State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China.
Biological Science Research Center, Southwest University, Chongqing, China.
Insect Mol Biol. 2023 Jun;32(3):251-262. doi: 10.1111/imb.12828. Epub 2023 Jan 27.
Animal behaviour regulation is a complex process involving many factors, and the nervous system is an essential factor in this process. In many species, pathogens can alter host behaviour by affecting the host's nervous system. An interesting example is that the silkworm shows enhanced locomotor behaviour after being infected with the nucleopolyhedrosis virus. In this study, we analysed the transcriptome of the silkworm brain at different time points after infection and found that various genes related to behaviour regulation changed after infection. In-depth analysis showed that the tyrosine hydroxylase gene might be a key candidate gene, and the content of dopamine, its downstream metabolite, increased significantly in the brain of silkworms infected with the virus. After the injection of tyrosine hydroxylase inhibitor into the infected silkworm, the dopamine content in the silkworm brain decreased and the locomotor behaviour caused by the virus was blocked successfully. These results confirm that tyrosine hydroxylase is involved in regulating enhanced locomotor behaviour after virus infection in silkworms. Furthermore, the tyrosine hydroxylase gene was specifically overexpressed in the brain of the silkworm, and the transgenic silkworm was enhanced in locomotor behaviour and foraging behaviour. These results suggest that the tyrosine hydroxylase gene plays a vital role in regulating insect behaviour.
动物行为调节是一个涉及许多因素的复杂过程，而神经系统是这个过程中的一个重要因素。在许多物种中，病原体可以通过影响宿主的神经系统来改变宿主的行为。一个有趣的例子是，家蚕感染核型多角体病毒后表现出增强的运动行为。在这项研究中，我们分析了感染后不同时间点家蚕大脑的转录组，发现感染后与行为调节相关的各种基因发生了变化。深入分析表明，酪氨酸羟化酶基因可能是一个关键候选基因，病毒感染后家蚕脑中多巴胺的含量及其下游代谢物明显增加。向感染的家蚕体内注射酪氨酸羟化酶抑制剂后，家蚕脑中的多巴胺含量下降，病毒引起的运动行为被成功阻断。这些结果证实了酪氨酸羟化酶在家蚕感染病毒后调节增强运动行为的作用。此外，在家蚕的大脑中特异性过表达了酪氨酸羟化酶基因，转基因家蚕在运动行为和觅食行为方面得到增强。这些结果表明，酪氨酸羟化酶基因在家蚕行为调节中起着至关重要的作用。
