Binding of phosphate to F-ADP-actin and role of F-ADP-Pi-actin in ATP-actin polymerization
- PMID: 3335528
Binding of phosphate to F-ADP-actin and role of F-ADP-Pi-actin in ATP-actin polymerization
Abstract
Our previous work (Carlier, M.-F., and Pantaloni, D. (1986) Biochemistry 25, 7789-7792) had shown that F-ADP-Pi-actin is a major intermediate in ATP-actin polymerization, due to the slow rate of Pi release following ATP cleavage on filaments. To understand the mechanism of ATP-actin polymerization, we have prepared F-ADP-Pi-actin and characterized its kinetic parameters. 32Pi binds to F-ADP-actin with a stoichiometry of 1 mol/mol of F-actin subunit and an equilibrium dissociation constant Kpi of 1.5 mM at pH 7.0 Kpi increases with pH, indicating that the H2PO-4 species binds to F-actin. ADP-Pi-actin subunits dissociate much more slowly from filament ends than ADP-actin subunits; therefore, the stability of filaments in ATP is due to terminal ADP-Pi subunits. The slow rate of dissociation of ADP-Pi-actin also explains the decrease in critical concentration of ADP-actin in the presence of Pi reported by Rickard and Sheterline (Richard, J. E., and Sheterline, P. (1986) J. Mol. Biol. 191, 273-280). The effect of Pi on the rate of actin dissociation from filaments is much more pronounced at the barbed end than at the pointed end. Using gelsolin to block the barbed end, we have shown that the two ends are energetically different in the presence of ATP and saturating Pi, but less different than in the absence of Pi. The results are interpreted within a new model for actin polymerization. It is possible that phosphate binding to F-actin can regulate motile events in muscle and nonmuscle cells.
Similar articles
-
Polymerization kinetics of ADP- and ADP-Pi-actin determined by fluorescence microscopy.Proc Natl Acad Sci U S A. 2007 May 22;104(21):8827-32. doi: 10.1073/pnas.0702510104. Epub 2007 May 15. Proc Natl Acad Sci U S A. 2007. PMID: 17517656 Free PMC article.
-
Rate constants for the reactions of ATP- and ADP-actin with the ends of actin filaments.J Cell Biol. 1986 Dec;103(6 Pt 2):2747-54. doi: 10.1083/jcb.103.6.2747. J Cell Biol. 1986. PMID: 3793756 Free PMC article.
-
The interaction between ATP-actin and ADP-actin. A tentative model for actin polymerization.J Biol Chem. 1985 Jun 10;260(11):6572-8. J Biol Chem. 1985. PMID: 3997837
-
Actin polymerization and ATP hydrolysis.Adv Biophys. 1990;26:51-73. doi: 10.1016/0065-227x(90)90007-g. Adv Biophys. 1990. PMID: 2082729 Review.
-
Actin polymerization: regulation by divalent metal ion and nucleotide binding, ATP hydrolysis and binding of myosin.Adv Exp Med Biol. 1994;358:71-81. doi: 10.1007/978-1-4615-2578-3_7. Adv Exp Med Biol. 1994. PMID: 7801813 Review.
Cited by
-
Caenorhabditis elegans gelsolin-like protein 1 is a novel actin filament-severing protein with four gelsolin-like repeats.J Biol Chem. 2008 Sep 19;283(38):26071-80. doi: 10.1074/jbc.M803618200. Epub 2008 Jul 18. J Biol Chem. 2008. PMID: 18640981 Free PMC article.
-
Yeast actin: polymerization kinetic studies of wild type and a poorly polymerizing mutant.Proc Natl Acad Sci U S A. 1996 Jan 9;93(1):91-5. doi: 10.1073/pnas.93.1.91. Proc Natl Acad Sci U S A. 1996. PMID: 8552682 Free PMC article.
-
High microfilament concentration results in barbed-end ADP caps.Biophys J. 1993 Nov;65(5):1757-66. doi: 10.1016/S0006-3495(93)81271-2. Biophys J. 1993. PMID: 8298009 Free PMC article.
-
Multicomponent depolymerization of actin filament pointed ends by cofilin and cyclase-associated protein depends upon filament age.bioRxiv [Preprint]. 2024 Apr 15:2024.04.15.589566. doi: 10.1101/2024.04.15.589566. bioRxiv. 2024. Update in: Eur J Cell Biol. 2024 Jun;103(2):151423. doi: 10.1016/j.ejcb.2024.151423. PMID: 38659736 Free PMC article. Updated. Preprint.
-
Polymerization kinetics of ADP- and ADP-Pi-actin determined by fluorescence microscopy.Proc Natl Acad Sci U S A. 2007 May 22;104(21):8827-32. doi: 10.1073/pnas.0702510104. Epub 2007 May 15. Proc Natl Acad Sci U S A. 2007. PMID: 17517656 Free PMC article.
MeSH terms
Substances
LinkOut - more resources
Full Text Sources
Research Materials
Miscellaneous