Xu Pingxi, Atkinson Rachel, Jones David N M, Smith Dean P
Department of Pharmacology, Center for Basic Neuroscience, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75335, USA.
Neuron. 2005 Jan 20;45(2):193-200. doi: 10.1016/j.neuron.2004.12.031.
Odorant binding proteins (OBPs) are extracellular proteins localized to the chemosensory systems of most terrestrial species. OBPs are expressed by nonneuronal cells and secreted into the fluid bathing olfactory neuron dendrites. Several members have been shown to interact directly with odorants, but the significance of this is not clear. We show that the Drosophila OBP lush is completely devoid of evoked activity to the pheromone 11-cis vaccenyl acetate (VA), revealing that this binding protein is absolutely required for activation of pheromone-sensitive chemosensory neurons. lush mutants are also defective for pheromone-evoked behavior. Importantly, we identify a genetic interaction between lush and spontaneous activity in VA-sensitive neurons in the absence of pheromone. The defects in spontaneous activity and VA sensitivity are reversed by germline transformation with a lush transgene or by introducing recombinant LUSH protein into mutant sensilla. These studies directly link pheromone-induced behavior with OBP-dependent activation of a subset of olfactory neurons.
气味结合蛋白（OBP）是一类细胞外蛋白，存在于大多数陆生生物的化学感受系统中。OBP由非神经元细胞表达，并分泌到包围嗅觉神经元树突的液体中。已证实几个成员可直接与气味剂相互作用，但其意义尚不清楚。我们发现果蝇的OBP lush对信息素11-顺式乙酸vaccenyl酯（VA）完全没有诱发活性，这表明这种结合蛋白是激活信息素敏感化学感受神经元所绝对必需的。lush突变体在信息素诱发行为方面也存在缺陷。重要的是，我们在没有信息素的情况下，确定了lush与VA敏感神经元自发活动之间的遗传相互作用。通过用lush转基因进行种系转化或向突变的感觉器中引入重组LUSH蛋白，自发活动和VA敏感性的缺陷得以逆转。这些研究直接将信息素诱导的行为与OBP依赖的一部分嗅觉神经元的激活联系起来。
