作为对营养补充的反应,脂质组的重塑需要酵母酵母中的tRNA修饰剂Deg1/Pus3
Gabriel Soares Matos1, Leonie Vogt2, Rosangela Silva Santos3
1Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
Molecular microbiology
|October 21, 2023
概括
酵母中Pus3/Deg1的缺失通过改变特定的误读错误来增加脂质滴,从而影响独立于Snf1/AMPK激酶的中性脂质合成. 这会影响无菌水平和脂质平衡.
科学领域:
- 分子生物学分子生物学
- 酵母遗传学 酵母遗传学
- 脂质代谢 脂质代谢是什么
背景情况:
- 伪尿素合成酶Pus3/Deg1修改了tRNA,而它在Saccharomyces cerevisiae中缺少导致脂质滴 (LD) 含量增加,转化缺陷和蛋白质聚合.
- 这种 deg1 突变体表现出类似饥饿的转录组变化和特定的误读错误,可能会影响关键的脂质合成调节剂,如乙-CoA 碳氧化酶 (Acc1) 和 Snf1/AMPK 激酶.
研究的目的:
- 调查 deg1 突变调高酵母中中性脂质含量的机制.
- 为了确定观察到的脂质变化是否由Snf1/AMPK激酶途径介导.
- 阐明受 deg1 突变影响的特定脂类物种及其在脂质恒温中的作用.
主要方法:
- 在野生型和 deg1 突变酵母菌株中对脂质滴滴含量的比较分析.
- 对乙烯基-CoA碳酸酶 (Acc1) 调节和酸化状态的研究.
- 野生类型和deG1突变体的综合性脂质组学分析,以确定改变的脂质物种.
- 从储存脂质中评估乙-CoA调动能力.
主要成果:
- 降解1突变通过与Snf1/AMPK激酶依赖的Acc1调节相对应的机制来调节中性脂质含量.
- 脱基1突变特别调高了无菌 (SE) 水平,与影响Acc1调节酸化位点 (Ser-1157) 的突变不同,这种突变主要影响三糖醇 (TG).
- 脂质组分析揭示了 deg1 突变体中多种改变的脂质物种,包括在指数增长期间的脂减少,表明乙基-CoA 调动受损.
结论:
- Deg1在协调脂质储存和调动方面发挥着至关重要的作用,从而影响酵母体的整体脂质平衡.
- 在Deg1突变体中观察到的脂质学变化可能间接地是由蛋白质聚合引发的应激反应引起的.
- 这些发现突显出一种新的脂质代谢调节途径,受tRNA修饰和蛋白质平衡的影响.
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