TY  - JOUR
A1  - Nordhues, Andre
A1  - Schöttler, Mark Aurel
A1  - Unger, Ann-Katrin
A1  - Geimer, Stefan
A1  - Schönfelder, Stephanie
A1  - Schmollinger, Stefan
A1  - Ruetgers, Mark
A1  - Finazzi, Giovanni
A1  - Soppa, Barbara
A1  - Sommer, Frederik
A1  - Mühlhaus, Timo
A1  - Roach, Thomas
A1  - Krieger-Liszkay, Anja
A1  - Lokstein, Heiko
A1  - Luis Crespo, Jose
A1  - Schroda, Michael
T1  - Evidence for a role of VIPP1 in the structural organization of the photosynthetic apparatus in chlamydomonas
JF  - The plant cell
N2  - The vesicle-inducing protein in plastids (VIPP1) was suggested to play a role in thylakoid membrane formation via membrane vesicles. As this functional assignment is under debate, we investigated the function of VIPP1 in Chlamydomonas reinhardtii. Using immunofluorescence, we localized VIPP1 to distinct spots within the chloroplast. In VIPP1-RNA interference/artificial microRNA cells, we consistently observed aberrant, prolamellar body-like structures at the origin of multiple thylakoid membrane layers, which appear to coincide with the immunofluorescent VIPP1 spots and suggest a defect in thylakoid membrane biogenesis. Accordingly, using quantitative shotgun proteomics, we found that unstressed vipp1 mutant cells accumulate 14 to 20% less photosystems, cytochrome b(6)f complex, and ATP synthase but 30% more light-harvesting complex II than control cells, while complex assembly, thylakoid membrane ultrastructure, and bulk lipid composition appeared unaltered. Photosystems in vipp1 mutants are sensitive to high light, which coincides with a lowered midpoint potential of the Q(A)/Q(A)(-) redox couple and increased thermosensitivity of photosystem II (PSII), suggesting structural defects in PSII. Moreover, swollen thylakoids, despite reduced membrane energization, in vipp1 mutants grown on ammonium suggest defects in the supermolecular organization of thylakoid membrane complexes. Overall, our data suggest a role of VIPP1 in the biogenesis/assembly of thylakoid membrane core complexes, most likely by supplying structural lipids.
Y1  - 2012
U6  - https://doi.org/10.1105/tpc.111.092692
SN  - 1040-4651
VL  - 24
IS  - 2
SP  - 637
EP  - 659
PB  - American Society of Plant Physiologists
CY  - Rockville
ER  - 
TY  - JOUR
A1  - Lokstein, Heiko
A1  - Betke, Alexander
A1  - Krikunova, Maria
A1  - Teuchner, Klaus
A1  - Voigt, Bernd
T1  - Elucidation of structure-function relationships in plant major light-harvesting complex (LHC II) by nonlinear spectroscopy
JF  - Photosynthesis research
N2  - Conventional linear and time-resolved spectroscopic techniques are often not appropriate to elucidate specific pigment-pigment interactions in light-harvesting pigment-protein complexes (LHCs). Nonlinear (laser-) spectroscopic techniques, including nonlinear polarization spectroscopy in the frequency domain (NLPF) as well as step-wise (resonant) and simultaneous (non-resonant) two-photon excitation spectroscopies may be advantageous in this regard. Nonlinear spectroscopies have been used to elucidate substructure(s) of very complex spectra, including analyses of strong excitonic couplings between chlorophylls and of interactions between (bacterio) chlorophylls and "optically dark'' states of carotenoids in LHCs, including the major antenna complex of higher plants, LHC II. This article shortly reviews our previous study and outlines perspectives regarding the application of selected nonlinear laser-spectroscopic techniques to disentangle structure-function relationships in LHCs and other pigment-protein complexes.
KW  - Excitonic interactions
KW  - Laser spectroscopy
KW  - Light-harvesting complex (LHC II)
Y1  - 2012
U6  - https://doi.org/10.1007/s11120-011-9700-y
SN  - 0166-8595
VL  - 111
IS  - 1-2
SP  - 227
EP  - 235
PB  - Springer
CY  - Dordrecht
ER  -