Data from: Down syndrome cell adhesion molecule 1: testing for a role in insect immunity, behaviour and reproduction

Down syndrome cell adhesion molecule 1 (Dscam1) has wide-reaching and vital neuronal functions although the role it plays in insect and crustacean immunity is less well understood. In this study, we combine different approaches to understand the roles that Dscam1 plays in fitness-related contexts in two model insect species. Contrary to our expectations, we found no short-term modulation of Dscam1 gene expression after haemocoelic or oral bacterial exposure in Tribolium castaneum, or after haemocoelic bacterial exposure in Drosophila melanogaster. Furthermore, RNAi-mediated Dscam1 knockdown and subsequent bacterial exposure did not reduce T. castaneum survival. However, Dscam1 knockdown in larvae resulted in adult locomotion defects, as well as dramatically reduced fecundity in males and females. We suggest that Dscam1 does not always play a straightforward role in immunity, but strongly influences behaviour and fecundity. This study takes a step towards understanding more about the role of this intriguing gene from different phenotypic perspectives.

唐氏综合征细胞黏附分子1（Down syndrome cell adhesion molecule 1，Dscam1）虽在昆虫与甲壳动物免疫中的功能尚不完全明晰，却具备广泛且至关重要的神经元功能。本研究结合多种实验手段，旨在探究Dscam1在两种模式昆虫物种的适合度相关情境中所发挥的作用。与预期相悖的是，我们在赤拟谷盗（Tribolium castaneum）经血腔或经口细菌暴露后，以及黑腹果蝇（Drosophila melanogaster）经血腔细菌暴露后，均未检测到Dscam1基因表达的短期调控变化。此外，通过RNA干扰（RNA interference，RNAi）介导的Dscam1基因敲低联合后续细菌暴露实验，并未降低赤拟谷盗的存活率。但幼虫阶段的Dscam1基因敲低会导致成虫出现运动缺陷，同时显著降低雌雄个体的繁殖力。我们据此提出，Dscam1并非仅在免疫反应中发挥简单直接的作用，而是对昆虫行为与繁殖力具有强烈的调控影响。本研究从多表型视角出发，为进一步解析这一引人关注的基因的功能迈出了重要一步。