Actin structure formation, membrane dynamics, and force generation during blood platelet spreading

Zelena, Anna

dc.contributor.advisor	Koester, Sarah Prof. Dr.
dc.contributor.author	Zelena, Anna
dc.date.accessioned	2023-03-17T18:28:46Z
dc.date.issued	2023-03-17
dc.identifier.uri	http://resolver.sub.uni-goettingen.de/purl?ediss-11858/14584
dc.identifier.uri	http://dx.doi.org/10.53846/goediss-9791
dc.format.extent	XXX Seiten	de
dc.language.iso	eng	de
dc.subject.ddc	530	de
dc.title	Actin structure formation, membrane dynamics, and force generation during blood platelet spreading	de
dc.type	doctoralThesis	de
dc.contributor.referee	Koester, Sarah Prof. Dr.
dc.date.examination	2022-03-22	de
dc.subject.gok	Physik (PPN621336750)	de
dc.description.abstracteng	Blood platelets are essential to the formation of blood clots and prevent uncontrolled bleeding. They are non-nucleated fragments of larger bone marrow cells known as megakaryocytes. Platelets undergo fast morphological changes during blood flow recovery when they change their shape from a discoid to a flat structure. The platelet cytoskeleton is reorganized during this process of activation and, ultimately, forms a strong adhesion bond to the extracellular matrix. In this thesis, we show two studies. The first study focuses on the investigation of single platelet in vitro by combining traction force microscopy with silicon-rhodamine actin probes in a time-resolved manner. Thus we can spatially and temporally correlate the force generation with the emerging acting structures. Additionally, we test this mechanism for different thrombin concentrations for platelet activation as well as different fibrinogen coverages on the substrate. Our results show, that the local hot spots in the force fields align well with the visualized end points of fibrous actin. Besides, the force generation is a very robust mechanism independent of changes in the amount of thrombin or fibrinogen. The second study focuses on membrane adhesion in combination with metal-induced energy transfer imaging in static and rapid modes. The static MIET mode reveals three-dimensional structures of the basal membrane with areas that are particularly close to the metal substrate. The spatial distribution of these areas likely corresponds to focal adhesion spots. The rapid mode shows the temporal evolution of the membrane-to-surface distance during adhesion and spreading with nanometer resolution. In conclusion, we demonstrate that platelets are indeed very strong with a fast and robust spreading mechanism.	de
dc.contributor.coReferee	Rehfeldt, Florian Dr.
dc.subject.eng	human blood plateles	de
dc.subject.eng	Traction Force Microscopy	de
dc.subject.eng	fluorescence microscopy	de
dc.subject.eng	single cells	de
dc.subject.eng	actin	de
dc.subject.eng	Metal-induced Energy Transfer	de
dc.identifier.urn	urn:nbn:de:gbv:7-ediss-14584-0
dc.date.embargoed	2024-03-21
dc.affiliation.institute	Fakultät für Physik	de
dc.description.embargoed	2024-03-21	de
dc.identifier.ppn	1839533013
dc.notes.confirmationsent	Confirmation sent 2023-03-20T06:15:01	de