在肺腺癌中,PSAT1通过防止Rag异构体的形成来抑制mTORC1的激活
Yuhan Liu1,2,3,4,5, Zhujun Cheng6, Jinjin Zhang7
1Department of Thoracic Surgery, The First Affiliated Hospital of Nanchang University, Nanchang, China.
Autophagy
|July 24, 2025
概括
氨酸转移酶1 (PSAT1) 通过调节mTORC1信号传递,影响肺腺癌 (LUAD) 细胞增殖. 这项研究揭示了PSAT1.
科学领域:
- 细胞生物学 细胞生物学
- 代谢调节 代谢调节 代谢调节
- 癌症研究 癌症研究
背景情况:
- 拉巴胺复合体1 (mTORC1) 的机械标集成营养信号,特别是氨基酸,以控制细胞代谢和癌症进展.
- 氨酸转移酶1 (PSAT1),氨酸合成中的关键酶,在癌症中经常过度表达,通常促进瘤发生.
- 以前的研究表明,PSAT1倒置抑制了癌细胞的增殖和迁移,但其在肺腺癌 (LUAD) 中的作用呈现了复杂的情景.
研究的目的:
- 调查PSAT1在肺腺癌 (LUAD) 增殖中的看似矛盾的作用,其中过度表达和淘汰都促进了细胞生长.
- 阐明PSAT1影响LUAD细胞增殖和mTORC1信号传递的潜在分子机制.
- 在LUAD的背景下探索PSAT1,Rag GTPases和mTORC1定位之间的相互作用.
主要方法:
- 使用生物化学测试研究了PSAT1和RagB GTPases之间的相互作用.
- 评估了PSAT1调制 (过度表达和淘汰) 对mTORC1局部化到 lysosomes的影响.
- 量化自水平 (宏自/自) 和蛋白质合成速率作为对PSAT1变化的反应.
- 在PSAT1淘汰赛后分析了血清载体的表达,例如溶解物载体家族1成员5 (SLC1A5).
主要成果:
- 矛盾的是,PSAT1过度表达或淘汰会促进LUAD细胞的增殖,这与已知的癌症生物学相反.
- PSAT1优先结合GTP载荷的RagB,阻碍Rag异构体的形成,随后限制mTORC1的溶解体局部化.
- 这种PSAT1介导的mTORC1局部抑制增强了基底自,促进了LUAD细胞的增殖.
- PSAT1的淘汰导致Rag异构体的形成,mTORC1的激活,蛋白质合成的增加,以及血清载体SLC1A5.5的补偿上调.
结论:
- 这项研究揭示了PSAT1在控制LUAD细胞内的mTORC1信号通路方面的新型调节作用.
- PSAT1与Rag GTPases的相互作用调节mTORC1的局部化和自,影响LUAD细胞的增殖.
- 这些发现挑战了关于PSAT1功能的传统观点,并突出了其在LUAD病变发生过程中的复杂参与.
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