Purification, crystallization and preliminary X-ray crystallographic analysis of human IL-18 and its extracellular complexes
Purification, crystallization and preliminary X-ray crystallographic analysis of human IL-18 and its extracellular complexes
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DOI：
10.1107/s2053230x14016926
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发表时间：
2014-10-01
影响因子：
0.9
通讯作者：
Tochio, Hidehito
中科院分区：
文献类型：
--
作者：
Kimura, Takeshi;Tsutsumi, Naotaka;Tochio, Hidehito
白细胞介素-18 （IL-18）是一种促炎细胞因子，属于白细胞介素-1 （IL-1）家族，参与自身免疫/自身炎症和过敏性疾病的发病机制，如青少年特发性关节炎和支气管哮喘。IL-18与IL-18受体α (IL-18R α)和β (IL-18R β)链形成信号复合物；然而，具体的激活机制尚不清楚。本研究纯化和结晶了IL-18- il - 18r α二元和IL-18- il - 18r α - il - 18r β三元配合物以及IL-18。从空间群P2(1)晶体中采集了IL-18的x射线衍射数据集，分辨率为2.33埃，单胞参数为a = 68.15, b = 79.51, c = 73.46埃，β = 100.97度。IL-18二元配合物和三元配合物的晶体分别属于正交空间群P2(1)2(1)2和P2(1)2(1)2(1) 2(1))，衍射分辨率为3.10埃。二元配合物的单位胞参数为a = 135.49, b = 174.81, c = 183.40埃，三元配合物的单位胞参数为a = 72.56, b = 111.56, c = 134.57埃。
Interleukin-18 (IL-18), a pro-inflammatory cytokine belonging to the interleukin-1 (IL-1) family, is involved in the pathogenesis of autoimmune/autoinflammatory and allergic diseases such as juvenile idiopathic arthritis and bronchial asthma. IL-18 forms a signalling complex with the IL-18 receptor alpha (IL-18R alpha) and beta (IL-18R beta) chains; however, the detailed activation mechanism remains unclear. Here, the IL-18-IL-18R alpha binary and IL-18-IL-18R alpha-IL-18R beta ternary complexes were purified and crystallized as well as IL-18 alone. An X-ray diffraction data set for IL-18 was collected to 2.33 angstrom resolution from a crystal belonging to space group P2(1), with unit-cell parameters a = 68.15, b = 79.51, c = 73.46 angstrom, beta = 100.97 degrees. Crystals of both the IL-18 binary and ternary complexes belonging to the orthorhombic space groups P2(1)2(1)2 and P2(1)2(1)2(1), respectively, diffracted to 3.10 angstrom resolution. Unit-cell parameters were determined as a = 135.49, b = 174.81, c = 183.40 angstrom for the binary complex and a = 72.56, b = 111.56, c = 134.57 angstrom for the ternary complex.