Binding properties of pheromone-binding protein 1 from the common cutworm Spodoptera litura
Binding properties of pheromone-binding protein 1 from the common cutworm Spodoptera litura
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斜纹夜蛾信息素结合蛋白 1 的结合特性
DOI：
10.1016/j.cbpb.2011.11.007
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发表时间：
2012-04-01
影响因子：
2.2
通讯作者：
Dong, Shuang-Lin
中科院分区：
文献类型：
--
作者：
Liu, Nai-Yong;He, Peng;Dong, Shuang-Lin
信息素结合蛋白（PBP）以前被认为是被动信息素载体。然而，最近的研究，特别是在果蝇中的研究表明，PBP 参与化学信息素的识别，从而使配体结合研究更有意义。此前，我们从斜纹夜蛾（Slit）中克隆了三个 PBP，并表明 SlitPBP1 比其他两个丰富得多，特别是在雄性触角中。为了研究 SlitPBP1 的配体特异性，我们在细菌系统中表达了该蛋白，并与特定性信息素的三种成分（Z9-14:Ac、Z9,E11-14:Ac 和 Z9,E12-14:Ac）以及 26 种挥发性配体进行了结合实验。结果表明，SlitPBP1 结合所有三种性信息素成分，解离常数在 0.6 至 1.1 μM 之间。相同的蛋白质还以相当的亲和力结合几种信息素类似物，但不结合植物挥发物。双键的存在是强结合的最重要因素，而其位置和构型也会影响亲和力。最后，信息素成分的结合受 pH 值的强烈影响，显示出与蛋白质等电点相对应的临界 pH 值。这表明 SlitPBP1 中可能存在 pH 依赖性构象机制，用于信息素的结合和释放。 (C) 2011 Elsevier Inc. 保留所有权利。
Pheromone-binding proteins (PBPs) were formerly thought to act as passive pheromone carriers. However, recent studies, particularly in Drosophila melanogaster, suggest that PBPs are involved in the recognition of semiochemicals, thus making ligand-binding studies more meaningful. Previously, we cloned three PBPs from Spodoptera litura (Slit), and showed that SlitPBP1 is much more abundant than the other two, particularly in male antennae. To investigate the ligand specificity of SlitPBP1, we expressed the protein in a bacterial system and performed binding experiments with the three components of the specific sex pheromones (Z9-14:Ac, Z9,E11-14:Ac and Z9,E12-14:Ac), as well as with 26 volatile ligands. The results indicated that SlitPBP1 bound all three sex pheromone components with dissociation constants between 0.6 and 1.1 mu M. The same protein also bound with comparable affinities several pheromone analogs, but not plant volatiles. The presence of a double bond was the most important element for a strong binding, while its position and configuration also affected the affinity. Finally, the binding of pheromone components is strongly affected by pH, showing a critical pH value corresponding to isoelectric point of the protein. This suggests that a pH-dependent conformational mechanism might exist in SlitPBP1 for pheromone binding and release. (C) 2011 Elsevier Inc. All rights reserved.