Pub Date : 2024-07-11DOI: 10.1038/s41556-024-01454-3
Fátima Gebauer
The role of RNA in preserving the integrity and dynamics of membrane-bound organelles remains largely unexplored. A study now identifies the Golgi-resident protein GM130 as an RNA-binding protein that scaffolds the Golgi ribbon in a polyadenylated-RNA-dependent manner.
{"title":"RNA glues it all","authors":"Fátima Gebauer","doi":"10.1038/s41556-024-01454-3","DOIUrl":"10.1038/s41556-024-01454-3","url":null,"abstract":"The role of RNA in preserving the integrity and dynamics of membrane-bound organelles remains largely unexplored. A study now identifies the Golgi-resident protein GM130 as an RNA-binding protein that scaffolds the Golgi ribbon in a polyadenylated-RNA-dependent manner.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141584269","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 : 2024-07-11DOI: 10.1038/s41556-024-01447-2
Yijun Zhang, Joachim Seemann
The mammalian Golgi is composed of stacks that are laterally connected into a continuous ribbon-like structure. The integrity and function of the ribbon is disrupted under stress conditions, but the molecular mechanisms remain unclear. Here we show that the ribbon is maintained by biomolecular condensates of RNA and the Golgi matrix protein GM130 (GOLGA2). We identify GM130 as a membrane-bound RNA-binding protein, which directly recruits RNA and associated RNA-binding proteins to the Golgi membrane. Acute degradation of RNA or GM130 in cells disrupts the ribbon. Under stress conditions, RNA dissociates from GM130 and the ribbon is disjointed, but after the cells recover from stress the ribbon is restored. When overexpressed in cells, GM130 forms RNA-dependent liquid-like condensates. GM130 contains an intrinsically disordered domain at its amino terminus, which binds RNA to induce liquid–liquid phase separation. These co-condensates are sufficient to link purified Golgi membranes, reconstructing lateral linking of stacks into a ribbon-like structure. Together, these studies show that RNA acts as a structural biopolymer that together with GM130 maintains the integrity of the Golgi ribbon. Zhang and Seemann show that GM130 forms a complex with RNA-binding proteins. RNA binding of GM130 induces liquid–liquid phase separation and these co-condensates function to link the Golgi ribbon.
{"title":"RNA scaffolds the Golgi ribbon by forming condensates with GM130","authors":"Yijun Zhang, Joachim Seemann","doi":"10.1038/s41556-024-01447-2","DOIUrl":"10.1038/s41556-024-01447-2","url":null,"abstract":"The mammalian Golgi is composed of stacks that are laterally connected into a continuous ribbon-like structure. The integrity and function of the ribbon is disrupted under stress conditions, but the molecular mechanisms remain unclear. Here we show that the ribbon is maintained by biomolecular condensates of RNA and the Golgi matrix protein GM130 (GOLGA2). We identify GM130 as a membrane-bound RNA-binding protein, which directly recruits RNA and associated RNA-binding proteins to the Golgi membrane. Acute degradation of RNA or GM130 in cells disrupts the ribbon. Under stress conditions, RNA dissociates from GM130 and the ribbon is disjointed, but after the cells recover from stress the ribbon is restored. When overexpressed in cells, GM130 forms RNA-dependent liquid-like condensates. GM130 contains an intrinsically disordered domain at its amino terminus, which binds RNA to induce liquid–liquid phase separation. These co-condensates are sufficient to link purified Golgi membranes, reconstructing lateral linking of stacks into a ribbon-like structure. Together, these studies show that RNA acts as a structural biopolymer that together with GM130 maintains the integrity of the Golgi ribbon. Zhang and Seemann show that GM130 forms a complex with RNA-binding proteins. RNA binding of GM130 induces liquid–liquid phase separation and these co-condensates function to link the Golgi ribbon.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141584271","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}
Currently, the dynamic accessible elements that determine regulatory programs responsible for the unique identity and function of each cell type during zebrafish embryogenesis lack detailed study. Here we present SPATAC-seq: a split-pool ligation-based assay for transposase-accessible chromatin using sequencing. Using SPATAC-seq, we profiled chromatin accessibility in more than 800,000 individual nuclei across 20 developmental stages spanning the sphere stage to the early larval protruding mouth stage. Using this chromatin accessibility map, we identified 604 cell states and inferred their developmental relationships. We also identified 959,040 candidate cis-regulatory elements (cCREs) and delineated development-specific cCREs, as well as transcription factors defining diverse cell identities. Importantly, enhancer reporter assays confirmed that the majority of tested cCREs exhibited robust enhanced green fluorescent protein expression in restricted cell types or tissues. Finally, we explored gene regulatory programs that drive pigment and notochord cell differentiation. Our work provides a valuable open resource for exploring driver regulators of cell fate decisions in zebrafish embryogenesis. In two independent studies, Sun, Liu et al. and Sun et al. develop SPATAC-seq to map the chromatin accessibility landscape of zebrafish embryogenesis and mouse organogenesis, respectively, and identify transcription regulators that determine cell fate.
{"title":"Mapping the chromatin accessibility landscape of zebrafish embryogenesis at single-cell resolution by SPATAC-seq","authors":"Keyong Sun, Xin Liu, Runda Xu, Chang Liu, Anming Meng, Xun Lan","doi":"10.1038/s41556-024-01449-0","DOIUrl":"10.1038/s41556-024-01449-0","url":null,"abstract":"Currently, the dynamic accessible elements that determine regulatory programs responsible for the unique identity and function of each cell type during zebrafish embryogenesis lack detailed study. Here we present SPATAC-seq: a split-pool ligation-based assay for transposase-accessible chromatin using sequencing. Using SPATAC-seq, we profiled chromatin accessibility in more than 800,000 individual nuclei across 20 developmental stages spanning the sphere stage to the early larval protruding mouth stage. Using this chromatin accessibility map, we identified 604 cell states and inferred their developmental relationships. We also identified 959,040 candidate cis-regulatory elements (cCREs) and delineated development-specific cCREs, as well as transcription factors defining diverse cell identities. Importantly, enhancer reporter assays confirmed that the majority of tested cCREs exhibited robust enhanced green fluorescent protein expression in restricted cell types or tissues. Finally, we explored gene regulatory programs that drive pigment and notochord cell differentiation. Our work provides a valuable open resource for exploring driver regulators of cell fate decisions in zebrafish embryogenesis. In two independent studies, Sun, Liu et al. and Sun et al. develop SPATAC-seq to map the chromatin accessibility landscape of zebrafish embryogenesis and mouse organogenesis, respectively, and identify transcription regulators that determine cell fate.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141557192","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 : 2024-07-08DOI: 10.1038/s41556-024-01435-6
Keyong Sun, Xin Liu, Xun Lan
Organogenesis is a highly complex and precisely regulated process. Here we profiled the chromatin accessibility in >350,000 cells derived from 13 mouse embryos at four developmental stages from embryonic day (E) 10.5 to E13.5 by SPATAC-seq in a single experiment. The resulting atlas revealed the status of 830,873 candidate cis-regulatory elements in 43 major cell types. By integrating the chromatin accessibility atlas with the previous transcriptomic dataset, we characterized cis-regulatory sequences and transcription factors associated with cell fate commitment, such as Nr5a2 in the development of gastrointestinal tract, which was preliminarily supported by the in vivo experiment in zebrafish. Finally, we integrated this atlas with the previous single-cell chromatin accessibility dataset from 13 adult mouse tissues to delineate the developmental stage-specific gene regulatory programmes within and across different cell types and identify potential molecular switches throughout lineage development. This comprehensive dataset provides a foundation for exploring transcriptional regulation in organogenesis. In two independent studies, Sun, Liu et al. and Sun et al. develop SPATAC-seq to map the chromatin accessibility landscape of zebrafish embryogenesis and mouse organogenesis, respectively, and identify transcription regulators that determine cell fate.
{"title":"A single-cell atlas of chromatin accessibility in mouse organogenesis","authors":"Keyong Sun, Xin Liu, Xun Lan","doi":"10.1038/s41556-024-01435-6","DOIUrl":"10.1038/s41556-024-01435-6","url":null,"abstract":"Organogenesis is a highly complex and precisely regulated process. Here we profiled the chromatin accessibility in >350,000 cells derived from 13 mouse embryos at four developmental stages from embryonic day (E) 10.5 to E13.5 by SPATAC-seq in a single experiment. The resulting atlas revealed the status of 830,873 candidate cis-regulatory elements in 43 major cell types. By integrating the chromatin accessibility atlas with the previous transcriptomic dataset, we characterized cis-regulatory sequences and transcription factors associated with cell fate commitment, such as Nr5a2 in the development of gastrointestinal tract, which was preliminarily supported by the in vivo experiment in zebrafish. Finally, we integrated this atlas with the previous single-cell chromatin accessibility dataset from 13 adult mouse tissues to delineate the developmental stage-specific gene regulatory programmes within and across different cell types and identify potential molecular switches throughout lineage development. This comprehensive dataset provides a foundation for exploring transcriptional regulation in organogenesis. In two independent studies, Sun, Liu et al. and Sun et al. develop SPATAC-seq to map the chromatin accessibility landscape of zebrafish embryogenesis and mouse organogenesis, respectively, and identify transcription regulators that determine cell fate.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141557137","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 : 2024-07-05DOI: 10.1038/s41556-024-01441-8
Johannes Pilic, Tatjana Kleele
Cellular organelles form an interconnected and dynamic network that orchestrates cellular functions. Using a multispectral imaging and computational analysis approach (‘OrgaPlexing’), a study now identifies multi-organelle units as crucial regulators of metabolic reprogramming in primary macrophages upon inflammatory stimuli.
{"title":"An organelle tango controls lipid metabolism","authors":"Johannes Pilic, Tatjana Kleele","doi":"10.1038/s41556-024-01441-8","DOIUrl":"10.1038/s41556-024-01441-8","url":null,"abstract":"Cellular organelles form an interconnected and dynamic network that orchestrates cellular functions. Using a multispectral imaging and computational analysis approach (‘OrgaPlexing’), a study now identifies multi-organelle units as crucial regulators of metabolic reprogramming in primary macrophages upon inflammatory stimuli.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141538203","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 : 2024-07-05DOI: 10.1038/s41556-024-01408-9
Jie Xu, Bing Ren
Transcription factors (TFs) and cis-regulatory elements (CREs) drive organism development. Suboptimal binding of TFs to CREs is shown to be key for the specificity of gene expression. New work now indicates that a similar principle governs the activities of TFs and their regulatory specificity.
{"title":"Built to be imperfect","authors":"Jie Xu, Bing Ren","doi":"10.1038/s41556-024-01408-9","DOIUrl":"10.1038/s41556-024-01408-9","url":null,"abstract":"Transcription factors (TFs) and cis-regulatory elements (CREs) drive organism development. Suboptimal binding of TFs to CREs is shown to be key for the specificity of gene expression. New work now indicates that a similar principle governs the activities of TFs and their regulatory specificity.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141538204","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 : 2024-07-05DOI: 10.1038/s41556-024-01411-0
Julian Naderi, Alexandre P. Magalhaes, Gözde Kibar, Gregoire Stik, Yaotian Zhang, Sebastian D. Mackowiak, Hannah M. Wieler, Francesca Rossi, Rene Buschow, Marie Christou-Kent, Marc Alcoverro-Bertran, Thomas Graf, Martin Vingron, Denes Hnisz
Transcription factors (TFs) control specificity and activity of gene transcription, but whether a relationship between these two features exists is unclear. Here we provide evidence for an evolutionary trade-off between the activity and specificity in human TFs encoded as submaximal dispersion of aromatic residues in their intrinsically disordered protein regions. We identified approximately 500 human TFs that encode short periodic blocks of aromatic residues in their intrinsically disordered regions, resembling imperfect prion-like sequences. Mutation of periodic aromatic residues reduced transcriptional activity, whereas increasing the aromatic dispersion of multiple human TFs enhanced transcriptional activity and reprogramming efficiency, promoted liquid–liquid phase separation in vitro and more promiscuous DNA binding in cells. Together with recent work on enhancer elements, these results suggest an important evolutionary role of suboptimal features in transcriptional control. We propose that rational engineering of amino acid features that alter phase separation may be a strategy to optimize TF-dependent processes, including cellular reprogramming. Naderi et al. show that increasing the dispersion of aromatic residues in intrinsically disordered regions of human transcription factors enhances their activity but reduces their specificity.
{"title":"An activity-specificity trade-off encoded in human transcription factors","authors":"Julian Naderi, Alexandre P. Magalhaes, Gözde Kibar, Gregoire Stik, Yaotian Zhang, Sebastian D. Mackowiak, Hannah M. Wieler, Francesca Rossi, Rene Buschow, Marie Christou-Kent, Marc Alcoverro-Bertran, Thomas Graf, Martin Vingron, Denes Hnisz","doi":"10.1038/s41556-024-01411-0","DOIUrl":"10.1038/s41556-024-01411-0","url":null,"abstract":"Transcription factors (TFs) control specificity and activity of gene transcription, but whether a relationship between these two features exists is unclear. Here we provide evidence for an evolutionary trade-off between the activity and specificity in human TFs encoded as submaximal dispersion of aromatic residues in their intrinsically disordered protein regions. We identified approximately 500 human TFs that encode short periodic blocks of aromatic residues in their intrinsically disordered regions, resembling imperfect prion-like sequences. Mutation of periodic aromatic residues reduced transcriptional activity, whereas increasing the aromatic dispersion of multiple human TFs enhanced transcriptional activity and reprogramming efficiency, promoted liquid–liquid phase separation in vitro and more promiscuous DNA binding in cells. Together with recent work on enhancer elements, these results suggest an important evolutionary role of suboptimal features in transcriptional control. We propose that rational engineering of amino acid features that alter phase separation may be a strategy to optimize TF-dependent processes, including cellular reprogramming. Naderi et al. show that increasing the dispersion of aromatic residues in intrinsically disordered regions of human transcription factors enhances their activity but reduces their specificity.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41556-024-01411-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141538202","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 : 2024-07-05DOI: 10.1038/s41556-024-01457-0
Julia A. Zimmermann, Kerstin Lucht, Manuel Stecher, Chahat Badhan, Katharina M. Glaser, Maximilian W. Epple, Lena R. Koch, Ward Deboutte, Thomas Manke, Klaus Ebnet, Frauke Brinkmann, Olesja Fehler, Thomas Vogl, Ev-Marie Schuster, Anna Bremser, Joerg M. Buescher, Angelika S. Rambold
Eukaryotic cells contain several membrane-separated organelles to compartmentalize distinct metabolic reactions. However, it has remained unclear how these organelle systems are coordinated when cells adapt metabolic pathways to support their development, survival or effector functions. Here we present OrgaPlexing, a multi-spectral organelle imaging approach for the comprehensive mapping of six key metabolic organelles and their interactions. We use this analysis on macrophages, immune cells that undergo rapid metabolic switches upon sensing bacterial and inflammatory stimuli. Our results identify lipid droplets (LDs) as primary inflammatory responder organelle, which forms three- and four-way interactions with other organelles. While clusters with endoplasmic reticulum (ER) and mitochondria (mitochondria–ER–LD unit) help supply fatty acids for LD growth, the additional recruitment of peroxisomes (mitochondria–ER–peroxisome–LD unit) supports fatty acid efflux from LDs. Interference with individual components of these units has direct functional consequences for inflammatory lipid mediator synthesis. Together, we show that macrophages form functional multi-organellar units to support metabolic adaptation and provide an experimental strategy to identify organelle-metabolic signalling hubs. Zimmermann et al. present OrgaPlexing, an imaging pipeline mapping metabolic organelles and their interactions. They find changes in mitochondria, ER, peroxisome and lipid droplet dynamics that impact macrophage inflammatory lipid mediator synthesis.
{"title":"Functional multi-organelle units control inflammatory lipid metabolism of macrophages","authors":"Julia A. Zimmermann, Kerstin Lucht, Manuel Stecher, Chahat Badhan, Katharina M. Glaser, Maximilian W. Epple, Lena R. Koch, Ward Deboutte, Thomas Manke, Klaus Ebnet, Frauke Brinkmann, Olesja Fehler, Thomas Vogl, Ev-Marie Schuster, Anna Bremser, Joerg M. Buescher, Angelika S. Rambold","doi":"10.1038/s41556-024-01457-0","DOIUrl":"10.1038/s41556-024-01457-0","url":null,"abstract":"Eukaryotic cells contain several membrane-separated organelles to compartmentalize distinct metabolic reactions. However, it has remained unclear how these organelle systems are coordinated when cells adapt metabolic pathways to support their development, survival or effector functions. Here we present OrgaPlexing, a multi-spectral organelle imaging approach for the comprehensive mapping of six key metabolic organelles and their interactions. We use this analysis on macrophages, immune cells that undergo rapid metabolic switches upon sensing bacterial and inflammatory stimuli. Our results identify lipid droplets (LDs) as primary inflammatory responder organelle, which forms three- and four-way interactions with other organelles. While clusters with endoplasmic reticulum (ER) and mitochondria (mitochondria–ER–LD unit) help supply fatty acids for LD growth, the additional recruitment of peroxisomes (mitochondria–ER–peroxisome–LD unit) supports fatty acid efflux from LDs. Interference with individual components of these units has direct functional consequences for inflammatory lipid mediator synthesis. Together, we show that macrophages form functional multi-organellar units to support metabolic adaptation and provide an experimental strategy to identify organelle-metabolic signalling hubs. Zimmermann et al. present OrgaPlexing, an imaging pipeline mapping metabolic organelles and their interactions. They find changes in mitochondria, ER, peroxisome and lipid droplet dynamics that impact macrophage inflammatory lipid mediator synthesis.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41556-024-01457-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141538205","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 : 2024-07-04DOI: 10.1038/s41556-024-01452-5
Ruoyu Chen, William Stainier, Jeremy Dufourt, Mounia Lagha, Ruth Lehmann
Biomolecular condensates organize biochemical processes at the subcellular level and can provide spatiotemporal regulation within a cell. Among these, ribonucleoprotein (RNP) granules are storage hubs for translationally repressed mRNA. Whether RNP granules can also activate translation and how this could be achieved remains unclear. Here, using single-molecule imaging, we demonstrate that the germ cell-determining RNP granules in Drosophila embryos are sites for active translation of nanos mRNA. Nanos translation occurs preferentially at the germ granule surface with the 3′ UTR buried within the granule. Smaug, a cytosolic RNA-binding protein, represses nanos translation, which is relieved when Smaug is sequestered to the germ granule by the scaffold protein Oskar. Together, our findings uncover a molecular process by which RNP granules achieve localized protein synthesis through the compartmentalized loss of translational repression. Chen et al. perform single-molecule imaging of translation at ribonucleoprotein (RNP) granules. They show that RNP granule surfaces are sites of nanos mRNA translation, whereas the granule interior is translationally repressive.
{"title":"Direct observation of translational activation by a ribonucleoprotein granule","authors":"Ruoyu Chen, William Stainier, Jeremy Dufourt, Mounia Lagha, Ruth Lehmann","doi":"10.1038/s41556-024-01452-5","DOIUrl":"10.1038/s41556-024-01452-5","url":null,"abstract":"Biomolecular condensates organize biochemical processes at the subcellular level and can provide spatiotemporal regulation within a cell. Among these, ribonucleoprotein (RNP) granules are storage hubs for translationally repressed mRNA. Whether RNP granules can also activate translation and how this could be achieved remains unclear. Here, using single-molecule imaging, we demonstrate that the germ cell-determining RNP granules in Drosophila embryos are sites for active translation of nanos mRNA. Nanos translation occurs preferentially at the germ granule surface with the 3′ UTR buried within the granule. Smaug, a cytosolic RNA-binding protein, represses nanos translation, which is relieved when Smaug is sequestered to the germ granule by the scaffold protein Oskar. Together, our findings uncover a molecular process by which RNP granules achieve localized protein synthesis through the compartmentalized loss of translational repression. Chen et al. perform single-molecule imaging of translation at ribonucleoprotein (RNP) granules. They show that RNP granule surfaces are sites of nanos mRNA translation, whereas the granule interior is translationally repressive.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.nature.com/articles/s41556-024-01452-5.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141521578","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}
Despite the demonstrated importance of DNA G-quadruplexes (G4s) in health and disease, technologies to readily manipulate specific G4 folding for functional analysis and therapeutic purposes are lacking. Here we employ G4-stabilizing protein/ligand in conjunction with CRISPR to selectively facilitate single or multiple targeted G4 folding within specific genomic loci. We demonstrate that fusion of nucleolin with a catalytically inactive Cas9 can specifically stabilize G4s in the promoter of oncogene MYC and muscle-associated gene Itga7 as well as telomere G4s, leading to cell proliferation arrest, inhibition of myoblast differentiation and cell senescence, respectively. Furthermore, CRISPR can confer intra-G4 selectivity to G4-binding compounds pyridodicarboxamide and pyridostatin. Compared with traditional G4 ligands, CRISPR-guided biotin-conjugated pyridodicarboxamide enables a more precise investigation into the biological functionality of de novo G4s. Our study provides insights that will enhance understanding of G4 functions and therapeutic interventions. Qin, Liu and colleagues develop a tool that combines CRISPR technology with G-quadruplex (G4)-stabilizing protein or ligand to specifically target DNA G4 structures. This tool provides better understanding of G4 functions and enables G4-based drug development.
{"title":"Targeting specific DNA G-quadruplexes with CRISPR-guided G-quadruplex-binding proteins and ligands","authors":"Geng Qin, Zhenqi Liu, Jie Yang, Xiaofeng Liao, Chuanqi Zhao, Jinsong Ren, Xiaogang Qu","doi":"10.1038/s41556-024-01448-1","DOIUrl":"10.1038/s41556-024-01448-1","url":null,"abstract":"Despite the demonstrated importance of DNA G-quadruplexes (G4s) in health and disease, technologies to readily manipulate specific G4 folding for functional analysis and therapeutic purposes are lacking. Here we employ G4-stabilizing protein/ligand in conjunction with CRISPR to selectively facilitate single or multiple targeted G4 folding within specific genomic loci. We demonstrate that fusion of nucleolin with a catalytically inactive Cas9 can specifically stabilize G4s in the promoter of oncogene MYC and muscle-associated gene Itga7 as well as telomere G4s, leading to cell proliferation arrest, inhibition of myoblast differentiation and cell senescence, respectively. Furthermore, CRISPR can confer intra-G4 selectivity to G4-binding compounds pyridodicarboxamide and pyridostatin. Compared with traditional G4 ligands, CRISPR-guided biotin-conjugated pyridodicarboxamide enables a more precise investigation into the biological functionality of de novo G4s. Our study provides insights that will enhance understanding of G4 functions and therapeutic interventions. Qin, Liu and colleagues develop a tool that combines CRISPR technology with G-quadruplex (G4)-stabilizing protein or ligand to specifically target DNA G4 structures. This tool provides better understanding of G4 functions and enables G4-based drug development.","PeriodicalId":18977,"journal":{"name":"Nature Cell Biology","volume":null,"pages":null},"PeriodicalIF":17.3,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141496032","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}