人类单半氨酸合成酶,SEPSECS,已经演变为优化基于tRNA的基质的结合
Anupama K Puppala1, Dylan Sosa2, Jennifer Castillo Suchkou1
1Department of Biochemistry and Molecular Genetics, University of Illinois at Chicago, Chicago, IL 60607, USA.
Nucleic acids research
|October 10, 2024
概括
这是一种O-phosphoseryl-tRNASec转移酶 (SepSecS) 酶.
科学领域:
- 生物化学 生物化学
- 分子生物学分子生物学
- 进化生物学 进化生物学
背景情况:
- 结合单半氨酸 (Sec) 对于所有生命领域的单蛋白质组发育至关重要.
- O-phosphoseryl-tRNASec转移酶 (SepSecS) 是古生物和真核生物中Sec合成的关键.
- 人类SEPSECS表现出不对称的tRNA结合,C端螺旋体影响复杂的稳定性.
研究的目的:
- 研究SEPSECStRNA结合机制的进化起源.
- 确定C终端扩展在SEPSECS功能和监管中的作用.
- 了解哺乳动物和古人类SEPSECS之间的tRNA结合的差异.
主要方法:
- 在不同物种中对SEPSECS进行比较结构分析.
- 遗传学分析,以追踪tRNA结合基因的演变.
- 生物化学测试以评估tRNA结合 afinities 和要求.
主要成果:
- SEPSECS tRNA结合动机在物种中保存不良.
- 考古SEPSECS需要一个氨基酸组来结合tRNA,与哺乳动物SEPSECS不同.
- C终端α-螺旋16是一种哺乳动物创新,可以防止低度tRNA的聚合.
结论:
- SEPSECS在不同领域的生命中演化出了不同的tRNA结合机制.
- 哺乳动物的C端螺旋体代表了SEPSECS功能的监管创新.
- 这些发现突显了SEPSECS作为单蛋白合成的监管点的演变.
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