Polymerization of fibrin:: direct observation and quantification of individual B:b knob-hole interactions
Polymerization of fibrin:: direct observation and quantification of individual B:b knob-hole interactions
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DOI：
10.1182/blood-2006-07-033910
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发表时间：
2007-01-01
期刊：
影响因子：
20.3
通讯作者：
Weisel, John W.
中科院分区：
文献类型：
--
作者：
Litvinov, Rustem I.;Gorkun, Oleg V.;Weisel, John W.
纤维蛋白的聚合主要通过N-末端A-和B-球之间的相互作用发生，所述N-末端A-和B-球分别通过纤维蛋白肽A和B的切割而暴露，以及在γ-和P-模块中的相应a-和b-孔之间。在潜在的旋钮-孔相互作用-A：a、B：B、A：B和B：a中，第一种已被证明对纤维蛋白形成至关重要，但其他的作用仍然难以捉摸。使用激光观察和量化单个B：B和A：B相互作用。具有暴露的A-节的desA-纤维蛋白和具有B-节的desB-纤维蛋白都与来自含有b-孔但没有功能性a-孔的γ D364 H纤维蛋白原的片段D相互作用。发现单个B：B相互作用的强度为15至20 pN，比A：a相互作用弱约6倍。B：B结合被B-节模拟肽、含有2个B-节的（β 15-66）（2）片段和针对β 15-21序列的单克隆抗体消除。desB-纤维蛋白与含有a-和b-孔的片段D的相互作用产生了对A-节模拟肽不敏感的相同的力，这表明不存在B：a相互作用。这些结果首次直接证明了暴露于纤维蛋白单体中的天然B-旋钮介导的B：B结合。
The polymerization of fibrin occurs primarily through interactions between N-terminal A- and B-knobs, which are exposed by the cleavage of fibrinopeptides A and B, respectively, and between corresponding a- and b-holes in the gamma- and P-modules. Of the potential knob-hole interactions-A:a, B:b, A:b, and B:a-the first has been shown to be critical for fibrin formation, but the roles of the others have remained elusive. Using laser observed and quantified individual B:b and A:b interactions. Both desA-fibrin with exposed A-knobs and desB-fibrin bearing B-knobs interacted with fragment D from the gamma D364H fibrinogen containing b-holes but no functional a-holes. The strength of single B:b interactions was found to be 15 to 20 pN, approximately 6-fold weaker than A:a interactions. B:b binding was abrogated by B-knob mimetic peptide, the (beta 15-66)(2) fragment containing 2 B-knobs, and a monoclonal antibody against the beta 15-21 sequence. The interaction of desB-fibrin with fragment D containing a- and b-holes produced the same forces that were insensitive to A-knob mimetic peptide, suggesting that B:a interactions were absent. These results directly demonstrate for the first time B:b binding mediated by natural B-knobs exposed in a fibrin monomer.