近日，德国马克斯·普朗克化学生态学研究所Silke Sachse等研究人员合作揭示迁徙蝗虫触角叶的环形气味编码。相关论文于2024年6月18日在线发表于国际学术期刊《细胞》。

研究人员利用CRISPR-Cas9系统在嗅觉神经元中，产生表达基因编码的钙指示剂GCaMP的转基因蝗虫。利用双光子功能成像技术，研究人员绘制了代表所有六个发育阶段中各种生态相关气味的空间激活模式图。研究结果揭示了由特定团簇组成的触角叶环形功能组织。这种结构以小球环的形式编码不同的化学类别和生态学上不同的气味，从而建立了气味特异性化学表征。

研究人员通过选择性靶向表达OR70a的感觉神经元证实，这种环形小球排列发生在整个发育过程中，而且小球群内的气味编码模式在各个发育阶段都是一致的。从机理上讲，这种非传统的空间嗅觉编码反映了蝗虫特有的触角叶小球多重神经支配模式。

据了解，长期以来，气味在具有两千多个小球的蝗虫触角叶中的表现一直是一个令人困惑的难题。

附：英文原文

Title: Ring-shaped odor coding in the antennal lobe of migratory locusts

Author: Xingcong Jiang, Eleftherios Dimitriou, Veit Grabe, Ruo Sun, Hetan Chang, Yifu Zhang, Jonathan Gershenzon, Jürgen Rybak, Bill S. Hansson, Silke Sachse

Issue&Volume: 2024-06-18

Abstract: The representation of odors in the locust antennal lobe with its >2,000 glomeruli has long remained a perplexing puzzle. We employed the CRISPR-Cas9 system to generate transgenic locusts expressing the genetically encoded calcium indicator GCaMP in olfactory sensory neurons. Using two-photon functional imaging, we mapped the spatial activation patterns representing a wide range of ecologically relevant odors across all six developmental stages. Our findings reveal a functionally ring-shaped organization of the antennal lobe composed of specific glomerular clusters. This configuration establishes an odor-specific chemotopic representation by encoding different chemical classes and ecologically distinct odors in the form of glomerular rings. The ring-shaped glomerular arrangement, which we confirm by selective targeting of OR70a-expressing sensory neurons, occurs throughout development, and the odor-coding pattern within the glomerular population is consistent across developmental stages. Mechanistically, this unconventional spatial olfactory code reflects the locust-specific and multiplexed glomerular innervation pattern of the antennal lobe.

DOI: 10.1016/j.cell.2024.05.036

Source: https://www.cell.com/cell/fulltext/S0092-8674(24)00580-4