Regulation of the Cytoskeleton Assembly: a Role for a Ternary Complex of Actin with Two Actin-Binding Proteins

2001 ◽  
pp. 165-179 ◽  
Author(s):  
Murat Kekic ◽  
Neil J. Nosworthy ◽  
Irina Dedova ◽  
Charles A. Collyer ◽  
Cristobal G. dos Remedios
Keyword(s):  
Ternary Complex ◽  
Binding Proteins ◽  
Actin Binding ◽  
Actin Binding Proteins

scholarly journals Mapping the binding site of thymosin β4 on actin by competition with G-actin binding proteins indicates negative co-operativity between binding sites located on opposite subdomains of actin

1997 ◽  
Vol 327 (3) ◽  
pp. 787-793 ◽  
Author(s):  
Edda BALLWEBER ◽  
Ewald HANNAPPEL ◽  
Thomas HUFF ◽  
Hans Georg MANNHERZ
Keyword(s):  
Binding Site ◽  
Binding Sites ◽  
Ternary Complex ◽  
Actin Polymerization ◽  
Binding Proteins ◽  
Critical Concentration ◽  
Dnase I ◽  
Actin Binding ◽  
Thymosin Β4 ◽  
Actin Binding Proteins

The β-thymosins are small monomeric (G-)actin-binding proteins of 5 kDa that are supposed to act intracellularly as actin-sequestering factors stabilizing the cytoplasmic monomeric pool of actin. The binding region of thymosin β4 was determined by analysing the binding of thymosin β4 to actin complexed with DNase I, gelsolin or gelsolin segment 1. Binding was analysed by determining the increase in the critical concentration of actin polymerization by native gel electrophoresis or chemical cross-linking. The formation of a ternary complex including thymosin β4 should indicate that the actin-binding proteins attach to different sites on actin. Competition would be indicative of binding to identical or overlapping sites on actin or of a negative co-operative linkage between the two binding sites. Competition of thymosin β4 for actin binding was observed in the presence of intact gelsolin or the N-terminal gelsolin fragment, segment 1, indicating that thymosin β4 binds to a site close to or identical with the gelsolin segment 1-binding site. The ternary complex of actin-DNase I-thymosin β4 was obtained only when using the chemically cross-linked actin-thymosin β4 complex, indicating that thymosin β4 is dissociated by the binding of DNase I to actin. It is suggested that the dissociation of thymosin β4 by DNase I binding to actin is caused by negative co-operativity between their spatially separated binding sites on actin. A similar negative co-operativity was observed between DNase I and gelsolin segment 1 binding to actin. The results therefore indicate that the respective binding sites for DNase I and segment 1 on subdomains 1 and 2 of actin are linked in a negative co-operative manner.

Actin-binding proteins sensitively mediate actin bundle stiffness

2006 ◽  
Vol 39 ◽  
pp. S240
Author(s):  
M. Bathe ◽  
M. Claessens ◽  
E. Frey ◽  
A. Bausch
Keyword(s):  
Binding Proteins ◽  
Actin Binding ◽  
Actin Binding Proteins ◽  
Actin Bundle

A review of actin binding proteins: new perspectives

2007 ◽  
Vol 36 (1) ◽  
pp. 121-125 ◽  
Author(s):  
Ricardo Uribe ◽  
David Jay
Keyword(s):  
Binding Proteins ◽  
Actin Binding ◽  
Actin Binding Proteins

scholarly journals Actin-Binding Proteins Mediate Regulation by Calcium of Polycystin-2 (tRPP2)

2011 ◽  
Vol 100 (3) ◽  
pp. 106a-107a
Author(s):  
María del Rocío Cantero ◽  
Horacio F. Cantiello
Keyword(s):  
Binding Proteins ◽  
Actin Binding ◽  
Actin Binding Proteins

Viscoelastic Properties of F-Actin Solutions in the Presence of Normal and Mutated Actin-Binding Proteins

1996 ◽  
Vol 325 (2) ◽  
pp. 183-189 ◽  
Author(s):  
K.-P. Janssen ◽  
L. Eichinger ◽  
P.A. Janmey ◽  
A.A. Noegel ◽  
M. Schliwa ◽  
...  
Keyword(s):  
Viscoelastic Properties ◽  
Binding Proteins ◽  
Actin Binding ◽  
Actin Binding Proteins

Actin-binding proteins are conserved from slime molds to man

1988 ◽  
Vol 9 (4-5) ◽  
pp. 521-530 ◽  
Author(s):  
Michael Schleicher ◽  
Elisabeth André ◽  
Herbert Hartmann ◽  
Angelika A. Noegel
Keyword(s):  
Binding Proteins ◽  
Actin Binding ◽  
Actin Binding Proteins ◽  
Slime Molds

scholarly journals Ultrastructure of the yeast actin cytoskeleton and its association with the plasma membrane.

1994 ◽  
Vol 125 (2) ◽  
pp. 381-391 ◽  
Author(s):  
J Mulholland ◽  
D Preuss ◽  
A Moon ◽  
A Wong ◽  
D Drubin ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Actin Cytoskeleton ◽  
Binding Proteins ◽  
Ultrastructural Level ◽  
Actin Binding ◽  
Cortical Actin ◽  
Actin Binding Proteins ◽  
Double Labeling ◽  
Wall Growth ◽  
Cortical Cytoskeleton

We characterized the yeast actin cytoskeleton at the ultrastructural level using immunoelectron microscopy. Anti-actin antibodies primarily labeled dense, patchlike cortical structures and cytoplasmic cables. This localization recapitulates results obtained with immunofluorescence light microscopy, but at much higher resolution. Immuno-EM double-labeling experiments were conducted with antibodies to actin together with antibodies to the actin binding proteins Abp1p and cofilin. As expected from immunofluorescence experiments, Abp1p, cofilin, and actin colocalized in immuno-EM to the dense patchlike structures but not to the cables. In this way, we can unambiguously identify the patches as the cortical actin cytoskeleton. The cortical actin patches were observed to be associated with the cell surface via an invagination of plasma membrane. This novel cortical cytoskeleton-plasma membrane interface appears to consist of a fingerlike invagination of plasma membrane around which actin filaments and actin binding proteins are organized. We propose a possible role for this unique cortical structure in wall growth and osmotic regulation.

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