TY  - JOUR
A1  - Barchewitz, Tino
A1  - Guljamow, Arthur
A1  - Meißner, Sven
A1  - Timm, Stefan
A1  - Henneberg, Manja
A1  - Baumann, Otto
A1  - Hagemann, Martin
A1  - Dittmann, Elke
T1  - Non-canonical localization of RubisCO under high-light conditions in the toxic cyanobacterium Microcystis aeruginosa PCC7806
JF  - Environmental microbiology
N2  - The frequent production of the hepatotoxin microcystin (MC) and its impact on the lifestyle of bloom-forming cyanobacteria are poorly understood. Here, we report that MC interferes with the assembly and the subcellular localization of RubisCO, in Microcystis aeruginosa PCC7806. Immunofluorescence, electron microscopic and cellular fractionation studies revealed a pronounced heterogeneity in the subcellular localization of RubisCO. At high cell density, RubisCO particles are largely separate from carboxysomes in M. aeruginosa and relocate to the cytoplasmic membrane under high-light conditions. We hypothesize that the binding of MC to RubisCO promotes its membrane association and enables an extreme versatility of the enzyme. Steady-state levels of the RubisCO CO2 fixation product 3-phosphoglycerate are significantly higher in the MC-producing wild type. We also detected noticeable amounts of the RubisCO oxygenase reaction product secreted into the medium that may support the mutual interaction of M. aeruginosa with its heterotrophic microbial community.
Y1  - 2019
U6  - https://doi.org/10.1111/1462-2920.14837
SN  - 1462-2912
SN  - 1462-2920
VL  - 21
IS  - 12
SP  - 4836
EP  - 4851
PB  - Wiley
CY  - Hoboken
ER  - 
TY  - GEN
A1  - Grafe, Marianne
A1  - Batsios, Petros
A1  - Meyer, Irene
A1  - Lisin, Daria
A1  - Baumann, Otto
A1  - Goldberg, Martin W.
A1  - Gräf, Ralph
T1  - Supramolecular Structures of the Dictyostelium Lamin NE81
T2  - Potsprint der Universität Potsdam Mathematisch-Naturwissenschaftliche Reihe
N2  - Nuclear lamins are nucleus-specific intermediate filaments (IF) found at the inner nuclear membrane (INM) of the nuclear envelope (NE). Together with nuclear envelope transmembrane proteins, they form the nuclear lamina and are crucial for gene regulation and mechanical robustness of the nucleus and the whole cell. Recently, we characterized Dictyostelium NE81 as an evolutionarily conserved lamin-like protein, both on the sequence and functional level. Here, we show on the structural level that the Dictyostelium NE81 is also capable of assembling into filaments, just as metazoan lamin filament assemblies. Using field-emission scanning electron microscopy, we show that NE81 expressed in Xenopous oocytes forms filamentous structures with an overall appearance highly reminiscent of Xenopus lamin B2. The in vitro assembly properties of recombinant His-tagged NE81 purified from Dictyostelium extracts are very similar to those of metazoan lamins.
Super-resolution stimulated emission depletion (STED) and expansion microscopy (ExM), as well as transmission electron microscopy of negatively stained purified NE81, demonstrated its capability of forming filamentous structures under low-ionic-strength conditions. These results recommend Dictyostelium as a non-mammalian model organism with a well-characterized nuclear envelope involving all relevant protein components known in animal cells.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 682 
KW  - lamin
KW  - NE81
KW  - Dictyostelium
KW  - nuclear envelope
KW  - nuclear lamina
KW  - expansion microscopy
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-425976
SN  - 1866-8372
IS  - 682
ER  - 
TY  - JOUR
A1  - Grafe, Marianne
A1  - Batsios, Petros
A1  - Meyer, Irene
A1  - Lisin, Daria
A1  - Baumann, Otto
A1  - Goldberg, Martin W.
A1  - Gräf, Ralph
T1  - Supramolecular Structures of the Dictyostelium Lamin NE81
JF  - Cells
N2  - Nuclear lamins are nucleus-specific intermediate filaments (IF) found at the inner nuclear membrane (INM) of the nuclear envelope (NE). Together with nuclear envelope transmembrane proteins, they form the nuclear lamina and are crucial for gene regulation and mechanical robustness of the nucleus and the whole cell. Recently, we characterized Dictyostelium NE81 as an evolutionarily conserved lamin-like protein, both on the sequence and functional level. Here, we show on the structural level that the Dictyostelium NE81 is also capable of assembling into filaments, just as metazoan lamin filament assemblies. Using field-emission scanning electron microscopy, we show that NE81 expressed in Xenopous oocytes forms filamentous structures with an overall appearance highly reminiscent of Xenopus lamin B2. The in vitro assembly properties of recombinant His-tagged NE81 purified from Dictyostelium extracts are very similar to those of metazoan lamins.
Super-resolution stimulated emission depletion (STED) and expansion microscopy (ExM), as well as transmission electron microscopy of negatively stained purified NE81, demonstrated its capability of forming filamentous structures under low-ionic-strength conditions. These results recommend Dictyostelium as a non-mammalian model organism with a well-characterized nuclear envelope involving all relevant protein components known in animal cells.
KW  - lamin
KW  - NE81
KW  - Dictyostelium
KW  - nuclear envelope
KW  - nuclear lamina
KW  - expansion microscopy
Y1  - 2019
U6  - https://doi.org/10.3390/cells8020162
SN  - 2073-4409
VL  - 8
IS  - 2
PB  - Molecular Diversity Preservation International
CY  - Basel
ER  -