Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China.
Department of Entomology, College of Plant Protection, China Agricultural University, Yuanmingyuan Xilu 2, Haidian District, Beijing 100093, China.
J Insect Physiol. 2019 Oct;118:103933. doi: 10.1016/j.jinsphys.2019.103933. Epub 2019 Aug 23.
Migratory locusts (Locusta migratoria) frequently aggregate into huge swarms that cause serious economic losses for the agricultural sector. Differential behaviors of male and female insects may contribute to such population explosions. However, the key olfactory mechanisms underlying different behaviors associated with sex-related pheromones are unclear. Here, we report that male-specific odor, 2-heptanone plays different roles in relation to the behavior of migratory locust males and females, and that this sexual dimorphism involves a soluble odorant-binding protein (OBP) in the peripheral olfactory processes. This odor strongly binds to LmigOBP4, a novel OBP, present in antennal trichoid sensilla, and elicits opposite locomotor tendencies between the sexes: attracting females and repelling males. Furthermore, an adult male group mimicked a high dosage of 2-heptanone by promoting their attractiveness to single females. Additionally, RNAi suppression of Lmigobp4 expression reduced the physiological responses to 2-heptanone to levels that were indistinguishable between the sexes. This suppression reversed the adult behavioral responses to 2-heptanone, i.e., females were repelled and males were attracted. We conclude that LmigOBP4 is associated with olfactory recognition of male-specific 2-heptanone, which plays dual roles that differ between adult male and female migratory locusts.
迁徙蝗（Locusta migratoria）经常聚集成群，对农业部门造成严重经济损失。雌雄昆虫的不同行为可能导致这种种群爆发。然而，与性信息素相关的不同行为的关键嗅觉机制尚不清楚。在这里，我们报告说，雄性特有的气味 2-庚酮在与雄性和雌性迁徙蝗相关的行为中发挥不同的作用，这种性别二态性涉及到外周嗅觉过程中的一种可溶性气味结合蛋白（OBP）。这种气味强烈地与存在于触角毛状感器中的新型 OBP LmigOBP4 结合，并在两性之间引起相反的运动趋势：吸引雌性和排斥雄性。此外，成年雄性群体通过促进对单个雌性的吸引力来模拟高剂量的 2-庚酮。此外，Lmigobp4 表达的 RNAi 抑制降低了对 2-庚酮的生理反应，使两性之间的反应无法区分。这种抑制逆转了对 2-庚酮的成年行为反应，即雌性被排斥，雄性被吸引。我们得出结论，LmigOBP4 与雄性特有的 2-庚酮的嗅觉识别有关，它在成年雄性和雌性迁徙蝗之间发挥着不同的双重作用。
