将AKT1基形式输送到人体细胞中,揭示了差异性的基质选择性
Tarana Siddika1, Richard Shao1, Ilka U Heinemann1
1Department of Biochemistry, The University of Western Ontario, London, Ontario, Canada.
IUBMB life
|May 13, 2024
概括
具有特定酸化的工程蛋白激酶B (AKT1) 变体对细胞信号和增殖产生了差异性影响. 在Ser473的酸化对一些下游效应至关重要,而Thr308的酸化推动了最快的细胞生长.
科学领域:
- 分子生物学分子生物学
- 细胞信号传递 细胞信号传递
- 生物化学 生物化学
背景情况:
- 蛋白激酶B (AKT1) 是细胞存活,增殖和新陈代谢的关键调节者.
- AKT1活性通过在Thr308和Ser473的酸化来控制,高酸化与癌症的不良结果有关.
- 之前的研究表明,化AKT1形式的基质选择性差异.
研究的目的:
- 通过细胞透性TAT标记AKT1变异来研究人类细胞中的AKT1依赖活性.
- 在特定的调节部位 (Thr308,Ser473) 用编程酸化来设计AKT1,使用遗传密码扩展.
- 确定特定AKT1酸化状态对下游信号传导和细胞增殖的差异性影响.
主要方法:
- 利用酶工程和基因代码扩展与素-tRNA合成酶/tRNA对来创建TAT标记的AKT1变体.
- 工程变体包括非化AKT1,单化AKT1 (pAKT1T308, pAKT1S473),以及双化AKT1 (pAKT1T308,S473).
- 评估了HEK 293T细胞中的细胞传递,下游信号传递 (GSK-3α,GSK-3β,S6酸化) 和细胞增殖.
主要成果:
- 所有标记TAT的AKT1变种都被有效地传递到HEK 293T细胞中.
- 只有化AKT1变体刺激了下游信号,包括GSK-3α和S6化.
- 在S473 (TAT-pAKT1S473或TAT-pAKT1T308,S473) 的酸化增加了-GSK-3β水平.
- 虽然所有TAT-pAKT1变体都促进了增殖,但TAT-pAKT1T308表现出明显更快的细胞生长.
结论:
- 证明了AKT1形体在调节细胞过程中的差异性活性.
- 在AKT1上,特定的酸化部位在下游信号通路激活中起着不同的作用.
- 这些发现强调了精确AKT1酸化在调节细胞增殖中的重要性,并表明了潜在的治疗含义.
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