Role of Charcot-Leyden Crystal Protein in Eosinophils

描述(申请人提供)：Charcot-Leyden晶体(CLC)蛋白， 形成独特的双锥体晶体，被视为嗜酸性粒细胞的标志 参与炎症反应，最初被确定为 嗜酸性粒细胞溶血磷脂酶(LPLase)。然而，我们已经表明，《中图法》不是 嗜酸性粒细胞LPLase，更确切地说，它属于动物的Galectin超家族 基于氨基酸序列、三维蛋白质结构、缺乏LPLase的凝集素 活性，以及其他人所表明的基因结构；它现在被指定为 Galectin-10。我们的X射线晶体结构显示CLC蛋白几乎是 与人类Galectin-1、-2、-3和-7相同，并具有碳水化合物 能够结合甘露糖的识别结构域(CRD)，但不是标准的 半乳糖苷一般被半乳糖素识别的糖类。我们最近展示了 嗜酸性粒细胞之一的S LPLase与75KD的胰腺LPLase相同，并且 CLC与该LPLase和另外两种蛋白质相互作用，这些蛋白质也可以 被抗LPLase抗体识别。基于这一发现，以及我们之前的 CLC蛋白编码基因在COS细胞中的表达 比对照细胞更高的LPLase活性，我们建议检验这一假设 CLC蛋白与LPLase相互作用，激活或稳定LPLase 人类嗜酸性粒细胞的活性。具体来说，我们建议：(1)界定 CLC蛋白--S糖结合蛋白的结构与功能关系 活性，(2)确定CLC蛋白的生物相关配基- 75KD的“胰腺”LPLase等，(3)研究LPLase的作用机制 ClC蛋白与75kD LPLase等配体的相互作用(S)，以及(4) 研究CLC蛋白和LPLase的细胞内功能相互作用(S 关于活体内。

DESCRIPTION (provided by applicant):Charcot-Leyden Crystal (CLC)protein, which forms the distinctive bipyramidal crystals seen as a hallmark of eosinophil participation in inflammatory reactions, was originally identified as eosinophil lysophospholipase (LPLase). However, we have shown that CLC is not eosinophil LPLase, rather, it belongs to the galectin super family of animal lectins based on amino acid sequence, 3D protein structure, lack of LPLase activity, and as shown by others, gene structure; it is now designated as galectin-10. Our X-ray crystal structure showed CLC protein to be nearly identical to human galectin- 1, -2, -3 and -7, and to possess a carbohydrate recognition domain (CRD) capable of binding mannose, but not standard Beta-galactoside sugars generally recognized by galectins. We recently showed that one of the eosinophil?s LPLases is identical to the 75KD pancreatic LPLase, and CLC interacts with this LPLase and two other proteins that can also be recognized by anti-LPLase antibodies. Based on this finding, and our prior report that COS cells transfected with the cDNA encoding CLC protein exhibited higher LPLase activity than control cells, we propose to test the hypothesis that CLC protein interacts with LPLases and activates or stabilizes LPLase activity in human eosinophils. Specifically, we propose: (1) to define structure-function relationships for CLC protein?s carbohydrate-binding activities, (2) to identify biologically relevant ligands for CLC protein - the 75KD "pancreatic" LPLase and others, (3) to characterize the mechanisms of interaction of CLC protein with the 75 KD LPLase and other ligand(s), and (4) to study the functional intracellular interactions of CLC protein and LPLase(s about in vivo.