The gelsolin:calponin complex nucleates actin filaments with distinct morphologies.

Imen Ferjani (1, 2) , Abdellatif Fattoum (3) , Nadir Bettache (3) , Bastien Seantier (4) , Pierre-Emmanuel Milhiet (4) , Mohamed Manai (2) , Yves Benyamin (1) , Claude Roustan (1) , Sutherland K Maciver (5)

1 DIMNP - Dynamique des interactions membranaires normales et pathologiques
2 Unité de Biochimie et Biologie Moléculaire
3 CRBM - Centre de recherche en Biologie Cellulaire
4 CBS - Centre de Biochimie Structurale [Montpellier]
5 Centre for Integrative Physiology

Gelsolin and calponin are cytoskeletal and signalling proteins that form a tight 1:1 complex (GCC). We show that calponin within the GCC inhibits the rate of gelsolin mediated nucleation of actin polymerization. The actin-binding function of calponin is ablated within the GCC as the actin-binding site overlaps with one of the gelsolin binding sites. The structure of filaments that result from nucleation by GCC are different to those nucleated by gelsolin alone in that they are longer, loosely bundled and stain heterogeneously with phalloidin. GCC nucleated filaments appear contorted and wrap around each to form the loose bundles.

Domaines: Biochimie, Biologie Moléculaire

Imen Ferjani, Abdellatif Fattoum, Nadir Bettache, Bastien Seantier, Pierre-Emmanuel Milhiet, et al.. The gelsolin:calponin complex nucleates actin filaments with distinct morphologies.. Biochemical and Biophysical Research Communications, 2010, 392 (2), pp.118-23. ⟨10.1016/j.bbrc.2009.12.103⟩. ⟨hal-00491991⟩