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Gorlitz, F.

Publications and source records attributed to Gorlitz, F..

3 recordsLinked to original sources

A Multimodal Adaptive Optical Microscope For In Vivo Imaging from Molecules to Organisms

Understanding biological systems requires observing features and processes across vast spatial and temporal scales, spanning nanometers to centimeters and milliseconds to days, often using multiple imaging modalities within complex native microenvironments. Yet, achieving this comprehensive view is challenging because microscopes optimized for specific tasks typically lack versatility due to inherent optical and sample handling trade-offs, and frequently suffer performance degradation from sample-induced optical aberrations in multicellular contexts. Here, we present MOSAIC, a reconfigurable microscope that integrates multiple advanced imaging techniques including light-sheet, label-free, super-resolution, and multi-photon, all equipped with adaptive optics. MOSAIC enables non-invasive imaging of subcellular dynamics in both cultured cells and live multicellular organisms, nanoscale mapping of molecular architectures across millimeter-scale expanded tissues, and structural/functional neural imaging within live mice. MOSAIC facilitates correlative studies across biological scales within the same specimen, providing an integrated platform for broad biological investigation.

cell biology↗

Characterization, Comparison, and Optimization of Lattice Light Sheets

Lattice light sheet microscopy excels at the non-invasive imaging of three-dimensional (3D) dynamic processes at high spatiotemporal resolution within cells and developing embryos. Recently, several papers have called into question the performance of lattice light sheets relative to the Gaussian sheets most common in light sheet microscopy. Here we undertake a comprehensive theoretical and experimental analysis of various forms of light sheet microscopy which both demonstrates and explains why lattice light sheets provide significant improvements in resolution and photobleaching reduction. The analysis provides a procedure to select the correct light sheet for a desired experiment and specifies the processing that maximizes the use of all fluorescence generated within the light sheet excitation envelope for optimal resolution while minimizing image artifacts and photodamage. Development of a new type of "harmonic balanced" lattice light sheet is shown to improve performance at all spatial frequencies within its 3D resolution limits and maintains this performance over lengthened propagation distances allowing for expanded fields of view. Significance StatementDespite its rapidly growing use, several misconceptions remain concerning the physics of image formation and its optimization in light sheet microscopy, particularly in high resolution variants tailored for subcellular imaging. These include the role of excitation sidelobes, the significance of out-of-focus fluorescence, the importance and optimization of deconvolution, and the perceived advantages of Gaussian beams. Here we attempt to shatter these misconceptions by showing that the professed tradeoffs between axial resolution and background haze, photobleaching rate, phototoxicity, and propensity for image artifacts do not exist for well-crafted lattice light sheets whose data is acquired and processed rigorously. The framework we provide should enable others to optimize light sheets and extract the most information at the lowest cost in their experiments.

cell biology↗

The influence of peptide context on signalling and trafficking of glucagon-like peptide-1 receptor biased agonists

Signal bias and membrane trafficking have recently emerged as important considerations in the therapeutic targeting of the glucagon-like peptide-1 receptor (GLP-1R) in type 2 diabetes and obesity. In the present study, we have evaluated a peptide series with varying sequence homology between native GLP-1 and exendin-4, the archetypal ligands on which approved GLP-1R agonists are based. We find notable differences in agonist-mediated signalling, endocytosis and recycling, dependent both on the introduction of a His [->] Phe switch at position 1 and the specific mid-peptide helical regions and C-termini of the two agonists. These observations were linked to insulin secretion in a beta cell model and provide insights into how ligand factors influence GLP-1R function at the cellular level. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=84 SRC="FIGDIR/small/961524v1_ufig1.gif" ALT="Figure 1"> View larger version (25K): org.highwire.dtl.DTLVardef@cb425borg.highwire.dtl.DTLVardef@719e37org.highwire.dtl.DTLVardef@14a45b9org.highwire.dtl.DTLVardef@127afd1_HPS_FORMAT_FIGEXP M_FIG C_FIG

pharmacology and toxicology↗