The inner membrane associated protein of 30 kDa (IM30)
The inner membrane associated protein of 30 kDa (IM30) is crucial in thylakoid membrane biogenesis in chloroplasts and cyanobacteria. IM30 oligomerizes into beautiful ring structures. Recently, we could demonstrate via in vitro experiments, such as fluorescence spectroscopy and electron microscopy, that the protein is able to mediate membrane fusion in the presence of Mg2+. In fact, IM30 was the first protein connected to membrane fusion in chloroplasts and prokaryotes. This discovery opened up a wide field of questions concerning structural properties of IM30 and its mode of action, which we are currently addressing (and answering :-)) within our group.
- Heidrich, J., Thurotte, A. and Schneider D. (2017) Specific interaction of IM30/Vipp1 with cyanobacterial and chloroplast membranes results in membrane remodeling and eventually in membrane fusion, Biochim. Biophys. Acta - Biomembranes 1859, 537–549
- Hennig, R., Heidrich, J., Saur, M., Schmüser, L., Roeters, S.J., Hellmann, N., Woutersen, S., Bonn, M., Weidner, T., Markl, J. and Schneider, D. (2015) IM30 triggers membrane fusion in cyanobacteria and chloroplasts, Nature Comm. 6, 7018
Dynamin like proteins (DLPs)
DLPs are mechano-chemical GTPases, which are involved in remodeling processes at various eukaryotic cell membranes. The classical dynamin protein is e.g. involved in vesicle formation at the plasma membrane. However, DLPs are also found organelles of prokaryotic origin (mitochondria and chloroplasts) as well as in bacteria. Due to their described membrane remodeling activity, DLPs are likely involved in thylakoid membrane biogenesis and dynamics in chloroplasts and cyanobacateria. Currently, we investigate the structure and activity of a DLP of the cyanobacterium Synechocystis sp. PCC6803. Besides in vivo analyses of mutant strains, we mainly evaluate the activity of the isolated protein in vitro and its impact on membrane structure and dynamics.