@PhdThesis{diss_mods_00023757,
  author = 	{Springstein, Benjamin Lennart},
  title = 	{Identification and functional characterization of cytoskeletal proteins in cyanobacteria},
  year = 	{2018},
  publisher = 	{Christian-Albrechts-Universit{\"a}t zu Kiel},
  address = 	{Kiel},
  keywords = 	{cyanobacteria; cytoskeleton; intermediate; filament; CCRPs; Cyanobakterien; Cytoskelett; Intermedi{\"a}rfilament},
  abstract = 	{Cytoskeletal proteins have been long thought to be eukaryote-specific, however, studies of the past 30 years have demonstrated that they exist also in prokaryotes where they regulate essential cellular processes. Intermediate filament (IF)-like coiled-coil rich proteins (CCRPs) were identified in several bacterial species and were shown to regulate cell shape in Caulobacter crescentus and mechanical resistance in Streptomyces coelicolor. The Cyanobacteria phylum is renowned for its enormous morphological diversity. The prokaryotic microtubule homolog FtsZ and the actin-like protein MreB have been studied in cyanobacteria as determinants of cell-shape. Nonetheless, information on IF proteins in the phylum is still lacking. Here we show that IF-like coiled-coil rich cytoskeletal proteins are widespread in cyanobacteria and that they regulate cell shape, motility and trichome integrity. Employing the COILS algorithm, we found several thousand CCRPs in cyanobacteria and experimentally characterized 21 IF-like protein candidates, which revealed ten novel IF-like cytoskeletal proteins. CCRPs had the tendency to assemble into sheet-like structures in vitro. Though, several of the proteins studied show a high level of sequence conservation, our results suggest that their function may vary between species. CCRPs were shown to form interconnected networks with other CCRPs, jointly performing their cellular tasks. Furthermore, a sophisticated cytoskeletal network was identified in Anabaena sp. PCC 7120, including at least four CCRPs -- Alr0931, Alr4504, Alr4505 and All2460. Together with the MreB cytoskeleton, they provide scaffolding and stabilizing properties, which link neighboring cells through intercellular pore complexes (i.e., the septosomes). Notably, the polymerization of Alr4504 and Alr4505 is interdependent as they are assembled into heteropolymers only upon co-expression. Thus, this study reveals multiple novel IF-like cytoskeletal proteins in cyanobacteria.},
  url = 	{https://macau.uni-kiel.de/receive/diss_mods_00023757},
  file = 	{:https://macau.uni-kiel.de/servlets/MCRFileNodeServlet/diss_derivate_00000044/doktorarbeit_benjamin_springstein.pdf:PDF},
  language = 	{en}
}