Pub Date : 2024-04-22DOI: 10.1038/s41594-024-01294-7
Julio C. Y. Liu, Leena Ackermann, Saskia Hoffmann, Zita Gál, Ivo A. Hendriks, Charu Jain, Louise Morlot, Michael H. Tatham, Gian-Luca McLelland, Ronald T. Hay, Michael Lund Nielsen, Thijn Brummelkamp, Peter Haahr, Niels Mailand
Protein SUMOylation provides a principal driving force for cellular stress responses, including DNA–protein crosslink (DPC) repair and arsenic-induced PML body degradation. In this study, using genome-scale screens, we identified the human E3 ligase TOPORS as a key effector of SUMO-dependent DPC resolution. We demonstrate that TOPORS promotes DPC repair by functioning as a SUMO-targeted ubiquitin ligase (STUbL), combining ubiquitin ligase activity through its RING domain with poly-SUMO binding via SUMO-interacting motifs, analogous to the STUbL RNF4. Mechanistically, TOPORS is a SUMO1-selective STUbL that complements RNF4 in generating complex ubiquitin landscapes on SUMOylated targets, including DPCs and PML, stimulating efficient p97/VCP unfoldase recruitment and proteasomal degradation. Combined loss of TOPORS and RNF4 is synthetic lethal even in unstressed cells, involving defective clearance of SUMOylated proteins from chromatin accompanied by cell cycle arrest and apoptosis. Our findings establish TOPORS as a STUbL whose parallel action with RNF4 defines a general mechanistic principle in crucial cellular processes governed by direct SUMO–ubiquitin crosstalk. Liu et al. reveal that human TOPORS is a SUMO1-selective SUMO-targeted ubiquitin ligase (STUbL). The parallel action of TOPORS and the STUbL RNF4 defines a general mechanistic principle governing pathways driven by direct SUMO–ubiquitin crosstalk.
{"title":"Concerted SUMO-targeted ubiquitin ligase activities of TOPORS and RNF4 are essential for stress management and cell proliferation","authors":"Julio C. Y. Liu, Leena Ackermann, Saskia Hoffmann, Zita Gál, Ivo A. Hendriks, Charu Jain, Louise Morlot, Michael H. Tatham, Gian-Luca McLelland, Ronald T. Hay, Michael Lund Nielsen, Thijn Brummelkamp, Peter Haahr, Niels Mailand","doi":"10.1038/s41594-024-01294-7","DOIUrl":"10.1038/s41594-024-01294-7","url":null,"abstract":"Protein SUMOylation provides a principal driving force for cellular stress responses, including DNA–protein crosslink (DPC) repair and arsenic-induced PML body degradation. In this study, using genome-scale screens, we identified the human E3 ligase TOPORS as a key effector of SUMO-dependent DPC resolution. We demonstrate that TOPORS promotes DPC repair by functioning as a SUMO-targeted ubiquitin ligase (STUbL), combining ubiquitin ligase activity through its RING domain with poly-SUMO binding via SUMO-interacting motifs, analogous to the STUbL RNF4. Mechanistically, TOPORS is a SUMO1-selective STUbL that complements RNF4 in generating complex ubiquitin landscapes on SUMOylated targets, including DPCs and PML, stimulating efficient p97/VCP unfoldase recruitment and proteasomal degradation. Combined loss of TOPORS and RNF4 is synthetic lethal even in unstressed cells, involving defective clearance of SUMOylated proteins from chromatin accompanied by cell cycle arrest and apoptosis. Our findings establish TOPORS as a STUbL whose parallel action with RNF4 defines a general mechanistic principle in crucial cellular processes governed by direct SUMO–ubiquitin crosstalk. Liu et al. reveal that human TOPORS is a SUMO1-selective SUMO-targeted ubiquitin ligase (STUbL). The parallel action of TOPORS and the STUbL RNF4 defines a general mechanistic principle governing pathways driven by direct SUMO–ubiquitin crosstalk.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 9","pages":"1355-1367"},"PeriodicalIF":12.5,"publicationDate":"2024-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41594-024-01294-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140632303","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-18DOI: 10.1038/s41594-024-01305-7
Dimitris Typas
{"title":"Macrophages need to release the proximal brake to degrade cellular corpses","authors":"Dimitris Typas","doi":"10.1038/s41594-024-01305-7","DOIUrl":"10.1038/s41594-024-01305-7","url":null,"abstract":"","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 4","pages":"586-586"},"PeriodicalIF":16.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140619838","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-18DOI: 10.1038/s41594-024-01271-0
Simon Newstead
Solute carriers (SLCs) control the flow of small molecules and ions across biological membranes. Over the last 20 years, the pace of research in SLC biology has accelerated markedly, opening new opportunities to treat metabolic diseases, cancer and neurological disorders. Recently, new families of atypical SLCs, with roles in organelle biology, metabolite signaling and trafficking, have expanded their roles in the cell. This Perspective discusses work leading to current advances and the emerging opportunities to target and modulate SLCs to uncover new biology and treat human disease. In this Perspective, the author describes the recent progress in understanding solute carrier (SLC) biology and discusses the roles of new families of atypical SLCs.
{"title":"Future opportunities in solute carrier structural biology","authors":"Simon Newstead","doi":"10.1038/s41594-024-01271-0","DOIUrl":"10.1038/s41594-024-01271-0","url":null,"abstract":"Solute carriers (SLCs) control the flow of small molecules and ions across biological membranes. Over the last 20 years, the pace of research in SLC biology has accelerated markedly, opening new opportunities to treat metabolic diseases, cancer and neurological disorders. Recently, new families of atypical SLCs, with roles in organelle biology, metabolite signaling and trafficking, have expanded their roles in the cell. This Perspective discusses work leading to current advances and the emerging opportunities to target and modulate SLCs to uncover new biology and treat human disease. In this Perspective, the author describes the recent progress in understanding solute carrier (SLC) biology and discusses the roles of new families of atypical SLCs.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 4","pages":"587-590"},"PeriodicalIF":16.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140619853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-18DOI: 10.1038/s41594-024-01303-9
The first membrane protein structure was reported almost 40 years ago. In this issue, we are publishing a set of papers that serve to underline the incredible advances in our understanding of the biology of these multifaceted molecular machines.
{"title":"Membrane-embedded machines","authors":"","doi":"10.1038/s41594-024-01303-9","DOIUrl":"10.1038/s41594-024-01303-9","url":null,"abstract":"The first membrane protein structure was reported almost 40 years ago. In this issue, we are publishing a set of papers that serve to underline the incredible advances in our understanding of the biology of these multifaceted molecular machines.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 4","pages":"579-579"},"PeriodicalIF":16.8,"publicationDate":"2024-04-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41594-024-01303-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140619872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-17DOI: 10.1038/s41594-024-01260-3
Yining Jiang, Atsushi Miyagi, Xiaoyu Wang, Biao Qiu, Olga Boudker, Simon Scheuring
The Pyrococcus horikoshii amino acid transporter GltPh revealed, like other channels and transporters, activity mode switching, previously termed wanderlust kinetics. Unfortunately, to date, the basis of these activity fluctuations is not understood, probably due to a lack of experimental tools that directly access the structural features of transporters related to their instantaneous activity. Here, we take advantage of high-speed atomic force microscopy, unique in providing simultaneous structural and temporal resolution, to uncover the basis of kinetic mode switching in proteins. We developed membrane extension membrane protein reconstitution that allows the analysis of isolated molecules. Together with localization atomic force microscopy, principal component analysis and hidden Markov modeling, we could associate structural states to a functional timeline, allowing six structures to be solved from a single molecule, and an inward-facing state, IFSopen-1, to be determined as a kinetic dead-end in the conformational landscape. The approaches presented on GltPh are generally applicable and open possibilities for time-resolved dynamic single-molecule structural biology. Combining high-speed atomic force microscopy (AFM) with localization AFM and principal component analysis, the authors present six structures of a glutamate transporter and associate the conformational states to the molecule’s activity timeline.
{"title":"HS-AFM single-molecule structural biology uncovers basis of transporter wanderlust kinetics","authors":"Yining Jiang, Atsushi Miyagi, Xiaoyu Wang, Biao Qiu, Olga Boudker, Simon Scheuring","doi":"10.1038/s41594-024-01260-3","DOIUrl":"10.1038/s41594-024-01260-3","url":null,"abstract":"The Pyrococcus horikoshii amino acid transporter GltPh revealed, like other channels and transporters, activity mode switching, previously termed wanderlust kinetics. Unfortunately, to date, the basis of these activity fluctuations is not understood, probably due to a lack of experimental tools that directly access the structural features of transporters related to their instantaneous activity. Here, we take advantage of high-speed atomic force microscopy, unique in providing simultaneous structural and temporal resolution, to uncover the basis of kinetic mode switching in proteins. We developed membrane extension membrane protein reconstitution that allows the analysis of isolated molecules. Together with localization atomic force microscopy, principal component analysis and hidden Markov modeling, we could associate structural states to a functional timeline, allowing six structures to be solved from a single molecule, and an inward-facing state, IFSopen-1, to be determined as a kinetic dead-end in the conformational landscape. The approaches presented on GltPh are generally applicable and open possibilities for time-resolved dynamic single-molecule structural biology. Combining high-speed atomic force microscopy (AFM) with localization AFM and principal component analysis, the authors present six structures of a glutamate transporter and associate the conformational states to the molecule’s activity timeline.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 8","pages":"1286-1295"},"PeriodicalIF":12.5,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140603972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-17DOI: 10.1038/s41594-024-01261-2
Matthias Eibauer, Miriam S. Weber, Rafael Kronenberg-Tenga, Charlie T. Beales, Rajaa Boujemaa-Paterski, Yagmur Turgay, Suganya Sivagurunathan, Julia Kraxner, Sarah Köster, Robert D. Goldman, Ohad Medalia
Intermediate filaments (IFs) are integral components of the cytoskeleton. They provide cells with tissue-specific mechanical properties and are involved in numerous cellular processes. Due to their intricate architecture, a 3D structure of IFs has remained elusive. Here we use cryo-focused ion-beam milling, cryo-electron microscopy and tomography to obtain a 3D structure of vimentin IFs (VIFs). VIFs assemble into a modular, intertwined and flexible helical structure of 40 α-helices in cross-section, organized into five protofibrils. Surprisingly, the intrinsically disordered head domains form a fiber in the lumen of VIFs, while the intrinsically disordered tails form lateral connections between the protofibrils. Our findings demonstrate how protein domains of low sequence complexity can complement well-folded protein domains to construct a biopolymer with striking mechanical strength and stretchability. Using cryo-electron microscopy and integrative modeling, the authors defined the structure of vimentin intermediate filaments, revealing a helical tube built of five protofibrils that enclose a fiber of low-complexity N-terminal domains.
{"title":"Vimentin filaments integrate low-complexity domains in a complex helical structure","authors":"Matthias Eibauer, Miriam S. Weber, Rafael Kronenberg-Tenga, Charlie T. Beales, Rajaa Boujemaa-Paterski, Yagmur Turgay, Suganya Sivagurunathan, Julia Kraxner, Sarah Köster, Robert D. Goldman, Ohad Medalia","doi":"10.1038/s41594-024-01261-2","DOIUrl":"10.1038/s41594-024-01261-2","url":null,"abstract":"Intermediate filaments (IFs) are integral components of the cytoskeleton. They provide cells with tissue-specific mechanical properties and are involved in numerous cellular processes. Due to their intricate architecture, a 3D structure of IFs has remained elusive. Here we use cryo-focused ion-beam milling, cryo-electron microscopy and tomography to obtain a 3D structure of vimentin IFs (VIFs). VIFs assemble into a modular, intertwined and flexible helical structure of 40 α-helices in cross-section, organized into five protofibrils. Surprisingly, the intrinsically disordered head domains form a fiber in the lumen of VIFs, while the intrinsically disordered tails form lateral connections between the protofibrils. Our findings demonstrate how protein domains of low sequence complexity can complement well-folded protein domains to construct a biopolymer with striking mechanical strength and stretchability. Using cryo-electron microscopy and integrative modeling, the authors defined the structure of vimentin intermediate filaments, revealing a helical tube built of five protofibrils that enclose a fiber of low-complexity N-terminal domains.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 6","pages":"939-949"},"PeriodicalIF":16.8,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41594-024-01261-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140603662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-17DOI: 10.1038/s41594-024-01286-7
Mitra Shokrollahi, Mia Stanic, Anisha Hundal, Janet N. Y. Chan, Defne Urman, Chris A. Jordan, Anne Hakem, Roderic Espin, Jun Hao, Rehna Krishnan, Philipp G. Maass, Brendan C. Dickson, Manoor P. Hande, Miquel A. Pujana, Razqallah Hakem, Karim Mekhail
Current models suggest that DNA double-strand breaks (DSBs) can move to the nuclear periphery for repair. It is unclear to what extent human DSBs display such repositioning. Here we show that the human nuclear envelope localizes to DSBs in a manner depending on DNA damage response (DDR) kinases and cytoplasmic microtubules acetylated by α-tubulin acetyltransferase-1 (ATAT1). These factors collaborate with the linker of nucleoskeleton and cytoskeleton complex (LINC), nuclear pore complex (NPC) protein NUP153, nuclear lamina and kinesins KIF5B and KIF13B to generate DSB-capturing nuclear envelope tubules (dsbNETs). dsbNETs are partly supported by nuclear actin filaments and the circadian factor PER1 and reversed by kinesin KIFC3. Although dsbNETs promote repair and survival, they are also co-opted during poly(ADP-ribose) polymerase (PARP) inhibition to restrain BRCA1-deficient breast cancer cells and are hyper-induced in cells expressing the aging-linked lamin A mutant progerin. In summary, our results advance understanding of nuclear structure–function relationships, uncover a nuclear–cytoplasmic DDR and identify dsbNETs as critical factors in genome organization and stability. Here the authors show that the nucleus undergoes a transient ‘metamorphosis’ within a nuclear–cytoplasmic DNA damage response linked to health and disease. Through this process, the nuclear envelope projects tubules that capture damaged DNA, mediating its repair.
{"title":"DNA double-strand break–capturing nuclear envelope tubules drive DNA repair","authors":"Mitra Shokrollahi, Mia Stanic, Anisha Hundal, Janet N. Y. Chan, Defne Urman, Chris A. Jordan, Anne Hakem, Roderic Espin, Jun Hao, Rehna Krishnan, Philipp G. Maass, Brendan C. Dickson, Manoor P. Hande, Miquel A. Pujana, Razqallah Hakem, Karim Mekhail","doi":"10.1038/s41594-024-01286-7","DOIUrl":"10.1038/s41594-024-01286-7","url":null,"abstract":"Current models suggest that DNA double-strand breaks (DSBs) can move to the nuclear periphery for repair. It is unclear to what extent human DSBs display such repositioning. Here we show that the human nuclear envelope localizes to DSBs in a manner depending on DNA damage response (DDR) kinases and cytoplasmic microtubules acetylated by α-tubulin acetyltransferase-1 (ATAT1). These factors collaborate with the linker of nucleoskeleton and cytoskeleton complex (LINC), nuclear pore complex (NPC) protein NUP153, nuclear lamina and kinesins KIF5B and KIF13B to generate DSB-capturing nuclear envelope tubules (dsbNETs). dsbNETs are partly supported by nuclear actin filaments and the circadian factor PER1 and reversed by kinesin KIFC3. Although dsbNETs promote repair and survival, they are also co-opted during poly(ADP-ribose) polymerase (PARP) inhibition to restrain BRCA1-deficient breast cancer cells and are hyper-induced in cells expressing the aging-linked lamin A mutant progerin. In summary, our results advance understanding of nuclear structure–function relationships, uncover a nuclear–cytoplasmic DDR and identify dsbNETs as critical factors in genome organization and stability. Here the authors show that the nucleus undergoes a transient ‘metamorphosis’ within a nuclear–cytoplasmic DNA damage response linked to health and disease. Through this process, the nuclear envelope projects tubules that capture damaged DNA, mediating its repair.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 9","pages":"1319-1330"},"PeriodicalIF":12.5,"publicationDate":"2024-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140603637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-16DOI: 10.1038/s41594-024-01283-w
Xiao-Yuan Yang, Zhangfei Shen, Jiale Xie, Jacelyn Greenwald, Ila Marathe, Qingpeng Lin, Wen Jun Xie, Vicki H. Wysocki, Tian-Min Fu
As one of the most prevalent anti-phage defense systems in prokaryotes, Gabija consists of a Gabija protein A (GajA) and a Gabija protein B (GajB). The assembly and function of the Gabija system remain unclear. Here we present cryo-EM structures of Bacillus cereus GajA and GajAB complex, revealing tetrameric and octameric assemblies, respectively. In the center of the complex, GajA assembles into a tetramer, which recruits two sets of GajB dimer at opposite sides of the complex, resulting in a 4:4 GajAB supramolecular complex for anti-phage defense. Further biochemical analysis showed that GajA alone is sufficient to cut double-stranded DNA and plasmid DNA, which can be inhibited by ATP. Unexpectedly, the GajAB displays enhanced activity for plasmid DNA, suggesting a role of substrate selection by GajB. Together, our study defines a framework for understanding anti-phage immune defense by the GajAB complex. The Gabija system constitutes one of the most prevalent anti-phage defense systems and is composed of GajA and GajB. Here, using cryo-EM and biochemistry, the authors show that GajA and GajB form a supramolecular complex with a stoichiometry of 4:4 to promote anti-phage defense.
作为原核生物中最普遍的抗噬菌体防御系统之一，Gabija 由 Gabija 蛋白 A（GajA）和 Gabija 蛋白 B（GajB）组成。Gabija系统的组装和功能仍不清楚。在这里，我们展示了蜡样芽孢杆菌 GajA 和 GajAB 复合物的冷冻电镜结构，分别揭示了四聚体和八聚体的组装。在复合物的中心，GajA组装成一个四聚体，它在复合物的相对两侧招募了两组GajB二聚体，从而形成了一个4:4的GajAB超分子复合物，用于抗蚜虫防御。进一步的生化分析表明，单靠 GajA 就足以切割双链 DNA 和质粒 DNA，而 ATP 可以抑制这种切割。意想不到的是，GajAB 对质粒 DNA 的活性增强了，这表明 GajB 在底物选择方面发挥了作用。总之，我们的研究为了解 GajAB 复合物的抗噬菌体免疫防御功能提供了一个框架。
{"title":"Molecular basis of Gabija anti-phage supramolecular assemblies","authors":"Xiao-Yuan Yang, Zhangfei Shen, Jiale Xie, Jacelyn Greenwald, Ila Marathe, Qingpeng Lin, Wen Jun Xie, Vicki H. Wysocki, Tian-Min Fu","doi":"10.1038/s41594-024-01283-w","DOIUrl":"10.1038/s41594-024-01283-w","url":null,"abstract":"As one of the most prevalent anti-phage defense systems in prokaryotes, Gabija consists of a Gabija protein A (GajA) and a Gabija protein B (GajB). The assembly and function of the Gabija system remain unclear. Here we present cryo-EM structures of Bacillus cereus GajA and GajAB complex, revealing tetrameric and octameric assemblies, respectively. In the center of the complex, GajA assembles into a tetramer, which recruits two sets of GajB dimer at opposite sides of the complex, resulting in a 4:4 GajAB supramolecular complex for anti-phage defense. Further biochemical analysis showed that GajA alone is sufficient to cut double-stranded DNA and plasmid DNA, which can be inhibited by ATP. Unexpectedly, the GajAB displays enhanced activity for plasmid DNA, suggesting a role of substrate selection by GajB. Together, our study defines a framework for understanding anti-phage immune defense by the GajAB complex. The Gabija system constitutes one of the most prevalent anti-phage defense systems and is composed of GajA and GajB. Here, using cryo-EM and biochemistry, the authors show that GajA and GajB form a supramolecular complex with a stoichiometry of 4:4 to promote anti-phage defense.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 8","pages":"1243-1250"},"PeriodicalIF":12.5,"publicationDate":"2024-04-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140556866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-04-12DOI: 10.1038/s41594-024-01281-y
Tom Dendooven, Stanislau Yatskevich, Alister Burt, Zhuo A. Chen, Dom Bellini, Juri Rappsilber, John V. Kilmartin, David Barford
Microtubule (MT) filaments, composed of α/β-tubulin dimers, are fundamental to cellular architecture, function and organismal development. They are nucleated from MT organizing centers by the evolutionarily conserved γ-tubulin ring complex (γTuRC). However, the molecular mechanism of nucleation remains elusive. Here we used cryo-electron tomography to determine the structure of the native γTuRC capping the minus end of a MT in the context of enriched budding yeast spindles. In our structure, γTuRC presents a ring of γ-tubulin subunits to seed nucleation of exclusively 13-protofilament MTs, adopting an active closed conformation to function as a perfect geometric template for MT nucleation. Our cryo-electron tomography reconstruction revealed that a coiled-coil protein staples the first row of α/β-tubulin of the MT to alternating positions along the γ-tubulin ring of γTuRC. This positioning of α/β-tubulin onto γTuRC suggests a role for the coiled-coil protein in augmenting γTuRC-mediated MT nucleation. Based on our results, we describe a molecular model for budding yeast γTuRC activation and MT nucleation. Using cryo-electron tomography, Dendooven et al. determined the structure of the native budding yeast γ-tubulin ring complex (γTuRC) capping spindle microtubules and showed that γTuRC adopts an active closed conformation to function as a perfect geometric template for microtubule nucleation.
{"title":"Structure of the native γ-tubulin ring complex capping spindle microtubules","authors":"Tom Dendooven, Stanislau Yatskevich, Alister Burt, Zhuo A. Chen, Dom Bellini, Juri Rappsilber, John V. Kilmartin, David Barford","doi":"10.1038/s41594-024-01281-y","DOIUrl":"10.1038/s41594-024-01281-y","url":null,"abstract":"Microtubule (MT) filaments, composed of α/β-tubulin dimers, are fundamental to cellular architecture, function and organismal development. They are nucleated from MT organizing centers by the evolutionarily conserved γ-tubulin ring complex (γTuRC). However, the molecular mechanism of nucleation remains elusive. Here we used cryo-electron tomography to determine the structure of the native γTuRC capping the minus end of a MT in the context of enriched budding yeast spindles. In our structure, γTuRC presents a ring of γ-tubulin subunits to seed nucleation of exclusively 13-protofilament MTs, adopting an active closed conformation to function as a perfect geometric template for MT nucleation. Our cryo-electron tomography reconstruction revealed that a coiled-coil protein staples the first row of α/β-tubulin of the MT to alternating positions along the γ-tubulin ring of γTuRC. This positioning of α/β-tubulin onto γTuRC suggests a role for the coiled-coil protein in augmenting γTuRC-mediated MT nucleation. Based on our results, we describe a molecular model for budding yeast γTuRC activation and MT nucleation. Using cryo-electron tomography, Dendooven et al. determined the structure of the native budding yeast γ-tubulin ring complex (γTuRC) capping spindle microtubules and showed that γTuRC adopts an active closed conformation to function as a perfect geometric template for microtubule nucleation.","PeriodicalId":49141,"journal":{"name":"Nature Structural & Molecular Biology","volume":"31 7","pages":"1134-1144"},"PeriodicalIF":12.5,"publicationDate":"2024-04-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41594-024-01281-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140547449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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