Heterochrony in the regulation of the developing marsupial limb.
Dev Dyn
; 243(2): 324-38, 2014 Feb.
Article
em En
| MEDLINE
| ID: mdl-24115631
ABSTRACT
BACKGROUND:
At birth, marsupial neonates have precociously developed forelimbs. The development of the tammar wallaby (Macropus eugenii) hindlimbs lags significantly behind that of the forelimbs. This differs from the grey short-tailed opossum, Monodelphis domestica, which has relatively similar fore- and hindlimbs at birth. This study examines the expression of the key patterning genes TBX4, TBX5, PITX1, FGF8, and SHH in developing limb buds in the tammar wallaby.RESULTS:
All genes examined were highly conserved with orthologues from opossum and mouse. TBX4 expression appeared earlier in development than in the mouse, but later than in the opossum. SHH expression is restricted to the zone of polarising activity, while TBX5 (forelimb) and PITX1 (hindlimb) showed diffuse mRNA expression. FGF8 is specifically localised to the apical ectodermal ridge, which is more prominent than in the opossum.CONCLUSIONS:
The most marked divergence in limb size in marsupials occurs in the kangaroos and wallabies. The faster development of the fore limb compared to that of the hind limb correlates with the early timing of the expression of the key patterning genes in these limbs.Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Regulação da Expressão Gênica no Desenvolvimento
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Botões de Extremidades
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Padronização Corporal
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Macropodidae
Limite:
Animals
Idioma:
En
Revista:
Dev Dyn
Assunto da revista:
ANATOMIA
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Austrália