Untangling posterior growth and segmentation by analyzing mechanisms of axis elongation in hemichordates.
Proc Natl Acad Sci U S A
; 116(17): 8403-8408, 2019 04 23.
Article
em En
| MEDLINE
| ID: mdl-30967509
ABSTRACT
The trunk is a key feature of the bilaterian body plan. Despite spectacular morphological diversity in bilaterian trunk anatomies, most insights into trunk development are from segmented taxa, namely arthropods and chordates. Mechanisms of posterior axis elongation (PAE) and segmentation are tightly coupled in arthropods and vertebrates, making it challenging to differentiate between the underlying developmental mechanisms specific to each process. Investigating trunk elongation in unsegmented animals facilitates examination of mechanisms specific to PAE and provides a different perspective for testing hypotheses of bilaterian trunk evolution. Here we investigate the developmental roles of canonical Wnt and Notch signaling in the hemichordate Saccoglossus kowalevskii and reveal that both pathways play key roles in PAE immediately following the completion of gastrulation. Furthermore, our functional analysis of the role of Brachyury is supportive of a Wnt-Brachyury feedback loop during PAE in S. kowalevskii, establishing this key regulatory interaction as an ancestral feature of deuterostomes. Together, our results provide valuable data for testing hypotheses of bilaterian trunk evolution.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Cordados não Vertebrados
/
Regulação da Expressão Gênica no Desenvolvimento
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Padronização Corporal
Limite:
Animals
Idioma:
En
Revista:
Proc Natl Acad Sci U S A
Ano de publicação:
2019
Tipo de documento:
Article