Pub Date : 2024-11-13DOI: 10.1016/j.str.2024.10.026
Cheng Li, Yunqiang Bian, Yiting Tang, Lingyu Meng, Peipei Yin, Ye Hong, Jun Cheng, Yuchen Li, Jie Lin, Chao Tang, Chunlai Chen, Wenfei Li, Zhi Qi
Nucleic acid and protein co-condensates exhibit diverse morphologies crucial for fundamental cellular processes. Despite many previous studies that advanced our understanding of this topic, several interesting biophysical questions regarding the underlying molecular mechanisms remain. We investigated DNA and human transcription factor p53 co-condensates—a scenario where neither dsDNA nor the protein demonstrates phase-separation behavior individually. Through a combination of experimental assays and theoretical approaches, we elucidated: (1) the phase diagram of DNA-protein co-condensates at a certain observation time, identifying a phase transition between viscoelastic fluid and viscoelastic solid states, and a morphology transition from droplet-like to “pearl chain”-like co-condensates; (2) the growth dynamics of co-condensates. Droplet-like and “pearl chain”-like co-condensates share a common initial critical microscopic cluster size at the nanometer scale during the early stage of phase separation. These findings provide important insights into the biophysical mechanisms underlying multi-component phase separation within cellular environments.
{"title":"Deciphering the molecular mechanism underlying morphology transition in two-component DNA-protein cophase separation","authors":"Cheng Li, Yunqiang Bian, Yiting Tang, Lingyu Meng, Peipei Yin, Ye Hong, Jun Cheng, Yuchen Li, Jie Lin, Chao Tang, Chunlai Chen, Wenfei Li, Zhi Qi","doi":"10.1016/j.str.2024.10.026","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.026","url":null,"abstract":"Nucleic acid and protein co-condensates exhibit diverse morphologies crucial for fundamental cellular processes. Despite many previous studies that advanced our understanding of this topic, several interesting biophysical questions regarding the underlying molecular mechanisms remain. We investigated DNA and human transcription factor p53 co-condensates—a scenario where neither dsDNA nor the protein demonstrates phase-separation behavior individually. Through a combination of experimental assays and theoretical approaches, we elucidated: (1) the phase diagram of DNA-protein co-condensates at a certain observation time, identifying a phase transition between viscoelastic fluid and viscoelastic solid states, and a morphology transition from droplet-like to “pearl chain”-like co-condensates; (2) the growth dynamics of co-condensates. Droplet-like and “pearl chain”-like co-condensates share a common initial critical microscopic cluster size at the nanometer scale during the early stage of phase separation. These findings provide important insights into the biophysical mechanisms underlying multi-component phase separation within cellular environments.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"216 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142601001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-12DOI: 10.1016/j.str.2024.10.023
Neil J. Thomson, Ulrich Zachariae
Negative allosteric modulation of G-protein coupled receptors (GPCRs) by Na+ ions was first described in the 1970s for opioid receptors (ORs) and has subsequently been detected for most class A GPCRs. In high-resolution structures of inactive-state class A GPCRs, a Na+ ion binds to a conserved pocket near residue D2.50, whereas active-state structures of GPCRs are incompatible with Na+ binding. Correspondingly, Na+ diminishes agonist affinity, stabilizes the receptors in the inactive state, and reduces basal signaling. We applied a mutual-information based analysis to μs-timescale biomolecular simulations of the μ-opioid receptor (μ-OR). Our results reveal that Na+ binding is coupled to a water wire linking the Na+ binding site with the agonist binding pocket and to rearrangements in polar networks propagating conformational changes to the agonist and G-protein binding sites. These findings provide a new mechanistic link between the presence of the ion, altered agonist affinity, receptor deactivation, and lowered basal signaling levels.
20 世纪 70 年代,Na+ 离子对 G 蛋白偶联受体(GPCR)的负异位调节作用首次在阿片受体(ORs)中被描述,随后在大多数 A 类 GPCR 中也被检测到。在非活动状态 A 类 GPCR 的高分辨率结构中,Na+ 离子与残基 D2.50 附近的保守口袋结合,而活动状态的 GPCR 结构与 Na+ 结合不相容。相应地,Na+会降低激动剂的亲和力,使受体稳定在非活性状态,并减少基础信号传导。我们对μ-阿片受体(μ-OR)的μs-时间尺度生物分子模拟进行了基于相互信息的分析。我们的研究结果表明,Na+的结合与连接Na+结合位点和激动剂结合口袋的水丝以及极性网络的重排有关,而极性网络又将构象变化传播到激动剂和G蛋白结合位点。这些发现为离子的存在、激动剂亲和力的改变、受体失活和基础信号水平的降低之间提供了新的机理联系。
{"title":"Mechanism of negative μ-opioid receptor modulation by sodium ions","authors":"Neil J. Thomson, Ulrich Zachariae","doi":"10.1016/j.str.2024.10.023","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.023","url":null,"abstract":"Negative allosteric modulation of G-protein coupled receptors (GPCRs) by Na<sup>+</sup> ions was first described in the 1970s for opioid receptors (ORs) and has subsequently been detected for most class A GPCRs. In high-resolution structures of inactive-state class A GPCRs, a Na<sup>+</sup> ion binds to a conserved pocket near residue D2.50, whereas active-state structures of GPCRs are incompatible with Na<sup>+</sup> binding. Correspondingly, Na<sup>+</sup> diminishes agonist affinity, stabilizes the receptors in the inactive state, and reduces basal signaling. We applied a mutual-information based analysis to <em>μ</em>s-timescale biomolecular simulations of the <em>μ</em>-opioid receptor (<em>μ</em>-OR). Our results reveal that Na<sup>+</sup> binding is coupled to a water wire linking the Na<sup>+</sup> binding site with the agonist binding pocket and to rearrangements in polar networks propagating conformational changes to the agonist and G-protein binding sites. These findings provide a new mechanistic link between the presence of the ion, altered agonist affinity, receptor deactivation, and lowered basal signaling levels.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"15 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142599607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-08DOI: 10.1016/j.str.2024.10.022
Fabian Liessmann, Lukas von Bredow, Jens Meiler, Ines Liebscher
G protein-coupled receptors (GPCRs) orchestrate many physiological functions and are a crucial target in drug discovery. Adhesion GPCRs (aGPCRs), the second largest family within this superfamily, are promising yet underexplored targets for treating various diseases, including obesity, psychiatric disorders, and cancer. However, the receptors’ unique and complex structure and miscellaneous interactions complicate comprehensive pharmacological studies. Despite recent progress in determining structures and elucidation of the activation mechanism, the function of many receptors remains to be determined.This review consolidates current knowledge on aGPCR ligands, focusing on small molecule orthosteric ligands and allosteric modulators identified for the ADGRGs subfamily (subfamily VIII), (GPR56/ADGRG1, GPR64/ADGRG2, GPR97/ADGRG3, GPR114/ADGRG5, GPR126/ADGRG6, and GPR128/ADGRG7). We discuss challenges in hit identification, target validation, and drug discovery, highlighting molecular compositions and recent structural breakthroughs. ADGRG ligands can offer new insights into aGPCR modulation and have significant potential for novel therapeutic interventions targeting various diseases.
{"title":"Targeting adhesion G protein-coupled receptors. Current status and future perspectives","authors":"Fabian Liessmann, Lukas von Bredow, Jens Meiler, Ines Liebscher","doi":"10.1016/j.str.2024.10.022","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.022","url":null,"abstract":"G protein-coupled receptors (GPCRs) orchestrate many physiological functions and are a crucial target in drug discovery. Adhesion GPCRs (aGPCRs), the second largest family within this superfamily, are promising yet underexplored targets for treating various diseases, including obesity, psychiatric disorders, and cancer. However, the receptors’ unique and complex structure and miscellaneous interactions complicate comprehensive pharmacological studies. Despite recent progress in determining structures and elucidation of the activation mechanism, the function of many receptors remains to be determined.This review consolidates current knowledge on aGPCR ligands, focusing on small molecule orthosteric ligands and allosteric modulators identified for the ADGRGs subfamily (subfamily VIII), (GPR56/ADGRG1, GPR64/ADGRG2, GPR97/ADGRG3, GPR114/ADGRG5, GPR126/ADGRG6, and GPR128/ADGRG7). We discuss challenges in hit identification, target validation, and drug discovery, highlighting molecular compositions and recent structural breakthroughs. ADGRG ligands can offer new insights into aGPCR modulation and have significant potential for novel therapeutic interventions targeting various diseases.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"145 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596474","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-07DOI: 10.1016/j.str.2024.10.015
Shalini Iyer, Chittaranjan Das
Phosphorylation of ubiquitin and the ubiquitin-like domain of Parkin, mediated by the kinase PINK1, is essential for the liberation of the E3 ligase from its autoinhibited state. In this issue of Structure, Lenka et al.1 provide the structural basis for the specificity and stronger Parkin activation by phospho-NEDD8 compared to phospho-ubiquitin.
{"title":"Ringing the changes: Regulation of Parkin activity by different ubiquitin and ubiquitin-like proteins","authors":"Shalini Iyer, Chittaranjan Das","doi":"10.1016/j.str.2024.10.015","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.015","url":null,"abstract":"Phosphorylation of ubiquitin and the ubiquitin-like domain of Parkin, mediated by the kinase PINK1, is essential for the liberation of the E3 ligase from its autoinhibited state. In this issue of <em>Structure</em>, Lenka et al.<span><span><sup>1</sup></span></span> provide the structural basis for the specificity and stronger Parkin activation by phospho-NEDD8 compared to phospho-ubiquitin.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"95 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-07DOI: 10.1016/j.str.2024.10.017
Wang Xu, Yang Han, Maolin Lu
In this issue of Structure, Dey et al.1 employ single-molecule FRET to map the conformational trajectory of Omicron spikes during fusion, revealing a transition from pre-fusion to post-fusion through two intermediates. This study highlights the roles of acidic environments, Ca2+, and receptors in promoting SARS-CoV-2 cell entry.
{"title":"Multi-step shapeshifting of SARS-CoV-2 Omicron spikes during fusion","authors":"Wang Xu, Yang Han, Maolin Lu","doi":"10.1016/j.str.2024.10.017","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.017","url":null,"abstract":"In this issue of <em>Structure</em>, Dey et al.<span><span><sup>1</sup></span></span> employ single-molecule FRET to map the conformational trajectory of Omicron spikes during fusion, revealing a transition from pre-fusion to post-fusion through two intermediates. This study highlights the roles of acidic environments, Ca<sup>2+</sup>, and receptors in promoting SARS-CoV-2 cell entry.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"13 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-07DOI: 10.1016/j.str.2024.10.006
Taku Mizutani, Ikuro Abe
The enzymatically regioselective catalyzed incorporation of cysteine sulfoxide into histidine generates physiologically important antioxidants such as ergothioneine and ovothiol. In this issue of Structure, Ireland et al.1 report the crystal structure of EgtB-IV, which provides insights into the convergent evolution of sulfoxide synthase.
{"title":"Traces of convergent evolution left in the structure of EgtB-IV","authors":"Taku Mizutani, Ikuro Abe","doi":"10.1016/j.str.2024.10.006","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.006","url":null,"abstract":"The enzymatically regioselective catalyzed incorporation of cysteine sulfoxide into histidine generates physiologically important antioxidants such as ergothioneine and ovothiol. In this issue of <em>Structure</em>, Ireland et al.<span><span><sup>1</sup></span></span> report the crystal structure of EgtB-IV, which provides insights into the convergent evolution of sulfoxide synthase.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"9 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-07DOI: 10.1016/j.str.2024.10.010
Qingtong Zhou, Xiao Liu, Ming-Wei Wang
In this issue of Structure, Shaw et al.1 visualize the PI4KA-TTC7B-FAM126A-calcineurin complex by combining cryo-EM, HDX-MS, and AlphaFold3, and reveal a dual interaction of calcineurin with PI4KA and FAM126A. This work promotes our understanding of calcineurin-regulated PI4KA activity and paves the way for further exploration of the roles of PI4KA in the plasma membrane.
{"title":"Visualizing the dual interaction of calcineurin with PI4KA and FAM126A","authors":"Qingtong Zhou, Xiao Liu, Ming-Wei Wang","doi":"10.1016/j.str.2024.10.010","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.010","url":null,"abstract":"In this issue of <em>Structure</em>, Shaw et al.<span><span><sup>1</sup></span></span> visualize the PI4KA-TTC7B-FAM126A-calcineurin complex by combining cryo-EM, HDX-MS, and AlphaFold3, and reveal a dual interaction of calcineurin with PI4KA and FAM126A. This work promotes our understanding of calcineurin-regulated PI4KA activity and paves the way for further exploration of the roles of PI4KA in the plasma membrane.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"18 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142598266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-07DOI: 10.1016/j.str.2024.10.007
Rosemary J. Cater, Renae M. Ryan, Jonathan S. Oakhill, Peter Czabotar, James M. Murphy, Melissa J. Call
Since 1976, the Lorne Proteins Conference has been a key gathering for protein scientists, combining cutting-edge research with community engagement in a picturesque corner of the world. Renowned for its diverse international speakers and collaborative spirit, the conference looks forward to its 50th anniversary in 2025.
{"title":"Structure, function, surf, repeat: A week at Lorne Proteins 2024","authors":"Rosemary J. Cater, Renae M. Ryan, Jonathan S. Oakhill, Peter Czabotar, James M. Murphy, Melissa J. Call","doi":"10.1016/j.str.2024.10.007","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.007","url":null,"abstract":"Since 1976, the Lorne Proteins Conference has been a key gathering for protein scientists, combining cutting-edge research with community engagement in a picturesque corner of the world. Renowned for its diverse international speakers and collaborative spirit, the conference looks forward to its 50<sup>th</sup> anniversary in 2025.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"4 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142596475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-06DOI: 10.1016/j.str.2024.10.009
Rawia Hamid, Danica J. Walsh, Eleonora Diamanti, Diana Aguilar, Antoine Lacour, Mostafa M. Hamed, Anna K.H. Hirsch
Enzymes of the methylerythritol phosphate (MEP) pathway are potential targets for antimicrobial drug discovery. Here, we focus on 4-diphosphocytidyl-2-C-methyl-D-erythritol (IspE) kinase from the MEP pathway. We use biochemical and structural biology methods to investigate homologs from pathogenic microorganisms; Escherichia coli, Klebsiella pneumoniae, and Acinetobacter baumannii. We determined the X-ray crystal structures of IspE-inhibitor complexes and studied inhibitors’ binding modes targeting the substrate pocket. The experimental results indicate the need for distinct inhibitor strategies due to structural differences among IspE homologs, particularly for A. baumannii IspE, which displays a unique inhibitory profile due to a tighter hydrophobic subpocket in the substrate binding site. This study enhances our understanding of the MEP enzymes and sets the stage for structure-based drug design of selective inhibitors to combat pathogenic microorganisms.
{"title":"IspE kinase as an anti-infective target: Role of a hydrophobic pocket in inhibitor binding","authors":"Rawia Hamid, Danica J. Walsh, Eleonora Diamanti, Diana Aguilar, Antoine Lacour, Mostafa M. Hamed, Anna K.H. Hirsch","doi":"10.1016/j.str.2024.10.009","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.009","url":null,"abstract":"Enzymes of the methylerythritol phosphate (MEP) pathway are potential targets for antimicrobial drug discovery. Here, we focus on 4-diphosphocytidyl-2-<em>C</em>-methyl-D-erythritol (IspE) kinase from the MEP pathway. We use biochemical and structural biology methods to investigate homologs from pathogenic microorganisms; <em>Escherichia coli</em>, <em>Klebsiella pneumoniae</em>, and <em>Acinetobacter baumannii</em>. We determined the X-ray crystal structures of IspE-inhibitor complexes and studied inhibitors’ binding modes targeting the substrate pocket. The experimental results indicate the need for distinct inhibitor strategies due to structural differences among IspE homologs, particularly for <em>A. baumannii</em> IspE, which displays a unique inhibitory profile due to a tighter hydrophobic subpocket in the substrate binding site. This study enhances our understanding of the MEP enzymes and sets the stage for structure-based drug design of selective inhibitors to combat pathogenic microorganisms.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"25 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142589076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The CNNM/CorC Mg2+ transporters are widely conserved in eukaryotes (cyclin M [CNNM]) and prokaryotes (CorC) and participate in various biological processes. Previous structural analyses of the CorC transmembrane domain in the Mg2+-bound inward-facing conformation revealed the conserved Mg2+ recognition mechanism in the CNNM/CorC family; however, the conformational dynamics in the Mg2+ transport cycle remain unclear because structures in other conformations are unknown. Here, we used AlphaFold structure prediction to predict the occluded-like and outward-facing-like conformations of the CorC and CNNM proteins and identified conserved hydrophilic interactions close to the cytoplasmic side in these conformations. Molecular dynamics simulations and biochemical cross-linking showed that these conserved hydrophilic interactions are stable, especially in the outward-facing-like conformation. Furthermore, mutational analysis revealed that the residues involved in these hydrophilic interactions on the cytoplasmic side are important for Mg2+ transport in the CorC and CNNM proteins. Our work provides mechanistic insights into the transport cycle of the CNNM/CorC family.
CNNM/CorC Mg2+ 转运体在真核生物(细胞周期蛋白 M [CNNM])和原核生物(CorC)中广泛保守,参与各种生物过程。之前对处于 Mg2+ 结合内向构象的 CorC 跨膜结构域进行的结构分析揭示了 CNNM/CorC 家族中保守的 Mg2+ 识别机制;然而,由于其他构象的结构未知,Mg2+ 转运循环中的构象动态仍不清楚。在此,我们利用 AlphaFold 结构预测法预测了 CorC 和 CNNM 蛋白的闭锁样构象和外向样构象,并确定了这些构象中靠近细胞质侧的保守亲水相互作用。分子动力学模拟和生化交联表明,这些保守的亲水相互作用是稳定的,尤其是在向外型构象中。此外,突变分析表明,参与细胞质侧这些亲水相互作用的残基对 CorC 和 CNNM 蛋白的 Mg2+ 运输非常重要。我们的研究为 CNNM/CorC 家族的转运循环提供了机制上的启示。
{"title":"AI-driven mechanistic analysis of conformational dynamics in CNNM/CorC Mg2+ transporters","authors":"Jie Ma, Xingyu Song, Yosuke Funato, Xinyu Teng, Yichen Huang, Hiroaki Miki, Wenning Wang, Motoyuki Hattori","doi":"10.1016/j.str.2024.10.021","DOIUrl":"https://doi.org/10.1016/j.str.2024.10.021","url":null,"abstract":"The CNNM/CorC Mg<sup>2+</sup> transporters are widely conserved in eukaryotes (cyclin M [CNNM]) and prokaryotes (CorC) and participate in various biological processes. Previous structural analyses of the CorC transmembrane domain in the Mg<sup>2+</sup>-bound inward-facing conformation revealed the conserved Mg<sup>2+</sup> recognition mechanism in the CNNM/CorC family; however, the conformational dynamics in the Mg<sup>2+</sup> transport cycle remain unclear because structures in other conformations are unknown. Here, we used AlphaFold structure prediction to predict the occluded-like and outward-facing-like conformations of the CorC and CNNM proteins and identified conserved hydrophilic interactions close to the cytoplasmic side in these conformations. Molecular dynamics simulations and biochemical cross-linking showed that these conserved hydrophilic interactions are stable, especially in the outward-facing-like conformation. Furthermore, mutational analysis revealed that the residues involved in these hydrophilic interactions on the cytoplasmic side are important for Mg<sup>2+</sup> transport in the CorC and CNNM proteins. Our work provides mechanistic insights into the transport cycle of the CNNM/CorC family.","PeriodicalId":22168,"journal":{"name":"Structure","volume":"19 1","pages":""},"PeriodicalIF":5.7,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142588816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}