category
bioRxiv
date
Mar 7, 2026
slug
status
Published
summary
揭示Nar1通过双界面(静电相互作用和靶向肽段识别)结合CIA靶向复合物的分子机制,提出铁硫簇转移的结构模型,阐明Nar1在铁硫蛋白成熟过程中的枢纽作用
tags
蛋白质组学
type
Post
📄 原文题目
Nar1 binds the cytosolic iron sulfur cluster assembly targeting complex via a bipartite interaction interface
🔗 原文链接
💡 AI 核心解读
揭示Nar1通过双界面(静电相互作用和靶向肽段识别)结合CIA靶向复合物的分子机制,提出铁硫簇转移的结构模型,阐明Nar1在铁硫蛋白成熟过程中的枢纽作用
📝 英文原版摘要
The cytosolic iron-sulfur cluster assembly (CIA) pathway maturates essential nuclear and cytosolic Fe-S proteins required for genome maintenance and cellular metabolism. Nar1 (also called CIAO3 or IOP1) is a conserved Fe-S protein that connects the early and late steps of the CIA pathway, yet the molecular basis for its proposed function as a metallocluster carrier remains poorly defined. In particular, the interactions responsible for Nar1 recruitment to the CIA targeting complex (CTC) during cluster delivery remain unknown. Here, we define the molecular basis for Nar1 recruitment to the CTC using biochemical reconstitution, quantitative protein-protein interaction assays, and AlphaFold modeling. Our data reveal that Nar1 binds the CTC through two distinct interfaces. A primary interface comprises an electrostatic interaction that anchors Nar1 to a conserved acidic surface on the Cia1 subunit of the CTC and a secondary interface involves binding of Nar1's divergent targeting complex recognition peptide at the Cia1-Cia2 interface. Thus, Nar1 engages a conserved CTC surface that serves as a recruitment platform for multiple binding partners, including CIA clients. Computational structural models position the putative Fe-S cluster donor site of Nar1 adjacent to a proposed acceptor site on Cia2, suggesting that this bipartite binding mechanism positions Nar1 for transfer of an Fe-S cluster to the targeting complex. Together, these findings resolve conflicting models for Nar1 recruitment and establish a mechanistic framework for understanding how the CTC engages multiple binding partners during cytosolic iron-sulfur protein maturation.
- 作者:NotionNext
- 链接:https://tangly1024.com/article/31d48bd6-1f96-813e-ae57-c80f86fa166b
- 声明:本文采用 CC BY-NC-SA 4.0 许可协议,转载请注明出处。
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