相关实验视频
Updated: Feb 2, 2026
09:47
Spotting Cheetahs: Identifying Individuals by Their Footprints
Published on: May 1, 2016
15.3K
甲基甲因作为真核生物N端规则通路的N-degron
Jeong-Mok Kim1, Ok-Hee Seok1, Shinyeong Ju2,3
1Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea.
Science (New York, N.Y.)
|November 10, 2018
概括
酵母细胞核糖体可以在蛋白质上形成N-终端甲 (Nt-fMet),此前认为这种蛋白质只存在于细菌中. 这一由Gcn2激酶调节的过程通过fMet/N-degron途径对蛋白质进行降解.
科学领域:
- 分子和细胞生物学
- 蛋白质降解途径
- 翻译后的修改
背景情况:
- 细菌蛋白通常以已知的降解信号 (fMet/N-degron) 的N终端甲基甲 (Nt-fMet) 开始.
- 据推测,真核细胞蛋白与非形式化 metionin一起启动翻译.
研究的目的:
- 调查真核细胞质中N端蛋白形成的存在和调节.
- 确定参与真核Nt-fMet形成和降解的分子机制和信号通路.
主要方法:
- 酵母遗传学和分子生物学技术.
- 在各种压力条件下分析蛋白质形成水平.
- 激酶测定和蛋白质局部化研究.
- 标识和功能测试.
主要成果:
- 发现酵母甲基转移酶Fmt1,通常是线粒体,在细胞质中产生Nt-甲基化蛋白质.
- 在静止阶段和氨基酸饥饿期间,Nt型蛋白显著增加.
- Gcn2激酶的激活对于Fmt1细胞凝聚和Nt-形成的上调至关重要.
- 在酵母中,N-fMet残留物作为fMet/N-degron起作用.
- 鉴定出Psh1泛基因酶是细胞fMet/N-end规则路径的关键组成部分,该路径针对Nt-formylated蛋白进行破坏.
结论:
- 在真核细胞中存在N端蛋白形成,并通过应激反应途径进行调节.
- 在真核生物中,fMet/N-degron通路被保留,使用Nt-fMet作为降解信号.
- 这种新发现的真核蛋白质质量控制机制的关键组成部分是 Gcn2 激酶和 Psh1 基因酶.
相关概念视频
02:31Replication in Eukaryotes
204.8K
Overview
204.8K
02:40The Eukaryotic Promoter Region
18.8K
The eukaryotic promoter region is a segment of DNA located upstream of a gene. It contains an RNA polymerase binding site, a transcription start site, and several cis-regulatory sequences. The proximal promoter region is located in the vicinity of the gene and has cis-regulatory sequences and the core promoter. The core promoter is the binding site for RNA polymerase and is usually located between -35 and +35 nucleotides from the transcription start site. The distal promoter regions are...
18.8K
02:55Exceptions to the Octet Rule
37.6K
Many covalent molecules have central atoms that do not have eight electrons in their Lewis structures. These molecules fall into three categories:
37.6K
00:58Eukaryotic RNA Polymerases
27.1K
RNA Polymerase (RNAP) is conserved in all animals, with bacterial, archaeal, and eukaryotic RNAPs sharing significant sequence, structural, and functional similarities. Among the three eukaryotic RNAPs, RNA Polymerase II is most similar to bacterial RNAP in terms of both structural organization and folding topologies of the enzyme subunits. However, these similarities are not reflected in their mechanism of action.
All three eukaryotic RNAPs require specific transcription factors, of which the...
All three eukaryotic RNAPs require specific transcription factors, of which the...
27.1K
02:36Lewis Symbols and the Octet Rule
80.9K
Chemical bonds are complex interactions between two or more atoms or ions, which reduce the potential energy of the molecule. Gilbert N. Lewis developed a model called the Lewis model that simplified the depiction of chemical bond formation and provided straightforward explanations for the chemical bonds seen in most common compounds.
80.9K
03:02The Aufbau Principle and Hund's Rule
72.8K
To determine the electron configuration for any particular atom, we can build the structures in the order of atomic numbers. Beginning with hydrogen, and continuing across the periods of the periodic table, we add one proton at a time to the nucleus and one electron to the proper subshell until we have described the electron configurations of all the elements. This procedure is called the aufbau principle, from the German word aufbau (“to build up”). Each added electron occupies the...
72.8K