从线粒体蛋白MiNT转移不对称的 [2Fe2S] 集群到受体
Yaqin Zhao1, Xiaoyan Liu1, Xinyao Ju1
1Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China.
International journal of biological macromolecules
|August 29, 2025
概括
这项研究揭示了 MiNT 蛋白中的两个 [2Fe2S] 集群的不同作用,影响铁稳态和细胞过程. 了解这些差异是解读序列保存的关键.
科学领域:
- 生物化学
- 分子生物学
- 细胞生物学
背景情况:
- 包括MiNT (Miner2) 在内的NEET蛋白对于调节铁和反应性氧物种 (ROS) 稳态至关重要.
- MiNT 含有两个 CDGSH 域,它们结合 [2Fe2S] 集群,对其功能至关重要.
研究的目的:
- 研究 MiNT 蛋白中的两个 [2Fe2S] 之间的功能异质性.
- 阐明每个 [2Fe2S] 集群对蛋白质构成和铁集群转移的差异性贡献.
主要方法:
- 将His75和His113残留物转化为Cys以区分两个 [2Fe2S] 集群.
- 光共振能量转移 (FRET) 系统的建设,以监测 [2Fe2S] 集群的转移.
- 对 [2Fe2S] 集群转移到受体蛋白的动态分析.
主要成果:
- 与 [2Fe2S]1相比,第二个CDGSH域中的 [2Fe2S]2集群的疏水性暴露较小.
- 确定了 [2Fe2S]1 (0.027 S-1) 和 [2Fe2S]2 (0.017 S-1) 到线粒体铁素 (Fdx) 的不同转移速度.
- 这项研究强调了两个[Fe2S]集群在MiNT功能中的不同作用.
结论:
- 在MiNT中的两个[Fe2S]集群具有影响蛋白质构成和铁转移动态的独特特性.
- 在细胞循环中利用铁的过程中,MiNT 能够调解差异化 [2Fe2S] 集群的转移.
- 这项研究提供了关于序列保护如何决定铁结合蛋白的特定生物功能的见解.
相关概念视频
Translocation of Proteins into the Mitochondria
3.2K
Mitochondrial precursors are translocated to the internal subcompartments via independent mechanisms involving distinct protein machineries called translocases.
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
3.2K
Electron Transport Chain: Complex I and II
15.0K
The mitochondrial electron transport chain (ETC) is the main energy generation system in the eukaryotic cells. However, mitochondria also produce cytotoxic reactive oxygen species (ROS) due to the large electron flow during oxidative phosphorylation. While Complex I is one of the primary sources of superoxide radicals, ROS production by Complex II is uncommon and may only be observed in cancer cells with mutated complexes.
ROS generation is regulated and maintained at moderate levels necessary...
ROS generation is regulated and maintained at moderate levels necessary...
15.0K
Electron Transport Chains
102.5K
The final stage of cellular respiration is oxidative phosphorylation that consists of two steps: the electron transport chain and chemiosmosis. The electron transport chain is a set of proteins found in the inner mitochondrial membrane in eukaryotic cells. Its primary function is to establish a proton gradient that can be used during chemiosmosis to produce ATP and generate electron carriers, such as NAD+ and FAD, that are used in glycolysis and the citric acid cycle.
The ETC is comprised of...
The ETC is comprised of...
102.5K
Mitochondrial Protein Sorting
4.4K
Mitochondria are double-membrane organelles of the eukaryotes involved in cellular metabolism, signaling, ATP synthesis, and programmed cell death. Each of these processes requires specific proteins and enzymes that must be correctly sorted to the right mitochondrial subcompartment for the proper functioning of the organelle.
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
Most of these mitochondrial proteins are encoded by the nucleus and imported to the mitochondria as unfolded or loosely folded precursors. Mitochondrial precursors...
4.4K
Protein Transport into the Inner Mitochondrial Membrane
4.1K
Nuclear encoded mitochondrial precursors are imported to the inner membrane in a multistep process involving two separate translocons, TIM22 and TIM23. TIM23 is a cation-selective pore that remains closed by the N terminal segment of the protein. Negative charges on the TIM23 act as a receptor for the incoming precursor, pulling the positively charged matrix-targeting sequence for peptide insertion and translocation.
Transport of mitochondrial precursors across the TIM23 channel is driven by...
Transport of mitochondrial precursors across the TIM23 channel is driven by...
4.1K
Energy to Drive Translocation
2.1K
Mitochondrial protein import is powered by two distinct energy sources: ATP hydrolysis and electrochemical potential across the inner membrane. Newly synthesized precursors are bound by cytosolic chaperones of the Hsp70 family, which guide them to the import receptors on the mitochondrial surface. Utilizing the energy of ATP hydrolysis, Hsp70 chaperones transfer these precursors to the TOM receptors on the mitochondrial outer membrane.
Generally, polypeptides are unfolded by two distinct...
Generally, polypeptides are unfolded by two distinct...
2.1K


