雄性和雌性行為之間的先天差別一定是寫(xiě)在他們各自基因組中的，但這些差別是怎樣編碼截然不同的神經(jīng)通道的在很大程度上仍然不清楚,。通過(guò)專注于對(duì)果蠅cVA信息素的性別特異反應(yīng),，Richard Axel及其同事現(xiàn)在識(shí)別出了由將嗅覺(jué)信號(hào)攜帶到運(yùn)動(dòng)中樞的四個(gè)連續(xù)神經(jīng)元所組成的一個(gè)鏈條，其中雄性-雌性之間的所有解剖差別都在一個(gè)保守的感覺(jué)細(xì)胞的下游,。由這個(gè)研究小組建立的方法應(yīng)能幫助其他研究小組進(jìn)行神經(jīng)回路定位——這項(xiàng)工作即便是對(duì)相對(duì)簡(jiǎn)單的果蠅大腦來(lái)說(shuō)也仍然是令人望而生畏的,。（生物谷Bioon.com）
生物谷推薦原文出處：
Nature doi:10.1038/nature09554
A dimorphic pheromone circuit in Drosophila from sensory input to descending output
Vanessa Ruta,Sandeep Robert Datta,Maria Luisa Vasconcelos,Jessica Freeland,Loren L. Looger& Richard Axel
Drosophila show innate olfactory-driven behaviours that are observed in naive animals without previous learning or experience, suggesting that the neural circuits that mediate these behaviours are genetically programmed. Despite the numerical simplicity of the fly nervous system, features of the anatomical organization of the fly brain often confound the delineation of these circuits. Here we identify a neural circuit responsive to cVA, a pheromone that elicits sexually dimorphic behaviours1, 2, 3, 4. We have combined neural tracing using an improved photoactivatable green fluorescent protein (PA-GFP) with electrophysiology, optical imaging and laser-mediated microlesioning to map this circuit from the activation of sensory neurons in the antennae to the excitation of descending neurons in the ventral nerve cord. This circuit is concise and minimally comprises four neurons, connected by three synapses. Three of these neurons are overtly dimorphic and identify a male-specific neuropil that integrates inputs from multiple sensory systems and sends outputs to the ventral nerve cord. This neural pathway suggests a means by which a single pheromone can elicit different behaviours in the two sexes.
