在大脑发育期间的De Novo和Salvage纯素合成的时空调节
Tomoya Mizukoshi1, Seiya Yamada2, Shin-Ichi Sakakibara2
1Laboratory for Molecular Neurobiology, Faculty of Human Sciences, Waseda University, Tokorozawa, Saitama 359-1192, Japan.
eNeuro
|September 28, 2023
概括
大脑发育依赖于纯氨酸合成途径. 这项研究揭示了从胚胎阶段的de novo途径转移到成年大脑的救援途径,影响神经干细胞增殖和mTORC1信号传递.
科学领域:
- 神经科学是一个神经科学.
- 发展生物学 发展生物学
- 生物化学 生化学
背景情况:
- 纯氨酸对于真核细胞平衡至关重要,由de novo和救援合成途径调节.
- 新生途径对于胚胎中枢神经系统 (CNS) 中的神经干细胞/原生细胞 (NSPC) 增殖至关重要.
- 我们对这些通路在中枢神经系统发育过程中的平衡和独特作用的理解是有限的.
研究的目的:
- 为了研究在中枢神经系统发育过程中氨酸合成途径的动态利用.
- 确定NSPCs在不同大脑区域和发育阶段的特定纯素通路要求.
- 阐明 purin 合成抑制对大脑发育和相关信号通路的影响.
主要方法:
- 在体外药理上抑制氨酸合成途径.
- 在NSPC中分析 purin合成酶表达特征.
- 在体内给小鼠模型注射新型 purin 合成抑制剂.
- 对大脑发育的组织学分析和mTORC1信号通路激活的评估.
主要成果:
- 观察到 purin 途径利用的动态转变: de novo 途径在胚胎阶段占主导地位,而救援途径在产后成人大脑中更为突出.
- 胚胎大脑NSPC主要使用de novo途径,而小脑NSPC需要两条途径.
- 在体内抑制de novo途径导致严重的前脑皮质低成形,这表明尿素需求的前后梯度.
- 新皮质的组织学缺陷与mTORC1/S6K/S6信号级联的下调相关.
结论:
- 时空调节de novo和救援 purin合成途径对于正确的大脑发育至关重要.
- purin 路径的动态影响NSPC的增殖,并且与mTORC1信号密切相关.
- 这些发现突出了发育中的大脑中素需求的区域差异.
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