Understanding the elasticity of fibronectin fibrils: Unfolding strengths of FN-III and GFP domains measured by single molecule force spectroscopy

被引:52
作者
Abu-Lail, NI
Ohashi, T
Clark, RL
Erickson, HP [1 ]
Zauscher, S
机构
[1] Duke Univ, Med Ctr, Dept Cell Biol, Durham, NC 27710 USA
[2] Duke Univ, Dept Mech Engn & Mat Sci, Durham, NC 27710 USA
[3] Duke Univ, Ctr Biol Inspired Mat & Mat Syst, Durham, NC 27710 USA
基金
美国国家科学基金会; 美国国家卫生研究院;
关键词
protein unfolding; single molecule force spectroscopy; wormlike chain;
D O I
10.1016/j.matbio.2005.10.007
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
While it is well established that fibronectin (FN) matrix fibrils are elastic, the mechanism of fibril elasticity during extension is still debated. To investigate the molecular origin of FN fibril elasticity, we used single molecule force spectroscopy (SMFS) to determine the unfolding behavior of a recombinant FN-III protein construct that contained eight FN-III domains (1-8FN-III) and two green fluorescent protein (GFP) domains. FN-III domains were distinguished from GFP domains by their shorter unfolding lengths. The unfolding strengths of both domains were determined for a wide range of pulling rates (50 to 1745 nm/s). We found that the mechanical stabilities of FN-III and GFP domains were very similar to each other over the entire range of pulling speeds. FN fibrils containing GFP remain brightly fluorescent, even when stretched, meaning that GFP domains remain largely folded. Since GFP and FN-III have equal unfolding strengths, this suggests that FN-III domains are not extensively unraveled in stretched FN fibrils. Our results thus favor an alternative model, which invokes a conformational change from a compact to an extended conformation, as the basis for FN fibril elasticity. (c) 2005 Elsevier B.V./International Society of Matrix Biology. All rights reserved.
引用
收藏
页码:175 / 184
页数:10
相关论文
共 41 条
[1]  
Alberts B., 2002, Molecular Biology of The Cell, V4th
[2]   Fibronectin extension and unfolding within cell matrix fibrils controlled by cytoskeletal tension [J].
Baneyx, G ;
Baugh, L ;
Vogel, V .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2002, 99 (08) :5139-5143
[3]   Coexisting conformations of fibronectin in cell culture imaged using fluorescence resonance energy transfer [J].
Baneyx, G ;
Baugh, L ;
Vogel, V .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2001, 98 (25) :14464-14468
[4]   Can non-mechanical proteins withstand force? Stretching barnase by atomic force microscopy and molecular dynamics simulation [J].
Best, RB ;
Li, B ;
Steward, A ;
Daggett, V ;
Clarke, J .
BIOPHYSICAL JOURNAL, 2001, 81 (04) :2344-2356
[5]   PROPOSED ACQUISITION OF AN ANIMAL PROTEIN DOMAIN BY BACTERIA [J].
BORK, P ;
DOOLITTLE, RF .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1992, 89 (19) :8990-8994
[6]   ENTROPIC ELASTICITY OF LAMBDA-PHAGE DNA [J].
BUSTAMANTE, C ;
MARKO, JF ;
SIGGIA, ED ;
SMITH, S .
SCIENCE, 1994, 265 (5178) :1599-1600
[7]   Atomic force microscopy captures length phenotypes in single proteins [J].
Carrion-Vazquez, M ;
Marszalek, PE ;
Oberhauser, AF ;
Fernandez, JM .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1999, 96 (20) :11288-11292
[8]   Mechanical and chemical unfolding of a single protein: A comparison [J].
Carrion-Vazquez, M ;
Oberhauser, AF ;
Fowler, SB ;
Marszalek, PE ;
Broedel, SE ;
Clarke, J ;
Fernandez, JM .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1999, 96 (07) :3694-3699
[9]   Exploring the energy landscape of GFP by single-molecule mechanical experiments [J].
Dietz, H ;
Rief, M .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2004, 101 (46) :16192-16197
[10]  
ERICKSON HP, 1983, J BIOL CHEM, V258, P4539