Dokument: From ultrastructure to near-atomic resolution: cryo-EM studies of the core molecular machineries of selective autophagy and protein biosynthesis
| Titel: | From ultrastructure to near-atomic resolution: cryo-EM studies of the core molecular machineries of selective autophagy and protein biosynthesis | |||||||
| URL für Lesezeichen: | https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=66401 | |||||||
| URN (NBN): | urn:nbn:de:hbz:061-20250813-091109-8 | |||||||
| Kollektion: | Dissertationen | |||||||
| Sprache: | Englisch | |||||||
| Dokumententyp: | Wissenschaftliche Abschlussarbeiten » Dissertation | |||||||
| Medientyp: | Text | |||||||
| Autor: | Jungbluth, Lisa [Autor] | |||||||
| Dateien: |
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| Beitragende: | Prof. Dr. Sachse, Carsten [Gutachter] Prof. Dr. Schroeder, Gunnar [Gutachter] | |||||||
| Stichwörter: | cryo-EM, autophagy, C. glutamicum, 70S | |||||||
| Dewey Dezimal-Klassifikation: | 500 Naturwissenschaften und Mathematik » 570 Biowissenschaften; Biologie | |||||||
| Beschreibung: | The different techniques in cryogenic electron microscopy can span resolution ranges
from an ultrastructural scale to near-atomic resolution and are therefore suitable to investigate cellular processes including autophagy and protein biosynthesis. Autophagy directs the degradation of cargos with varying sizes from a single protein chain by chaperone-mediated autophagy up to whole organelles in (selective) macroautophagy. In this thesis, the selective degradation of ribosomes via NUFIP1 as well as the ultrastructural function of the selective autophagy receptor p62 were investigated with cryogenic electron microscopy. To understand the underlying molecular mechanism of NUFIP1-mediated ribophagy, NUFIP1 was studied in the context of different autophagy induced conditions by single-particle analysis of 80S human ribosomes. To study the interaction- between p62 and a phagophore membrane, cryogenic electron tomography was employed on samples of LC3 covered liposomes together with p62. Moreover, to investigate the higher-order structure of cellular p62 bodies and associated cargo, phase separation droplets of p62 filaments were formed by the addition of polyubiquitinated cargo and imaged using cryogenic electron tomography. To complete the available resolution range of cryogenic electron microscopy, the unique features of the Actinobacterium Corynebacterium glutamicum 70S ribosome were investigated by single-particle analysis. The contribution of bS22 to the ribosomal function in C. glutamicum was determined by solving the threedimensional structures of the wildtype and ΔbS22 ribosome to near-atomic resolution. By exploiting the potential of single-particle analysis in the structural analysis of dynamic processes, 70S ribosomes were captured in four distinct translational states. In addition, the mode of action of Kasugamycin on the 70S ribosome was studied. The binding pocket of Kasugamycin within the 70S ribosomes could be identified and its modulation on the translational landscape for the wildtype and two resistant mutants resolved. The different results generated in this thesis demonstrate the capabilities of cryogenic electron microscopy to resolve high-resolution atomic-level detail in the case of a bacterial ribosome up to the ultrastructure of molecular assemblies for the selective autophagy receptor p62. | |||||||
| Lizenz: |  Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz | |||||||
| Fachbereich / Einrichtung: | Mathematisch- Naturwissenschaftliche Fakultät » WE Biologie | |||||||
| Dokument erstellt am: | 13.08.2025 | |||||||
| Dateien geändert am: | 13.08.2025 | |||||||
| Promotionsantrag am: | 29.05.2024 | |||||||
| Datum der Promotion: | 09.07.2024 |
