Dimerization of profilin II upon binding the (GP5)3 peptide from VASP overcomes the inhibition of actin nucleation by profilin II and thymosin β4

FEBS Letters

Vandekerckhove, Joël¹  Lambrechts, Anja¹  Jonckheere, Veronique¹  Ampe, Christophe¹ 

[1] Flanders Interuniversity Institute of Biotechnology, Department of Biochemistry, Faculty of Medicine, Universiteit Gent, Ledeganckstraat 35, 9000 Ghent, Belgium

关键词: Actin nucleation;    Biacore;    Polyproline;    Profilin isoform;    ENA;    enabled;    F-actin;    filamentous actin;    G-actin;    globular or monomeric actin;    HBS;    HEPES buffer saline;    peptVASPwt;    peptide composed of residues 169–188 of VASP;    peptVASP(G/P);    mutant of the previous peptide in which the glycine residues are substituted to prolines;    peptVASPs;    peptide composed of residues 116–124 of VASP;    PIP2;    l-α-phosphatidylinositol 4;    5-bisphosphate;    RU;    response units;    RUmax;    the experimentally observed maximal response;    RUmaxt;    the theoretical maximal response expected;    VASP;    vasodilator stimulated phosphoprotein;    WASP;    Wiskott-Aldrich syndrome protein;   

DOI  :  10.1016/S0014-5793(99)00293-8

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Profilin II dimers bind the (GP₅)₃ peptide derived from VASP with an affinity of approximately 0.5 μM. The resulting profilin II-peptide complex overcomes the combined capacity of thymosin β4 and profilin II to inhibit actin nucleation and restores the extent of filament formation. We do not observe such an effect when barbed filament ends are capped. Neither can profilin I, in the presence of the peptide, promote actin polymerization during its early phase consistent with a lower affinity. Since a Pro₁₇ peptide-profilin II complex only partially restores actin polymerization, the glycine residues in the VASP peptide appear important.

【 授权许可】

Unknown