01 15.
Article
in En
| MEDLINE
| ID: mdl-27993985
ABSTRACT
In terms of their embryonic origins, the anterior and posterior parts of the ascidian central nervous system (CNS) are associated with distinct germ layers. The anterior part of the sensory vesicle, or brain, originates from ectoderm lineages following a neuro-epidermal binary fate decision. In contrast, a large part of the remaining posterior CNS is generated following neuro-mesodermal binary fate decisions. Here, we address the mechanisms that pattern the anterior brain precursors along the medial-lateral axis (future ventral-dorsal) at neural plate stages. Our functional studies show that Nodal signals are required for induction of lateral genes, including Delta-like, Snail, Msxb and Trp Delta-like/Notch signalling induces intermediate (Gsx) over medial (Meis) gene expression in intermediate cells, whereas the combinatorial action of Snail and Msxb prevents the expression of Gsx in lateral cells. We conclude that despite the distinct embryonic lineage origins within the larval CNS, the mechanisms that pattern neural precursors are remarkably similar.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Urochordata
/
Brain
/
Ciona intestinalis
/
Body Patterning
/
Neural Stem Cells
Limits:
Animals
Language:
En
Journal:
Development
Journal subject:
BIOLOGIA
/
EMBRIOLOGIA
Year:
2017
Document type:
Article
Affiliation country:
Italia