Publications by authors named "Karin Gries"
Article Synopsis
- VIPP1 is a crucial protein for the formation and maintenance of thylakoid membranes in plastids, and is part of the ESCRT-III superfamily, which aids in membrane deformation.
- Cryo-electron microscopy has shown that VIPP1 can form complex structures like helical rods and rings, but its specific interaction with membranes is still not well understood.
- Using high-speed atomic force microscopy, this study has revealed that VIPP1 assembles into spirals and polygons on lipid bilayers, undergoing a transformation from Archimedean to logarithmic spirals through a process of polymerization and strand annealing.
Structural features of chloroplast trigger factor determined at 2.6 Å resolution.
Acta Crystallogr D Struct Biol
October 2022
The folding of newly synthesized polypeptides requires the coordinated action of molecular chaperones. Prokaryotic cells and the chloroplasts of plant cells possess the ribosome-associated chaperone trigger factor, which binds nascent polypeptides at their exit stage from the ribosomal tunnel. The structure of bacterial trigger factor has been well characterized and it has a dragon-shaped conformation, with flexible domains responsible for ribosome binding, peptidyl-prolyl cis-trans isomerization (PPIase) activity and substrate protein binding.
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- VIPP1 is a crucial protein in cyanobacteria that helps create and maintain thylakoid membranes, which are essential for photosynthesis.
- Researchers used cryo-electron microscopy to analyze the structure of VIPP1, revealing how its flexible monomers form ring-like structures that aid in membrane binding and curvature.
- Mutations in VIPP1 lead to issues with thylakoid stability under stress, highlighting its important role in protecting membranes from damage while the study also employs cryo-CLEM to visualize VIPP1's interaction with chloroplast membranes.
Biochemical processes in chloroplasts are important for virtually all life forms. Tight regulation of protein homeostasis and the coordinated assembly of protein complexes, composed of both imported and locally synthesized subunits, are vital to plastid functionality. Protein biogenesis requires the action of cotranslationally acting molecular chaperones.
View Article and Find Full Text PDFA considerably small fraction of approximately 60-100 proteins of all chloroplast proteins are encoded by the plastid genome. Many of these proteins are major subunits of complexes with central functions within plastids. In comparison with other subcellular compartments and bacteria, many steps of chloroplast protein biogenesis are not well understood.
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