Fluorescence microscopy is a widely used technique for imaging of biological structures due to its noninvasiveness although resolution of conventional fluorescence microscopes is limited to about 200-300 nm due to the diffraction limit of light. Super-resolution fluorescence microscopy offers an extension of the original method that allows optical imaging below the diffraction limit. In this thesis, a microscope for localization-based super-resolution fluorescence microscopy techniques such as

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... tochastic Optical Reconstruction Microscopy (STORM) or Photoactivated Localization Microscopy (PALM) was established. An epifluorescence microscope was built for this purpose that provides both widefield and Total Internal Reflection Fluorescence (TIRF) excitation modalities and focus was put on the special requirements of localization-based super-resolution methods. This included a high mechanical and optical stability realized by a compact design and implementation of a home-built perfect focus system. The setup was further designed to allow both two- and three-dimensional imaging. The work also included both the development of a setup control software and a software for the analysis of the required data. Different analysis methods and parameters were tested on simulated data before the performance of the microscope was demonstrated in two and three dimensions at appropriate test samples such as the cellular microtubule network. These experiments showed the capability of super-resolution microscopy to reveal underlying structures that cannot be resolved by conventional fluorescence microscopy. Resolutions could be achieved down to approximately 30 nm in the lateral and 115 nm in the axial dimension. Subsequently, the established method was applied to two biological systems. The first is a study of the budding of the human immunodeficiency virus type 1 (HIV-1) from the host cell. In this step of the viral reproduction cycle, the virus hijacks the cellular endosomal sorting complex required for transport (ESCRT) machinery [...]