6月1日，《美國(guó)科學(xué)院院刊》（PNAS）發(fā)表了中國(guó)科學(xué)院上海生命科學(xué)研究院神經(jīng)科學(xué)研究所王佐仁研究組的最新研究成果─“Functional feedback from mushroom bodies to antennal lobes in the Drosophila olfactory pathway”,。這項(xiàng)工作主要由博士后胡愛(ài)群和研究生張偉在王佐仁研究員的指導(dǎo)下共同完成。
信息反饋在感覺(jué)處理中起著重要的作用。在昆蟲(chóng)中,，蘑菇體結(jié)構(gòu)被認(rèn)為介導(dǎo)嗅覺(jué)的學(xué)習(xí)與記憶及多感覺(jué)的整合,。Menzel實(shí)驗(yàn)室的鈷標(biāo)記研究提示：蜜蜂的蘑菇體與觸角葉之間可能存在反饋環(huán)路。作者利用遺傳學(xué)方法將外源P2X2受體特異表達(dá)在果蠅的蘑菇體從而研究果蠅的蘑菇體至觸角葉的反饋,。蘑菇體的激活以乙酰膽堿受體依賴(lài)的方式誘發(fā)了觸角葉的投射神經(jīng)元和局部中間神經(jīng)元的去極化改變,。蘑菇體神經(jīng)元βγ-軸突的激活與胞體的激活相比，引起了更強(qiáng)的觸角葉神經(jīng)元的去極化改變,。這些結(jié)果表明：果蠅蘑菇體與觸角葉之間存在功能反饋,，這種反饋很可能是經(jīng)βγ-軸突介導(dǎo)的。果蠅蘑菇體至觸角葉的功能性反饋提示果蠅嗅覺(jué)信息處理存在著自上而下的調(diào)節(jié),。
該工作得到了科技部973項(xiàng)目,、國(guó)家自然科學(xué)基金、中科院百人計(jì)劃和知識(shí)創(chuàng)新項(xiàng)目的支持,，以及中國(guó)博士后基金,、上海博士后基金的資助。(生物谷Bioon.com)
生物谷推薦原文出處：
PNAS doi: 10.1073/pnas.0914912107
Functional feedback from mushroom bodies to antennal lobes in the Drosophila olfactory pathway
Aiqun Hua,1, Wei Zhanga,b,1, and Zuoren Wanga,2
Feedback plays important roles in sensory processing. Mushroom bodies are believed to be involved in olfactory learning/memory and multisensory integration in insects. Previous cobalt-labeling studies have suggested the existence of feedback from the mushroom bodies to the antennal lobes in the honey bee. In this study, the existence of functional feedback from Drosophila mushroom bodies to the antennal lobes was investigated through ectopic expression of the ATP receptor P2X2 in the Kenyon cells of mushroom bodies. Activation of Kenyon cells induced depolarization in projection neurons and local interneurons in the antennal lobes in a nicotinic receptor-dependent manner. Activation of Kenyon cell axons in the βγ-lobes in the mushroom body induced more potent responses in the antennal lobe neurons than activation of Kenyon cell somata. Our results indicate that functional feedback from Kenyon cells to projection neurons and local interneurons is present in Drosophila and is likely mediated by the βγ-lobes. The presence of this functional feedback from the mushroom bodies to the antennal lobes suggests top-down modulation of olfactory information processing in Drosophila.
