Department of Entomology, University of California-Davis, 1 Shields Ave, Davis, CA 95616, USA.
J Chem Ecol. 2010 Jul;36(7):787-94. doi: 10.1007/s10886-010-9811-5. Epub 2010 Jun 10.
General odorant-binding proteins (GOBPs) of moths are postulated to be involved in the reception of semiochemicals other than sex pheromones, the so-called "general odorants." We have expressed two GOBPs, AtraGOBP1 and AtraGOBP2, which were previously isolated from the antennae of the navel orangeworm, Amyelois transitella. Surprisingly, these two proteins did not bind compounds that are known to attract adult moths, particularly females. The proper folding and functionality of the recombinant proteins was inferred from circular dichroism analysis and demonstration that both GOBPs bound nonanal in a pH-dependent manner. EAG experiments demonstrated that female attractants (1-phenylethanol, propionic acid phenyl ester, and isobutyric acid phenyl ester) are detected with high sensitivity by the antennae of day-0 to day-4 adult females, with response declining in older moths. The same age-dependence was shown for male antennae responding to constituents of the sex pheromone. Interestingly, AtraGOBP2 bound the major constituent of the sex pheromone, Z11Z13-16Ald, with affinity comparable to that shown by a pheromone-binding protein, AtraPBP1. The related alcohol bound to AtraPBP1 with higher affinity than to AtraGOBP2. AtraGOBP1 bound both ligands with low but nearly the same affinity.
昆虫的一般气味结合蛋白（GOBP）被认为参与接收除性信息素以外的信息素，即所谓的“一般气味”。我们表达了两种 GOBP，AtraGOBP1 和 AtraGOBP2，它们之前是从 navel orangeworm（Amyelois transitella）的触角中分离出来的。令人惊讶的是，这两种蛋白不与已知吸引成年飞蛾，尤其是雌性的化合物结合。从圆二色性分析和证明这两种 GOBP 以 pH 依赖性方式结合壬醛推断出重组蛋白的正确折叠和功能。EAG 实验表明，雌性引诱剂（1-苯乙醇、丙酸苯酯和异丁酸苯酯）被日龄 0 至 4 天的成年雌性触角以高灵敏度检测到，随着时间的推移，老年飞蛾的反应会下降。雄性触角对性信息素成分的反应也表现出相同的年龄依赖性。有趣的是，AtraGOBP2 与性信息素的主要成分 Z11Z13-16Ald 结合具有亲和力，与性信息素结合蛋白 AtraPBP1 相当。相关醇与 AtraPBP1 的结合亲和力高于与 AtraGOBP2。AtraGOBP1 以低亲和力但几乎相同的亲和力结合两种配体。
