Single molecule imaging reveals the collective and independent search mechanisms of cFos and cJun on DNA
Single molecule imaging reveals the collective and independent search mechanisms of cFos and cJun on DNA
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单分子成像揭示了cFos和cJun在DNA上集体且独立的搜索机制
DOI：
10.1101/2020.01.24.918300
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Leech J
中科院分区：
文献类型：
--
作者：
Leech J
AP-1蛋白是碱性亮氨酸拉链(BZIP)二聚体转录因子家族的成员，它促进了多种细胞过程，但主要是因为它们在几种癌症类型中具有致癌潜力。致癌转录因子AP-1与特定的DNA靶点(5‘TCA[G/C]TGA)结合，但其实现的物理机制尚未确定。原型AP-1复合体是由CFO和cJun形成的，它们通过亮氨酸拉链结构域进行异源二聚。我们在体外用实时单分子荧光成像技术研究了AP-1与DNA钢索相互作用的DNA结合bZIP结构域。我们发现，由CFO：cJun和cJun：cJun组成的AP-1 bZIP结构域通过一维扩散搜索快速扫描DNA，平均扩散常数分别为0.14μM2s−1和0.26μM2s−1。我们还首次报道了CFO能够作为单体和同源二聚体的混合群体与DNA(0.29μM2−1)结合并在其上扩散，尽管先前的研究表明它不能独立结合DNA。此外，我们注意到，与cJun：cJun均二聚体相比，CFO：cJun异二聚体的暂停寿命延长，并能够在扩散数据中检测到明显的暂停行为。了解CFO：cJun和其他转录因子如何识别他们的靶标，对于利用这些搜索机制靶向DNA结合蛋白的新疗法的开发具有高度的相关性。
AP-1 proteins are members of the basic leucine zipper (bZIP) family of dimeric transcription factors, which facilitate a multitude of cellular processes, but are primarily known for their oncogenic potential in several cancer types. The oncogenic transcription factor AP-1 binds a specific DNA target site (5’TCA[G/C]TGA), however the physical mechanism of how this is achieved has not been determined. The archetypal AP-1 complex is formed by cFos and cJun, which heterodimerize via their leucine zipper domains. We investigated the DNA-binding bZIP domains of AP-1 interacting with DNA tightropes using real-time single molecule fluorescence imagingin vitro. We find that AP-1 bZIP domains comprising cFos:cJun and cJun:cJun rapidly scan DNA using a 1D diffusional search with average diffusion constants of 0.14 μm2s−1and 0.26 μm2s−1respectively. We also report for the first time that cFos is able to bind to and diffuse on DNA (0.29 μm2s−1) as a mixed population of monomers and homodimers, despite previous studies suggesting that it is incapable of independent DNA binding. Additionally, we note increased pause lifetimes for the cFos:cJun heterodimer compared to the cJun:cJun homodimer, and were able to detect distinct pausing behaviours within diffusion data. Understanding how cFos:cJun and other transcription factors identify their targets is highly relevant to the development of new therapeutics which target DNA binding proteins using these search mechanisms.
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影响因子：
14.9
作者：
Mahmutovic A;Berg OG;Elf J
通讯作者：
Elf J
心肌细胞氧化还原或代谢应激对 fos 和 jun 立即早期基因的调节。
影响因子：
20.1
作者：
Webster,KA;Discher,DJ;Bishopric,NH
通讯作者：
Bishopric,NH
影响因子：
3.7
作者：
Rao T;Ruiz-Gómez G;Hill TA;Hoang HN;Fairlie DP;Mason JM
通讯作者：
Mason JM
影响因子：
3.3
作者：
Bagchi, Biman;Blainey, Paul C.;Xie, X. Sunney
通讯作者：
Xie, X. Sunney
DOI：
10.1073/pnas.0805050105
发表时间：
2008-09-16
影响因子：
11.1
作者：
Doucleff, Michaeleen;Clore, G. Marius
通讯作者：
Clore, G. Marius