Complexes between 15 kDa caldesmon fragment and actin investigated by immuno-electron microscopy.
FEBS Lett
; 269(1): 185-8, 1990 Aug 20.
Article
em En
| MEDLINE
| ID: mdl-2387400
ABSTRACT
The regulatory system of smooth muscle thin filaments is thought to involve a major calcium-calmodulin and actin binding protein caldesmon. A dissective approach was used to isolate a 35 kDa C-terminal fragment of the molecule and to produce antibodies reacting against both the intact and the 15 kDa N-terminal end of this parental fragment. While this purified 15 kDa caldesmon fragment demonstrates a weak actin association, we observed that it cross-links actin filaments into loose bundles. These structures were labelled with a selective antibody and showed regular periodic striation with repeats of approximately 40 nm. This work brings additional information to previous reports using an actin and calmodulin binding 25 kDa C-terminal fragment of the caldesmon molecule [(1989) J. Biol. Chem. 264, 2869-2875]. We demonstrate that a purified fragment corresponding to a sequence smaller than 96 amino acids, which contains no cystein residue, is able to interact with actin at a single site which is not the calmodulin modulated.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Ligação a Calmodulina
/
Actinas
/
Proteínas dos Microfilamentos
Limite:
Animals
Idioma:
En
Ano de publicação:
1990
Tipo de documento:
Article