Urban, Nicolai T.

[["dc.bibliographiccitation.artnumber","7368"],["dc.bibliographiccitation.firstpage","204"],["dc.bibliographiccitation.journal","Nature"],["dc.bibliographiccitation.lastpage","208"],["dc.bibliographiccitation.volume","478"],["dc.contributor.author","Grotjohann, Tim"],["dc.contributor.author","Testa, Ilaria"],["dc.contributor.author","Leutenegger, Marcel"],["dc.contributor.author","Bock, Hannes"],["dc.contributor.author","Urban, Nicolai T."],["dc.contributor.author","Lavoie-Cardinal, Flavie"],["dc.contributor.author","Willig, Katrin I."],["dc.contributor.author","Eggeling, Christian"],["dc.contributor.author","Jakobs, Stefan"],["dc.contributor.author","Hell, Stefan W."],["dc.date.accessioned","2017-09-07T11:43:21Z"],["dc.date.available","2017-09-07T11:43:21Z"],["dc.date.issued","2011"],["dc.description.abstract","Lens-based optical microscopy failed to discern fluorescent features closer than 200 nm for decades, but the recent breaking of the diffraction resolution barrier by sequentially switching the fluorescence capability of adjacent features on and off is making nanoscale imaging routine. Reported fluorescence nanoscopy variants switch these features either with intense beams at defined positions or randomly, molecule by molecule. Here we demonstrate an optical nanoscopy that records raw data images from living cells and tissues with low levels of light. This advance has been facilitated by the generation of reversibly switchable enhanced green fluorescent protein (rsEGFP), a fluorescent protein that can be reversibly photoswitched more than a thousand times. Distributions of functional rsEGFP-fusion proteins in living bacteria and mammalian cells are imaged at <40-nanometre resolution. Dendritic spines in living brain slices are super-resolved with about a million times lower light intensities than before. The reversible switching also enables all-optical writing of features with subdiffraction size and spacings, which can be used for data storage."],["dc.identifier.doi","10.1038/nature10497"],["dc.identifier.gro","3142644"],["dc.identifier.isi","000295782800041"],["dc.identifier.pmid","21909116"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/71"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0028-0836"],["dc.title","Diffraction-unlimited all-optical imaging and writing with a photochromic GFP"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","290"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Nature Communications"],["dc.bibliographiccitation.volume","9"],["dc.contributor.author","Neef, Jakob"],["dc.contributor.author","Urban, Nicolai T."],["dc.contributor.author","Ohn, Tzu-Lun"],["dc.contributor.author","Frank, Thomas"],["dc.contributor.author","Jean, Philippe"],["dc.contributor.author","Hell, Stefan W."],["dc.contributor.author","Willig, Katrin I."],["dc.contributor.author","Moser, Tobias"],["dc.date.accessioned","2018-04-23T11:48:23Z"],["dc.date.available","2018-04-23T11:48:23Z"],["dc.date.issued","2018"],["dc.description.abstract","Ca2+ influx triggers the release of synaptic vesicles at the presynaptic active zone (AZ). A quantitative characterization of presynaptic Ca2+ signaling is critical for understanding synaptic transmission. However, this has remained challenging to establish at the required resolution. Here, we employ confocal and stimulated emission depletion (STED) microscopy to quantify the number (20–330) and arrangement (mostly linear 70 nm × 100–600 nm clusters) of Ca2+ channels at AZs of mouse cochlear inner hair cells (IHCs). Establishing STED Ca2+ imaging, we analyze presynaptic Ca2+ signals at the nanometer scale and find confined elongated Ca2+ domains at normal IHC AZs, whereas Ca2+ domains are spatially spread out at the AZs of bassoon-deficient IHCs. Performing 2D-STED fluorescence lifetime analysis, we arrive at estimates of the Ca2+ concentrations at stimulated IHC AZs of on average 25 µM. We propose that IHCs form bassoon-dependent presynaptic Ca2+-channel clusters of similar density but scalable length, thereby varying the number of Ca2+ channels amongst individual AZs."],["dc.identifier.doi","10.1038/s41467-017-02612-y"],["dc.identifier.gro","3142361"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15588"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/13498"],["dc.language.iso","en"],["dc.notes.intern","lifescience updates Crossref Import"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.relation.issn","2041-1723"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.title","Quantitative optical nanophysiology of Ca2+ signaling at inner hair cell active zones"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","no"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","992"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Neuron"],["dc.bibliographiccitation.lastpage","1000"],["dc.bibliographiccitation.volume","75"],["dc.contributor.author","Testa, Ilaria"],["dc.contributor.author","Urban, Nicolai T."],["dc.contributor.author","Jakobs, Stefan"],["dc.contributor.author","Eggeling, Christian"],["dc.contributor.author","Willig, Katrin I."],["dc.contributor.author","Hell, Stefan"],["dc.date.accessioned","2017-09-07T11:48:25Z"],["dc.date.available","2017-09-07T11:48:25Z"],["dc.date.issued","2012"],["dc.description.abstract","Lens-based fluorescence microscopy, which has long been limited in resolution to about 200 nanometers by diffraction, is rapidly evolving into a nanoscale imaging technique. Here, we show that the superresolution fluorescence microscopy called RESOLFT enables comparatively fast and continuous imaging of sensitive, nanosized features in living brain tissue. Using low-intensity illumination to switch photochromic fluorescent proteins reversibly between a fluorescent and a nonfluorescent state, we increased the resolution more than 3-fold over that of confocal microscopy in all dimensions. Dendritic spines located 10-50 mu m deep inside living organotypic hippocampal brain slices were recorded for hours without signs of degradation. Using a fast-switching protein increased the imaging speed 50-fold over reported RESOLFT schemes, which in turn enabled the recording of spontaneous and stimulated changes of dendritic actin filaments and spine morphology occurring on time scales from seconds to hours."],["dc.identifier.doi","10.1016/j.neuron.2012.07.028"],["dc.identifier.gro","3142464"],["dc.identifier.isi","000309198900011"],["dc.identifier.pmid","22998868"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/8574"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.publisher","Cell Press"],["dc.relation.issn","0896-6273"],["dc.title","Nanoscopy of Living Brain Slices with Low Light Levels"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","534a"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.volume","104"],["dc.contributor.author","Testa, Ilaria"],["dc.contributor.author","Urban, Nicolai"],["dc.contributor.author","Willig, Katrin"],["dc.contributor.author","Hell, Stefan"],["dc.date.accessioned","2022-03-01T11:44:56Z"],["dc.date.available","2022-03-01T11:44:56Z"],["dc.date.issued","2013"],["dc.identifier.doi","10.1016/j.bpj.2012.11.2958"],["dc.identifier.pii","S000634951204204X"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/103168"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-531"],["dc.relation.issn","0006-3495"],["dc.title","Resolft Nanoscopy in Life Sciences: Unraveling Fine Details with Low Light Levels"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","577"],["dc.bibliographiccitation.firstpage","1"],["dc.bibliographiccitation.journal","Nature communications"],["dc.bibliographiccitation.lastpage","9"],["dc.bibliographiccitation.volume","8"],["dc.contributor.author","Richardson, Douglas S."],["dc.contributor.author","Gregor, Carola"],["dc.contributor.author","Winter, Franziska R."],["dc.contributor.author","Urban, Nicolai T."],["dc.contributor.author","Sahl, Steffen J."],["dc.contributor.author","Willig, Katrin I."],["dc.contributor.author","Hell, Stefan W."],["dc.date.accessioned","2018-01-17T13:31:10Z"],["dc.date.available","2018-01-17T13:31:10Z"],["dc.date.issued","2017"],["dc.description.abstract","Fluorescence-based biosensors have become essential tools for modern biology, allowing real-time monitoring of biological processes within living cells. Intracellular fluorescent pH probes comprise one of the most widely used families of biosensors in microscopy. One key application of pH probes has been to monitor the acidification of vesicles during endocytosis, an essential function that aids in cargo sorting and degradation. Prior to the development of super-resolution fluorescence microscopy (nanoscopy), investigation of endosomal dynamics in live cells remained difficult as these structures lie at or below the ~250 nm diffraction limit of light microscopy. Therefore, to aid in investigations of pH dynamics during endocytosis at the nanoscale, we have specifically designed a family of ratiometric endosomal pH probes for use in live-cell STED nanoscopy.Ratiometric fluorescent pH probes are useful tools to monitor acidification of vesicles during endocytosis, but the size of vesicles is below the diffraction limit. Here the authors develop a family of ratiometric pH sensors for use in STED super-resolution microscopy, and optimize their delivery to endosomes."],["dc.identifier.doi","10.1038/s41467-017-00606-4"],["dc.identifier.pmid","28924139"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/16496"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/11717"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.notes.status","final"],["dc.relation.eissn","2041-1723"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0"],["dc.title","SRpHi ratiometric pH biosensors for super-resolution microscopy"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1277"],["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","Biophysical Journal"],["dc.bibliographiccitation.lastpage","1284"],["dc.bibliographiccitation.volume","101"],["dc.contributor.author","Urban, Nicolai T."],["dc.contributor.author","Willig, Katrin I."],["dc.contributor.author","Hell, Stefan"],["dc.contributor.author","Nägerl, U. Valentin"],["dc.date.accessioned","2017-09-07T11:43:24Z"],["dc.date.available","2017-09-07T11:43:24Z"],["dc.date.issued","2011"],["dc.description.abstract","It is difficult to investigate the mechanisms that mediate long-term changes in synapse function because synapses are small and deeply embedded inside brain tissue. Although recent fluorescence nanoscopy techniques afford improved resolution, they have so far been restricted to dissociated cells or tissue surfaces. However, to study synapses under realistic conditions, one must image several cell layers deep inside more-intact, three-dimensional preparations that exhibit strong light scattering, such as brain slices or brains in vivo. Using aberration-reducing optics, we demonstrate that it is possible to achieve stimulated emission depletion superresolution imaging deep inside scattering biological tissue. To illustrate the power of this novel (to our knowledge) approach, we resolved distinct distributions of actin inside dendrites and spines with a resolution of 60-80 nm in living organotypic brain slices at depths up to 120 Am. In addition, time-lapse stimulated emission depletion imaging revealed changes in actin-based structures inside spines and spine necks, and showed that these dynamics can be modulated by neuronal activity. Our approach greatly facilitates investigations of actin dynamics at the nanoscale within functionally intact brain tissue."],["dc.identifier.doi","10.1016/j.bpj.2011.07.027"],["dc.identifier.gro","3142670"],["dc.identifier.isi","000294653800030"],["dc.identifier.pmid","21889466"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/99"],["dc.language.iso","en"],["dc.notes.intern","WoS Import 2017-03-10"],["dc.notes.status","final"],["dc.notes.submitter","PUB_WoS_Import"],["dc.relation.issn","0006-3495"],["dc.title","STED Nanoscopy of Actin Dynamics in Synapses Deep Inside Living Brain Slices"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original"],["dspace.entity.type","Publication"]]