中华蜜蜂视觉-嗅觉跨模态学习及其分子机理研究

The chinese honeybee, Apis cerana. cerana (A.c.c.) are a valuable natural resource of China, and have impressive abilities in visual and olfactory cognition. This study uses A.c.c. as main experimental materials for testing a visual-olfactory cross-model learning. The learning model is based on a proboscis extension reflex (PER) instrument combining color and odor. Subsequently, the RNA sequencing (RNA-Seq) and isobaric tags for relative and absolute quantitation (iTRAQ) will be employed to identify the genes, proteins and signal pathways that maybe involved in the visual–olfactory cross-modal learning, and then a network of protrein-protein interactions will be constructed. In addition, the targeted genes are obtained on the basis of correlation analysis of the identified genes and proteins, and their functions will be comfirmed by the RNA interference (RNAi) technology. This project aims to clarify the specific molecular mechanisms of the visual–olfactory cross-modal learning in A.c.c. and serves as a theoretical model for the cross-modal learning of other animals, but also have practical applications for the rearing and utilisation of A.c.c..

中蜂是我国宝贵的自然遗传资源，具有较强的视觉和嗅觉认知能力。本项目以中华蜜蜂为研究对象，建立基于PER的视觉-嗅觉跨模态学习记忆模型，对中华蜜蜂的跨模态学习进行研究。然后利用RNA-Seq和iTRAQ技术筛选出可能参与视觉-嗅觉跨模态学习的基因、蛋白、信号通路，并构建蛋白互作图。将筛选出的基因和蛋白联合分析，确定目标基因，进一步通过RNA干扰技术验证目标基因在中华蜜蜂视觉-嗅觉跨模态学习中的功能作用。本项目的研究旨在弄清中华蜜蜂视觉-嗅觉跨模态学习的分子基础，以期为动物跨模态认知的研究提供一个理论模型，更重要的是为保护和利用中华蜜蜂提供新思路。

特定基因或者编码蛋白通过一定的信号通路参与调控了不同物种的多种学习方式，双模态记忆形成过程中是否也存在特定基因的调控目前还是未知。采用多组学方法测试执行了三种不同学习任务蜜蜂大脑的基因或者蛋白的变化，双模态学习之后基因和蛋白有一个总的上调趋势。差异蛋白的互作图结合荧光原位杂交分析发现α-氨基己二酸半醛脱氢酶(ALDH7A1)可能参与了双模态学习记忆的调控。给蜜蜂大脑注射ALDH7A1-siRNA后直接抑制了ALDH7A1 and regucalcin 的表达，并且增加了一种神经递质β-丙氨酸的含量。有趣的是，在ALDH7A1基因干扰之后，我们发现ALDH7A的降低仅仅影响蜜蜂的视觉嗅觉双模态学习记忆，而不影响单视觉或者单嗅觉的学习。因此，我们推断ALDH7A1可能通过控制β-丙氨酸相关的可塑性机制影响双模态学习记忆。