Titre : | Adhesion proteins in myoblasts fusion (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) ; Brzoska E. ; Wrobel E ; Moraczewski J |
Type de document : | Article |
Année de publication : | 2005 |
Pages : | p. 75 |
Langues: | Anglais |
Mots-clés : | adhérence cellulaire ; colloque ; culture cellulaire ; différenciation musculaire ; fusion cellulaire ; intégrine ; M-cadhérine ; matrice extracellulaire ; meltrine ; molécule d'adhérence cellulaire ; muscle squelettique ; myoblaste ; myogenèse ; syndécane |
Résumé : |
Communication n° 243. Introduction : Cell-extracellular matrix and cell-cell adhesion play essential roles during myogenesis. Several adhesion proteins were postulated to play a role in this process and among them are: integrin a3ß1, M-cadherin, ADAM12, syndecan-4. We examined the participation of these molecules during primary myoblasts differentiation in vitro. Satelitte cells that serve as myogenic precursors cells and participate in post-natal muscle growth and regeneration, were isolated from the adult animals skeletal muscles and cultured in vitro. Methods : The primary myoblasts cultures were grown under standart conditions. During myoblasts differentiation we studied: the localization of proteins (immunolocalization, confocal microscopy), mRNA and protein level (immunoblotting, RT-PCR), co-immunoprecipitation of integrin a3ß1, M-cadherin, ADAM12 and syndecan-4, the fusion index in cultures with the presence of specific antibodies against extracellular domains of named proteins and the overexpresion of integrin a3 subunit. Results : We showed that intrgrin a3 subunit and syndecan-4 were expressed in quiescent satellite cells and activated myoblasts. We noticed that myoblastas differentiation was accompanied by the increase in protein and mRNA encoding integrin a3 subunit, integrin ß1 subunit, ADAM12 and M-cadherin. Moreover, M-cadherin, ADAM12 and integrin a3 subunit were accumulated at the contact areas between fusing myoblasts. In the presence of antibodies against extracellular domains of syndecan-4, the myoblast adhesion was disturbed. Myoblast culture in the presence of antibodies against M-cadherin, integrin a3 subunit and integrin ß1subunit lead the inhibition of their fusion. Overexpresion of full lenght integrin a3 subunit induced myoblast fusion. In addition, during myoblast fusion integrin a3 subunit was shown to coimmunoprecipitate with integrin ß1 subunit and ADAM12. Conclusions : 1.Syndecan-4, ADAM12, integrin a3ß1 and ADAM12 are involved in myoblast differentiation. 2.Syndecan-4 plays mediates in myoblasts adhesion and proliferation. 3.M-cadherin, integrin a3ß1 and ADAM12 complexes participate in cell-cell adhesion and these proteins form pre-fusion complex engaged in myoblast fusion. |