TY - DATA AB - 3D-reconstruction of living brain tissue down to individual synapse level would create opportunities for decoding the dynamics and structure-function relationships of the brain’s complex and dense information processing network. However, it has been hindered by insufficient 3D-resolution, inadequate signal-to-noise-ratio, and prohibitive light burden in optical imaging, whereas electron microscopy is inherently static. Here we solved these challenges by developing an integrated optical/machine learning technology, LIONESS (Live Information-Optimized Nanoscopy Enabling Saturated Segmentation). It leverages optical modifications to stimulated emission depletion (STED) microscopy in comprehensively, extracellularly labelled tissue and prior information on sample structure via machine learning to simultaneously achieve isotropic super-resolution, high signal-to-noise-ratio, and compatibility with living tissue. This allows dense deep-learning-based instance segmentation and 3D-reconstruction at synapse level incorporating molecular, activity, and morphodynamic information. LIONESS opens up avenues for studying the dynamic functional (nano-)architecture of living brain tissue. AU - Danzl, Johann G ID - 12817 TI - Research data for the publication "Dense 4D nanoscale reconstruction of living brain tissue" ER - TY - DATA AB - Aromatic side chains are important reporters of the plasticity of proteins, and often form important contacts in protein–protein interactions. We studied aromatic residues in the two structurally homologous cross-β amyloid fibrils HET-s, and HELLF by employing a specific isotope-labeling approach and magic-angle-spinning NMR. The dynamic behavior of the aromatic residues Phe and Tyr indicates that the hydrophobic amyloid core is rigid, without any sign of "breathing motions" over hundreds of milliseconds at least. Aromatic residues exposed at the fibril surface have a rigid ring axis but undergo ring flips on a variety of time scales from nanoseconds to microseconds. Our approach provides direct insight into hydrophobic-core motions, enabling a better evaluation of the conformational heterogeneity generated from an NMR structural ensemble of such amyloid cross-β architecture. AU - Becker, Lea Marie AU - Schanda, Paul ID - 12497 KW - aromatic side chains KW - isotopic labeling KW - protein dynamics KW - ring flips KW - spin relaxation TI - Research data to: The rigid core and flexible surface of amyloid fibrils probed by magic-angle-spinning NMR spectroscopy of aromatic residues ER - TY - DATA AB - Mapping the complex and dense arrangement of cells and their connectivity in brain tissue demands nanoscale spatial resolution imaging. Super-resolution optical microscopy excels at visualizing specific molecules and individual cells but fails to provide tissue context. Here, we developed Comprehensive Analysis of Tissues across Scales (CATS), a technology to densely map brain tissue architecture from millimeter regional to nanometer synaptic scales in diverse chemically fixed brain preparations, including rodent and human. CATS uses fixation-compatible extracellular labeling and optical imaging, including stimulated emission depletion or expansion microscopy, to comprehensively delineate cellular structures. It enables three-dimensional reconstruction of single synapses and mapping of synaptic connectivity by identification and analysis of putative synaptic cleft regions. Applying CATS to the mouse hippocampal mossy fiber circuitry, we reconstructed and quantified the synaptic input and output structure of identified neurons. We furthermore demonstrate applicability to clinically derived human tissue samples, including formalin-fixed paraffin-embedded routine diagnostic specimens, for visualizing the cellular architecture of brain tissue in health and disease. AU - Danzl, Johann G ID - 13126 TI - Research data for the publication "Imaging brain tissue architecture across millimeter to nanometer scales" ER - TY - DATA AB - The emergence of large-scale order in self-organized systems relies on local interactions between individual components. During bacterial cell division, FtsZ -- a prokaryotic homologue of the eukaryotic protein tubulin -- polymerizes into treadmilling filaments that further organize into a cytoskeletal ring. In vitro, FtsZ filaments can form dynamic chiral assemblies. However, how the active and passive properties of individual filaments relate to these large-scale self-organized structures remains poorly understood. Here, we connect single filament properties with the mesoscopic scale by combining minimal active matter simulations and biochemical reconstitution experiments. We show that density and flexibility of active chiral filaments define their global order. At intermediate densities, curved, flexible filaments organize into chiral rings and polar bands. An effectively nematic organization dominates for high densities and for straight, mutant filaments with increased rigidity. Our predicted phase diagram captures these features quantitatively, demonstrating how the flexibility, density and chirality of active filaments affect their collective behaviour. Our findings shed light on the fundamental properties of active chiral matter and explain how treadmilling FtsZ filaments organize during bacterial cell division. AU - Dunajova, Zuzana AU - Prats Mateu, Batirtze AU - Radler, Philipp AU - Lim, Keesiang AU - Brandis, Dörte AU - Velicky, Philipp AU - Danzl, Johann G AU - Wong, Richard W. AU - Elgeti, Jens AU - Hannezo, Edouard B AU - Loose, Martin ID - 13116 TI - Chiral and nematic phases of flexible active filaments ER - TY - DATA AB - Many insects carry an ancient X chromosome—the Drosophila Muller element F—that likely predates their origin. Interestingly, the X has undergone turnover in multiple fly species (Diptera) after being conserved for more than 450 My. The long evolutionary distance between Diptera and other sequenced insect clades makes it difficult to infer what could have contributed to this sudden increase in rate of turnover. Here, we produce the first genome and transcriptome of scorpionflies (genus Panorpa), an insect belonging to a long overlooked sister-order to Diptera: Mecoptera. Combining our genome assembly with genomic short-read data, we obtain genome coverage and identify X-linked super-scaffolds. We further perform a gene homology analysis between the Panorpa X and a closely related Diptera species, and we assess the conservation of the Panorpa X-linked gene content with that of more distantly related insect species. We explored the structure of the Panorpa X by determining its repeat content, GC content, and nucleotide diversity. Finally, we used RNAseq data to detect the presence of dosage compensation in somatic tissues, as well as to explore gene expression tissue-specificity, and sex-bias in gene expression. We find high conservation of gene content between the mecopteran X and the dipteran Muller F element, as well as several shared biological features, such as the presence of dosage compensation and a low amount of genetic diversity, consistent with a low recombination rate. However, the 2 homologous X chromosomes differ strikingly in their size and number of genes they carry. Our results therefore support a common ancestry of the mecopteran and ancestral dipteran X chromosomes, and suggest that Muller element F shrank in size and gene content after the split of Diptera and Mecoptera, which may have contributed to its turnover in dipteran insects. AU - Lasne, Clementine AU - Elkrewi, Marwan N ID - 14614 KW - Panorpa KW - scorpionfly KW - genome KW - transcriptome TI - The scorpionfly (Panorpa cognata) genome highlights conserved and derived features of the peculiar dipteran X chromosome ER - TY - DATA AB - GABAB receptor (GBR) activation inhibits neurotransmitter release in axon terminals in the brain, except in medial habenula (MHb) terminals, which show robust potentiation. However, mechanisms underlying this enigmatic potentiation remain elusive. Here, we report that GBR activation on MHb terminals induces an activity-dependent transition from a facilitating, tonic to a depressing, phasic neurotransmitter release mode. This transition is accompanied by a 4.1-fold increase in readily releasable vesicle pool (RRP) size and a 3.5-fold increase of docked synaptic vesicles at the presynaptic active zone (AZ). Strikingly, tonic and phasic release exhibit distinct coupling distances and are selectively affected by deletion of synaptoporin (SPO) and Ca2+-dependent activator protein for secretion 2 (CAPS2), respectively. SPO modulates augmentation, the short-term plasticity associated with tonic release, and CAPS2 retains the increased RRP for initial responses in phasic response trains. Double pre-embedding immunolabeling confirmed the co-localization of CAPS2 and SPO inside the same terminal. The cytosolic protein CAPS2 showed a synaptic vesicle (SV)-associated distribution similar to the vesicular transmembrane protein SPO. A newly developed “Flash and Freeze-fracture” method revealed the release of SPO-associated vesicles in both tonic and phasic modes and activity-dependent recruitment of CAPS2 to the AZ during phasic release, which lasted several minutes. Overall, these results indicate that GBR activation translocates CAPS2 to the AZ along with the fusion of CAPS2-associated SVs, contributing to a persistent RRP increase. Thus, we discovered structural and molecular mechanisms underlying tonic and phasic neurotransmitter release and their transition by GBR activation in MHb terminals. AU - Shigemoto, Ryuichi ID - 13173 KW - medial habenula KW - GABAB receptor KW - vesicle release KW - Flash and Freeze KW - Flash and Freeze-fracture TI - Transition from tonic to phasic neurotransmitter release by presynaptic GABAB receptor activation in medial habenula terminals ER - TY - DATA AB - FtsA is crucial for assembly of the E. coli divisome, as it dynamically links cytoplasmic FtsZ filaments with transmembrane cell division proteins. FtsA allegedly initiates cell division by switching from an inactive polymeric to an active monomeric confirmation, which recruits downstream proteins and stabilizes FtsZ filaments. Here, we use biochemical reconstitution experiments combined with quantitative fluorescence microscopy to study divisome activation in vitro. We compare wildtype-FtsA with FtsA-R286W, a constantly active gain-of-function mutant and find that R286W outperforms the wildtype protein in replicating FtsZ treadmilling dynamics, stabilizing FtsZ filaments and recruiting FtsN. We attribute these differences to a faster membrane exchange of FtsA-R286W and its higher packing density below FtsZ filaments. Using FRET microscopy, we find that FtsN binding does not compete with, but promotes FtsA self-interaction. Our findings suggest a model where FtsA always forms dynamic polymers on the membrane, which re-organize during assembly and activation of the divisome. AU - Radler, Philipp ID - 10934 KW - Bacterial cell division KW - in vitro reconstitution KW - FtsZ KW - FtsN KW - FtsA TI - In vitro reconstitution of Escherichia coli divisome activation ER - TY - DATA AU - Schulz, Rouven ID - 11542 TI - Source Data (Chimeric GPCRs mimic distinct signaling pathways and modulate microglia responses) ER - TY - DATA AB - This .zip File contains the transport data, the codes for the data analysis, the microscopy analysis and the codes for the theoretical simulations for "Majorana-like Coulomb spectroscopy in the absence of zero bias peaks" by M. Valentini, et. al. The transport data are saved with hdf5 file format. The files can be open with the log browser of Labber. AU - Valentini, Marco AU - San-Jose, Pablo AU - Arbiol, Jordi AU - Marti-Sanchez, Sara AU - Botifoll, Marc ID - 12522 TI - Data for "Majorana-like Coulomb spectroscopy in the absence of zero bias peaks" ER - TY - DATA AB - Here are the research data underlying the publication "Effects of fine-scale population structure on the distribution of heterozygosity in a long-term study of Antirrhinum majus" Further information are summed up in the README document. AU - Surendranadh, Parvathy AU - Arathoon, Louise S AU - Baskett, Carina AU - Field, David AU - Pickup, Melinda AU - Barton, Nicholas H ID - 11321 TI - Effects of fine-scale population structure on the distribution of heterozygosity in a long-term study of Antirrhinum majus ER -