Titre :
|
Expression and function of XMRF4 during Xenopus embryogenesis (abstract : congrès international de Myologie, 2005)
|
contenu dans :
|
|
Auteurs :
|
Congrès international de myologie 2005 (International Congress of Myology 2005; 9-13 mai 2005; Nantes, France) ;
della Gaspera B ;
Sequeira I ;
Chanoine C
|
Type de document :
|
Article
|
Année de publication :
|
2005
|
Pages :
|
p. 77
|
Langues:
|
Anglais
|
Mots-clés :
|
acide aminé (chimie)
;
adulte
;
colloque
;
embryogenèse
;
facteur Myf-5
;
MyoD
;
régénération musculaire
;
somite
;
xénope
|
Résumé :
|
Communication n° 362. We have cloned and sequenced the two full length Xenopus laevis XMRF4a and XMRF4b cDNAs respectively coding for two polypeptides of 239 and 240 amino acid residues. These two mRNA are expressed at different levels during embryogenesis, regeneration and in the adult muscles. During embryogenesis, XMRF4 expression is initiated after MyoD and Myf5 at stage 18 at the same time as differentiation occurs in the somitic cells. The polyclonal affinity-purified antibody detected the protein in the nuclei just after the corresponding mRNA could be detected. Unilateral injection of a synthetic mRNA encoding a dominant negative form of XMRF4 inhibited the expresion of larval MHC E3 to a much lesser extent than with a dominant negative form of Myf5. Activation of an inducible XMRF4 protein modifies the spatio temporal expression pattern of the gamma subunit gene of acetyl choline receptor. The change of expression pattern is different with inducible form of MyoD. In these experiments, inducible proteins are translated in embryos after unilateral injection of mRNA at the two cells stage. These results suggest that MRF4 exerts a specific effect on the expression of target muscular genes in vivo.
|