Project Details
Projekt
Function of thylakoid low molecular weight proteins and assembly factors in the biogenesis, activity and stability of photosynthetic complexes
Applicant
Privatdozent Dr. Jörg Meurer
Subject Area
Plant Biochemistry and Biophysics
Plant Physiology
Plant Physiology
Term
from 2014 to 2018
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 263978931
An intriguing feature of the photosynthetic complexes of the thylakoid membrane is their high number of low molecular weight (LMW) proteins, which are nuclear and plastid encoded. Here we investigate the distinct function of assembly factors and of individual LMW proteins in the biogenesis, light absorbance, electron transport processes, phosphorylation, stabilisation and repair mainly of photosystem (PS)II using available knockouts of corresponding nuclear and plastid genes in Arabidopsis and tobacco, respectively. Furthermore, the mutant repertoire will be used to identify the composition of subcomplexes appearing during assembly and their localisation within the thylakoid system using native gels, co-immunoprecipitation (Co-IP), chromatography, cross-linking, tagged proteins, fractionation techniques and mass spectrometry. We provide clear evidence that the LMW membrane protein PsbN, which hitherto was annotated as PSII subunit, is not part of this complex but essentially required for assembly of its heterodimeric reaction centre. Direct interaction partners of PsbN and proteins associated in several precomplexes together with PsbN will be identified, already obtained interacting factors will be verified and analysed using split-ubiquitin assays, protein overlay assays, SPR spectrometry, Co-IP with tagged versions of PsbN and mass spectrometry. The addressed issues assist in our understanding of the stepwise assembly, light capture, transfer of electrons within and outgoing of PSII, water splitting and O2 evolution, membrane dynamics and recovery of the susceptible PSII from photoinhibition and heat inactivation.
DFG Programme
Research Grants
International Connection
Denmark, Norway, Sweden
