Phospho-mimicry mutant of atToc33 affects early development of Arabidopsis thaliana.
The precursor protein receptor at the chloroplast outer membrane atToc33 is a GTPase, which can be inactivated by phosphorylation in vitro, being arrested in the GDP loaded state. To assess the physiological function of phosphorylation, attoc33 knock out mutants were complemented with a mutated construct mimicking the constitutively phosphorylated state. Our data suggest that the reduced functionality of the mutant protein can be compensated by its upregulation. Chloroplast biogenesis and photosynthetic activity are impaired in the mutants during the early developmental stage, which is consistent with the requirement of atToc33 in young photosynthetic tissues.
LMU München, Department of Biology I, Menzinger Strasse 67, 80638 München, Germany.
Mislav
M
Oreb
Mikael
M
Zoryan
Aleksandar
A
Vojta
Uwe G
UG
Maier
Lutz A
LA
Eichacker
Enrico
E
Schleiff
D017360:Arabidopsis / Q000235:genetics / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D005816:Genetic Complementation Test; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D018716:Molecular Mimicry; D050505:Mutant Proteins / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D010766:Phosphorylation; D010788:Photosynthesis; D020524:Thylakoids / Q000648:ultrastructure; D015854:Up-Regulation / Q000235:genetics
D029681:Arabidopsis Proteins; D002352:Carrier Proteins; D008565:Membrane Proteins; D050505:Mutant Proteins; C469717:Ppi1 protein, Arabidopsis; C114786:Toc33 protein, Arabidopsis