Identification of fibrinogen derivatives in the Triton-insoluble residue of human blood platelets.
Identification of fibrinogen derivatives in the Triton-insoluble residue of human blood platelets.
复制标题
人血小板 Triton 不溶性残留物中纤维蛋白原衍生物的鉴定。
DOI：
10.1002/cm.970030103
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Zucker,MB
中科院分区：
文献类型：
--
作者：
Casella,JF;Masiello,NC;Lin,S;Bell,W;Zucker,MB
凝血酶刺激的血小板的三溶性残基中的几种蛋白质（如肌动蛋白、肌凝蛋白和肌动蛋白结合蛋白）在细胞骨架结构的形成中起重要作用。电泳分析表明，凝血酶刺激后，68,000,55,000和48-50,000道尔顿的未知蛋白带也大量存在。由于这些分子量大致对应于纤维蛋白的α， β和γ链，并且由于纤维蛋白原存在于血小板α-颗粒中，因此这些条带与纯化的纤维蛋白原用凝血酶处理，暴露于1% Triton X-100-5 mM EGTA，所得的Triton不溶性残留物沉积时获得的条带进行了比较。68,000-, 55,000-和48- 50,000道尔顿带作为纤维蛋白原衍生物的鉴定是通过在电泳转移到硝化纤维素纸上并用抗纤维蛋白原抗体和125 i -蛋白a处理的血小板的triton不溶性残基的放射自显像中鉴定出来的。此外，如果血小板悬浮液在钙离子存在的情况下用凝血酶处理，观察到因子XIII对纤维蛋白作用的蛋白带特征，活性血小板因子XIII显然是在制备过程中通过裂解血小板而获得的。利用Best等人[1981]最近描述的微管蛋白的电泳特性，对猪脑微管蛋白的迁移研究表明，微管蛋白并不像之前认为的那样大量存在于血小板的不溶性残留物中。这些蛋白作为纤维蛋白原衍生物的鉴定并不能证明纤维蛋白和血小板细胞骨架之间的生理相互作用，因为纤维蛋白是三肽不溶性的，即使在没有血小板细胞骨架的情况下也可以成粒。
Several proteins (eg, actin, myosin, and actin-binding protein) in the Tritoninsoluble residue of thrombin-stimulated platelets are important in the formation of cytoskeletal structures. Electrophoretic analyses have shown that unidentified protein bands of 68,000, 55,000, and 48–50,000 daltons are also present in larger amounts after thrombin stimulation. Since these molecular weights correspond roughly to those of the α, β, and γ chains of fibrin, and since fibrinogen is found in platelet α-granules, these bands were compared to those obtained when purified fibrinogen was treated with thrombin, exposed to 1% Triton X-100-5 mM EGTA, and the resultant Triton-insoluble residue sedimented. Identification of the 68,000-, 55,000-, and 48--50,000-dalton bands as fibrinogen derivatives was confirmed by identifying them in comigration studies and in autoradiographs of Triton-insoluble residues of platelets that were electrophoretically transferred to nitrocellulose paper and treated with antifibrinogen antibody and 125 I-protein A. Furthermore, if the platelet suspension was treated with thrombin in the presence of calcium ions, protein bands characteristic of the action of Factor XIII on fibrin were observed, active platelet Factor XIII apparently having been made available by lysis of platelets during preparation. Making use of the electrophoretic properties of tubulin recently described by Best et al [1981], comigration studies using hog brain tubulin indicated that tubulin is not present in significant amounts in the Triton-insoluble residue of platelets as previously suggested. The identification of these proteins as fibrinogen derivatives does not demonstrate a physiological interaction between fibrin and the platelet cytoskeleton, since fibrin is Tritoninsoluble and can be pelleted even in the absence of platelet cytoskeletons.