The universally conserved HCF101 protein is involved in assembly of [4Fe-4S]-cluster-containing complexes in Arabidopsis thaliana chloroplasts

摘要: Summary The seedling-lethal nuclear Arabidopsis hcf101 (high chlorophyll fluorescence) mutant is impaired in photosynthesis and complemented by the wild-type HCF101 cDNA. Photosystem I (PSI) activity abolished, PSI core complexes fail to accumulate hcf101, whereas levels of other thylakoid membrane proteins are unaffected. Northern in vivo labelling analyses as well studies on polysome loading show that transcript translation rates proteins, which belong PSI, normal hcf101. PSI-specific fluorescence at 77 K shifted from 735 728 nm indicating exitons cannot efficiently be transferred reaction centre, whereby antenna almost Mutant plants not only mature contains three [4Fe-4S]clusters (FSCs), but also characterized reduced soluble FSC-containing complex ferredoxin-thioredoxin reductase (FTR) stroma. Inhibited FTR maturation a secondary effect stemming lack because hcf145, lacks accumulates levels. Levels [2Fe-2S] cluster-containing ferredoxin PetC, respectively, were unchanged plants. These data suggest specific role FSC biogenesis. plastid localized belongs an ancient universally conserved family P-loop ATPases previously designated ‘MRP’ (metGrelated protein) family. The function identified for suggests new designation, FSC, this