Dynamic Role of Cross-Linking Proteins in Actin Rheology

被引：36

作者：

Kim, Taeyoon ^{[2
]}

Hwang, Wonmuk ^{[3
,4
]}

Kam, Roger D. ^{[1
]}

机构：

[1] MIT, Dept Mech & Biol Engn, Cambridge, MA 02139 USA

[2] Univ Chicago, Inst Biophys Dynam, Chicago, IL 60637 USA

[3] Texas A&M Univ, Dept Biomed Engn, College Stn, TX USA

[4] Texas A&M Univ, Mat Sci & Engn Program, College Stn, TX USA

来源：

BIOPHYSICAL JOURNAL | 2011年 / 101卷 / 07期

基金：

美国国家卫生研究院;

关键词：

CYTOSKELETAL POLYMER NETWORKS; VISCOELASTIC PROPERTIES; CELLS; MECHANICS; FILAMIN; STRESS;

D O I：

10.1016/j.bpj.2011.08.033

中图分类号：

Q6 [生物物理学];

学科分类号：

071011 ;

摘要：

We develop a computational model to compare the relative importance of unbinding and unfolding of actin cross-linking proteins (ACPs) in the dynamic properties of the actin cytoskeleton. We show that in the strain-stiffening regime with typical physiological and experimental strain rates, unbinding events are predominant with negligible unfolding. ACPs unbound by greater forces experience larger displacements, with a tendency to rebind to different filaments. At constant strain, stress relaxes to physiological levels by unbinding only-not unfolding-of ACPs, which is consistent with experiments. Also, rebinding of ACPs dampens full relaxation of stress. When the network is allowed to return to a stress-free state after shear deformation, plastic deformation is observed only with unbinding. These results suggest that despite the possibility of unfolding, unbinding of ACPs is the major determinant for the rheology of the actin network.

引用

页码：1597 / 1603

页数：7

共 27 条

[1] Strain hardening, avalanches, and strain softening in dense cross-linked actin networks [J].

Astrom, Jan A. ;

Kumar, P. B. Sunil ;

Vattulainen, Ilpo ;

Karttunen, Mikko .

PHYSICAL REVIEW E, 2008, 77 (05)

[2]

BELL GI, 1978, SCIENCE, V200, P618, DOI 10.1126/science.347575

[3] Filamin cross-linked semiflexible networks: Fragility under strain [J].

DiDonna, B. A. ;

Levine, Alex J. .

PHYSICAL REVIEW LETTERS, 2006, 97 (06)

[4] Scaling the microrheology of living cells [J].

Fabry, B ;

Maksym, GN ;

Butler, JP ;

Glogauer, M ;

Navajas, D ;

Fredberg, JJ .

PHYSICAL REVIEW LETTERS, 2001, 87 (14) :148102/1-148102/4

[5] Measuring molecular rupture forces between single actin filaments and actin-binding proteins [J].

Ferrer, Jorge M. ;

Lee, Hyungsuk ;

Chen, Jiong ;

Pelz, Benjamin ;

Nakamura, Fumihiko ;

Kamm, Roger D. ;

Lang, Matthew J. .

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2008, 105 (27) :9221-9226

[6] Mechanical unfolding of single filamin A (ABP-280) molecules detected by atomic force microscopy [J].

Furuike, S ;

Ito, T ;

Yamazaki, M .

FEBS LETTERS, 2001, 498 (01) :72-75

[7] Stress-dependent elasticity of composite actin networks as a model for cell behavior [J].

Gardel, ML ;

Nakamura, F ;

Hartwig, J ;

Crocker, JC ;

Stossel, TP ;

Weitz, DA .

PHYSICAL REVIEW LETTERS, 2006, 96 (08)

[8] Prestressed F-actin networks cross-linked by hinged filamins replicate mechanical properties of cells [J].

Gardel, ML ;

Nakamura, F ;

Hartwig, JH ;

Crocker, JC ;

Stossel, TP ;

Weitz, DA .

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2006, 103 (06) :1762-1767

[9] Mechanics of actomyosin bonds in different nucleotide states are tuned to muscle contraction [J].

Guo, Bin ;

Guilford, William H. .

PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2006, 103 (26) :9844-9849

[10] Fragility and mechanosensing in a thermalized cytoskeleton model with forced protein unfolding [J].

Hoffman, Brenton D. ;

Massiera, Gladys ;

Crocker, John C. .

PHYSICAL REVIEW E, 2007, 76 (05)

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