Cryo-electron microscopy is a dynamically developing method with increasing utilization in structural biology research. Recent advances in the detector technology enabled near-atomic structural studies of protein complexes including the molecular machines such as RNA polymerases or ribosomes. One advantage of the cryo-electron microscopy with respect to the other high-resolution structural biology methods lies in its capability to structurally characterize pleiomorphic objects and molecular assemblies which are difficult to characterize under in vitro conditions by cryo-electron tomography (cryo-ET). Moreover, when cryo-ET is preceeded by the focused ion beam micromachining (FIBM) of the cellular sample, the resulting cryo-ET tomograms will provide structural information about the macromolecular complexes in the context of the cells at near-native conditions.

The aim of the diploma thesis is to utilize FIBM and cryo-ET to study higher order assemblies of RNA polymerase and ribosome inside Saccharomyces cerevisiae under standard and stress conditions. The student will deepen his knowledge in molecular biology and electron microscopy. She/he will learn to operate both scanning and transmission electron microscopes and analyze the cryo-ET data.

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