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    A guide to super-resolution fluorescence microscopy
    (New York, NY : Rockefeller Univ. Press, 2010) Schermelleh, L.; Heintzmann, R.; Leonhardt, H.
    For centuries, cell biology has been based on light microscopy and at the same time been limited by its optical resolution. However, several new technologies have been developed recently that bypass this limit. These new super-resolution technologies are either based on tailored illumination, nonlinear fluorophore responses, or the precise localization of single molecules. Overall, these new approaches have created unprecedented new possibilities to investigate the structure and function of cells. © 2010 Schermelleh et al.
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    Vinculin binding angle in podosomes revealed by high resolution microscopy
    (San Francisco, CA : Public Library of Science, 2014) Walde, M.; Monypenny, J.; Heintzmann, R.; Jones, G.E.; Cox, S.
    Podosomes are highly dynamic actin-rich adhesive structures formed predominantly by cells of the monocytic lineage, which degrade the extracellular matrix. They consist of a core of F-actin and actin-regulating proteins, surrounded by a ring of adhesion-associated proteins such as vinculin. We have characterised the structure of podosomes in macrophages, particularly the structure of the ring, using three super-resolution fluorescence microscopy techniques: stimulated emission depletion microscopy, structured illumination microscopy and localisation microscopy. Rather than being round, as previously assumed, we found the vinculin ring to be created from relatively straight strands of vinculin, resulting in a distinctly polygonal shape. The strands bind preferentially at angles between 116° and 135°. Furthermore, adjacent vinculin strands are observed nucleating at the corners of the podosomes, suggesting a mechanism for podosome growth.
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    Optical photon reassignment microscopy (OPRA)
    (Heidelberg [u.a.] : Springer Open, 2013) Roth, S.; Sheppard, C.J.R.; Wicker, K.; Heintzmann, R.
    To enhance the resolution of a confocal laser scanning microscope the additional information of a pinhole plane image taken at every excitation scan position can be used (Sheppard 1988). This photon reassignment principle is based on the fact that the most probable position of an emitter is at half way between the nominal focus of the excitation laser and the position corresponding to the (off centre) detection position. Therefore, by reassigning the detected photons to this place, an image with enhanced detection efficiency and resolution is obtained. Here we present optical photon reassignment microscopy (OPRA) which realizes this concept in an all-optical way obviating the need for image-processing. With the help of an additional intermediate optical beam expansion between descanning and a further rescanning of the detected light, an image with the advantages of photon reassignment can be acquired. However, just as in computational photon reassignment, a loss in confocal sectioning performance is caused by working with relatively open pinholes. The OPRA system shares properties such as flexibility and ease of use with a confocal laser scanning microscope, and is therefore expected to be of use for future biomedical routine research.