Department of Anatomy, University of California San Francisco, San Francisco, CA, USA.
PLoS One. 2012;7(12):e51684. doi: 10.1371/journal.pone.0051684. Epub 2012 Dec 17.
Habituation is a form of non-associative learning that enables animals to reduce their reaction to repeated harmless stimuli. When exposed to ethanol vapor, Drosophila show an olfactory-mediated startle response characterized by a transient increase in locomotor activity. Upon repeated exposures, this olfactory startle attenuates with the characteristics of habituation. Here we describe the results of a genetic screen to identify olfactory startle habituation (OSH) mutants. One mutation is a transcript specific allele of foraging (for) encoding a cGMP-dependent kinase. We show this allele of for reduces expression of a for-T1 isoform expressed in the head and functions normally to inhibit OSH. We localize for-T1 function to a limited set of neurons that include olfactory receptor neurons (ORNs) and the mushroom body (MB). Overexpression of for-T1 in ORNs inhibits OSH, an effect also seen upon synaptic silencing of the ORNs; for-T1 may therefore function in ORNs to decrease synaptic release upon repeated exposure to ethanol vapor. Overall, this work contributes to our understanding of the genes and neurons underlying olfactory habituation in Drosophila.
习惯化是一种非联想学习形式，使动物能够减少对重复无害刺激的反应。当暴露于乙醇蒸气中时，果蝇表现出嗅觉介导的惊跳反应，其特征是运动活性的短暂增加。在重复暴露后，这种嗅觉惊跳反应会随着习惯化的特征而减弱。在这里，我们描述了一项遗传筛选的结果，以鉴定嗅觉惊跳习惯化（OSH）突变体。一个突变是觅食（for）的转录体特异等位基因，编码 cGMP 依赖性激酶。我们表明，该 for 等位基因减少了在头部表达的 for-T1 同工型的表达，并正常抑制 OSH。我们将 for-T1 功能定位到一组有限的神经元，包括嗅觉受体神经元（ORNs）和蘑菇体（MB）。在 ORNs 中过表达 for-T1 会抑制 OSH，这一效应也见于 ORNs 的突触沉默；因此，for-T1 可能在 ORNs 中起作用，在重复暴露于乙醇蒸气时减少突触释放。总的来说，这项工作有助于我们理解果蝇嗅觉习惯化的基因和神经元。
