Direct measurement of critical concentrations and assembly rate constants at the two ends of an actin filament

Edward Bonder, Douglas J. Fishkind, Mark S. Mooseker

Research output: Contribution to journalArticle

82 Citations (Scopus)

Abstract

Actin filament bundles isolated from Limulus sperm were used for quantitative electron microscope studies of F-actin assembly. The assembly rate constants were calculated. In addition, the critical concentrations (Cos) for both filament ends were directly determined. In 75 mM KCI and 1-5 mM Mg++, the Cos were 0.1 μM and 0.5 μM for the barbed and pointed ends, respectively. Substitution of Ca++ (20-200 μM) for Mg++ resulted in Cos of 0.4 μM for both filament ends. Consistent with these findings, filament growth occurred only from the barbed ends of Limulus bundles "seeded" into F-actin solutions in KCI and Mg++. Finally, filaments originally grown from the pointed filament ends of Limulus bundles were gradually lost as the actin solution reached steady state. These results demonstrate that actin filaments can "treadmill" under physiological conditions, albeit at very slow rates.

Original languageEnglish (US)
Pages (from-to)491-501
Number of pages11
JournalCell
Volume34
Issue number2
DOIs
StatePublished - Jan 1 1983
Externally publishedYes

Fingerprint

Horseshoe Crabs
Actin Cytoskeleton
Actins
Rate constants
Spermatozoa
Exercise equipment
Electrons
Growth
Substitution reactions
Electron microscopes

All Science Journal Classification (ASJC) codes

  • Biochemistry, Genetics and Molecular Biology(all)

Cite this

Bonder, Edward ; Fishkind, Douglas J. ; Mooseker, Mark S. / Direct measurement of critical concentrations and assembly rate constants at the two ends of an actin filament. In: Cell. 1983 ; Vol. 34, No. 2. pp. 491-501.
@article{af1ca05a08d9406284475f8ac0087361,
title = "Direct measurement of critical concentrations and assembly rate constants at the two ends of an actin filament",
abstract = "Actin filament bundles isolated from Limulus sperm were used for quantitative electron microscope studies of F-actin assembly. The assembly rate constants were calculated. In addition, the critical concentrations (Cos) for both filament ends were directly determined. In 75 mM KCI and 1-5 mM Mg++, the Cos were 0.1 μM and 0.5 μM for the barbed and pointed ends, respectively. Substitution of Ca++ (20-200 μM) for Mg++ resulted in Cos of 0.4 μM for both filament ends. Consistent with these findings, filament growth occurred only from the barbed ends of Limulus bundles {"}seeded{"} into F-actin solutions in KCI and Mg++. Finally, filaments originally grown from the pointed filament ends of Limulus bundles were gradually lost as the actin solution reached steady state. These results demonstrate that actin filaments can {"}treadmill{"} under physiological conditions, albeit at very slow rates.",
author = "Edward Bonder and Fishkind, {Douglas J.} and Mooseker, {Mark S.}",
year = "1983",
month = "1",
day = "1",
doi = "10.1016/0092-8674(83)90382-3",
language = "English (US)",
volume = "34",
pages = "491--501",
journal = "Cell",
issn = "0092-8674",
publisher = "Cell Press",
number = "2",

}

Direct measurement of critical concentrations and assembly rate constants at the two ends of an actin filament. / Bonder, Edward; Fishkind, Douglas J.; Mooseker, Mark S.

In: Cell, Vol. 34, No. 2, 01.01.1983, p. 491-501.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Direct measurement of critical concentrations and assembly rate constants at the two ends of an actin filament

AU - Bonder, Edward

AU - Fishkind, Douglas J.

AU - Mooseker, Mark S.

PY - 1983/1/1

Y1 - 1983/1/1

N2 - Actin filament bundles isolated from Limulus sperm were used for quantitative electron microscope studies of F-actin assembly. The assembly rate constants were calculated. In addition, the critical concentrations (Cos) for both filament ends were directly determined. In 75 mM KCI and 1-5 mM Mg++, the Cos were 0.1 μM and 0.5 μM for the barbed and pointed ends, respectively. Substitution of Ca++ (20-200 μM) for Mg++ resulted in Cos of 0.4 μM for both filament ends. Consistent with these findings, filament growth occurred only from the barbed ends of Limulus bundles "seeded" into F-actin solutions in KCI and Mg++. Finally, filaments originally grown from the pointed filament ends of Limulus bundles were gradually lost as the actin solution reached steady state. These results demonstrate that actin filaments can "treadmill" under physiological conditions, albeit at very slow rates.

AB - Actin filament bundles isolated from Limulus sperm were used for quantitative electron microscope studies of F-actin assembly. The assembly rate constants were calculated. In addition, the critical concentrations (Cos) for both filament ends were directly determined. In 75 mM KCI and 1-5 mM Mg++, the Cos were 0.1 μM and 0.5 μM for the barbed and pointed ends, respectively. Substitution of Ca++ (20-200 μM) for Mg++ resulted in Cos of 0.4 μM for both filament ends. Consistent with these findings, filament growth occurred only from the barbed ends of Limulus bundles "seeded" into F-actin solutions in KCI and Mg++. Finally, filaments originally grown from the pointed filament ends of Limulus bundles were gradually lost as the actin solution reached steady state. These results demonstrate that actin filaments can "treadmill" under physiological conditions, albeit at very slow rates.

UR - http://www.scopus.com/inward/record.url?scp=0020825184&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0020825184&partnerID=8YFLogxK

U2 - 10.1016/0092-8674(83)90382-3

DO - 10.1016/0092-8674(83)90382-3

M3 - Article

C2 - 6684506

AN - SCOPUS:0020825184

VL - 34

SP - 491

EP - 501

JO - Cell

JF - Cell

SN - 0092-8674

IS - 2

ER -