Detection and characterization of molecular interfaces of FXIII-Fibrinogen complex by employing integrative hybrid approaches

采用综合混合方法检测和表征 FXIII-纤维蛋白原复合物的分子界面

• 批准号: 457324851
• 负责人: Dr. Sneha Singh
• 金额: --
• 依托单位: Institut für Experimentelle Hämatologie und Transfusionsmedizin (IHT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/457324851?language=en
• 关键词: Detection; characterization; molecular; interfaces; FXIII

The intrinsic and extrinsic pathways of coagulation pathway converge terminally to a common pathway that involves strong role of plasma transglutaminase Factor XIII (FXIII), towards covalent crosslinking of pre-formed fibrin clots, imparting it mechanical strength. A blood-clot is a massive mass of fibrin fibers, precipitating platelets, RBCs, complement, and inflammatory components making it a condensed mass of material that further ensues cessation of bleeding by clump formation and wound healing as a result of activated inflammation. Coagulation Factor XIII is responsible for not just condensing this fibrin mass, but also tethering diverse plasma components onto the clot because of its transglutaminase activity. A conspectus view of these molecules, their roles and behavior in plasma directly indicates that fibrinogen, the precursor of Fibrin acts as a direct effector protein for clot formation whereas FXIII is its direct modifier. In plasma, there exists an interaction of zymogenic FXIII with fibrinogen, however the exact positions, residues, tethering poses, and the effective strength of this interaction is unknown. Given that these zymogens are abundantly present in plasma there have been reports indicating their direct binding to serum albumin which is likely responsible towards its longevity in plasma. In the present proposal, which is an extension of my last DFG grant, I would like to put forward an attempt to characterize the interaction interfaces among FXIII and Fibrinogen in their native zymogenic states as seen in plasma. This will aide in structural assessment of FXIII-Fibrinogen complex. As a part of the proposal, I would also attempt and I am partially successful in resolving the structure of the native Factor XIII- A2B2 complex, which is not available in totality as yet in the protein databases. Understanding the structural interaction behavior of these proteins in plasma would develop insights towards activation modes of both of them that releases active Fibrin and FXIII-A2 for their action, upon injury. This through structural investigation would reveal surface patches in both the molecules that act as interaction interfaces, mapping under-resolved coagulopathies related to FXIII and Fibrinogen will guide us towards understanding them, and hence towards an improved management and care.

凝血途径的内源性和外源性途径最终汇聚到一个共同的途径，该途径涉及到血浆转谷氨酰胺酶第XIII因子(FXIII)的强大作用，导致预先形成的纤维蛋白凝块的共价交联，赋予其机械强度。血凝块是大量的纤维蛋白纤维，沉淀着血小板、红细胞、补体和炎性成分，使其成为一团凝结的物质，通过凝块形成进一步止血，并因激活的炎症而愈合伤口。凝血因子XIII不仅负责凝结这种纤维蛋白团块，而且由于其转谷氨酰胺酶活性，还将不同的血浆成分捆绑在血栓上。对这些分子及其在血浆中的作用和行为的概述表明，纤维蛋白原是纤维蛋白的前体，是血栓形成的直接影响蛋白，而FXIII是纤维蛋白原的直接修饰物。在血浆中，存在发酵性FXIII与纤维蛋白原的相互作用，但这种相互作用的确切位置、残基、拴系姿势和有效强度尚不清楚。鉴于这些酶原在血浆中大量存在，已有报道表明它们与血清白蛋白直接结合，这可能是其在血浆中长寿的原因。在本提案中，作为我上一次DFG拨款的延伸，我想提出一种尝试，以表征FXIII和纤维蛋白原在其天然产酶状态下的相互作用界面，如在血浆中所见。这将有助于FXIII-纤维蛋白原复合体的结构评估。作为提案的一部分，我还将尝试并部分成功地解析天然因子XIII-A2B2复合体的结构，而蛋白质数据库中尚未完全获得该复合体的结构。了解这些蛋白质在血浆中的结构相互作用行为将有助于深入了解它们在受伤时释放活性纤维蛋白和FXIII-A2的激活模式。通过结构研究，这将揭示作为相互作用界面的两个分子的表面斑块，绘制与FXIII和纤维蛋白原相关的未分解凝血疾病的图谱将引导我们了解它们，从而改善管理和护理。