PDF(Pubmed)
Abstract：
The brain regulates multiple physiological processes in fish. Despite this, knowledge about the basic structure and function of distinct brain regions in non-model fish species remains limited due to their diversity and the scarcity of common biomarkers. In the present study, four major brain parts, the telencephalon, diencephalon, mesencephalon and rhombencephalon, were isolated in largemouth bass, Micropterus salmoides. Within these parts, nine brain regions and 74 nuclei were further identified through morphological and cytoarchitectonic analysis. Transcriptome analysis revealed a total of 7153 region-highly expressed genes and 176 region-specifically expressed genes. Genes related to growth, reproduction, emotion, learning, and memory were significantly overexpressed in the olfactory bulb and telencephalon (OBT). Feeding and stress-related genes were in the hypothalamus (Hy). Visual system-related genes were predominantly enriched in the optic tectum (OT), while vision and hearing-related genes were widely expressed in the cerebellum (Ce) region. Sensory input and motor output-related genes were in the medulla oblongata (Mo). Osmoregulation, stress response, sleep/wake cycles, and reproduction-related genes were highly expressed in the remaining brain (RB). Three candidate marker genes were further identified for each brain regions, such as neuropeptide FF (npff) for OBT, pro-melanin-concentrating hormone (pmch) for Hy, vesicular inhibitory amino acid transporter (viaat) for OT, excitatory amino acid transporter 1 (eaat1) for Ce, peripherin (prph) for Mo, and isotocin neurophysin (itnp) for RB. Additionally, the distribution of seven neurotransmitter-type neurons and five types of non-neuronal cells across different brain regions were analyzed by examining the expression of their marker genes. Notably, marker genes for glutamatergic and GABAergic neurons showed the highest expression levels across all brain regions. Similarly, the marker gene for radial astrocytes exhibited high expression compared to other markers, while those for microglia were the least expressed. Overall, our results provide a comprehensive overview of the structural and functional characteristics of distinct brain regions in the largemouth bass, which offers a valuable resource for understanding the role of central nervous system in regulating physiological processes in teleost.
摘要：
大脑调节鱼类的多种生理过程。尽管如此,关于非模型鱼类不同大脑区域的基本结构和功能的知识仍然有限，因为它们的多样性和常见生物标志物的稀缺性。在本研究中,大脑的四个主要部分，端脑，间脑,中脑和菱形脑，被隔离在大嘴鲈鱼中，小昆虫。在这些部分中，通过形态学和细胞结构分析进一步鉴定了9个脑区和74个细胞核.转录组分析显示总共7153个区域高表达基因和176个区域特异性表达基因。与生长有关的基因，繁殖，情感，学习,和记忆在嗅球和端脑（OBT）中明显过表达。喂养和应激相关基因位于下丘脑(Hy)。视觉系统相关基因主要富集在视神经顶盖（OT），而视觉和听觉相关基因在小脑（Ce）区域广泛表达。与感觉输入和运动输出相关的基因位于延髓（Mo）中。宇宙调节,应激反应，睡眠/觉醒周期，与繁殖相关的基因在其余大脑（RB）中高表达。进一步确定了每个大脑区域的三个候选标记基因，如OBT的神经肽FF（NPFF），Hy的促黑色素浓缩激素（pmch），用于OT的囊泡抑制性氨基酸转运蛋白（viaat），Ce的兴奋性氨基酸转运蛋白1（eaat1），为Mo，和用于RB的isotocinneurophysin(itnp)。此外,通过检查标记基因的表达，分析了7种神经递质型神经元和5种非神经元细胞在不同脑区的分布。值得注意的是,谷氨酸能和GABA能神经元的标记基因在所有大脑区域显示出最高的表达水平。同样，与其他标记相比，放射状星形胶质细胞的标记基因表现出高表达，而小胶质细胞的表达最少。总的来说,我们的结果全面概述了大嘴鲈鱼不同大脑区域的结构和功能特征，这为理解中枢神经系统在调节硬骨鱼生理过程中的作用提供了宝贵的资源。
