Structure of plant photosystem I in a native assembly state defines PsaF as a regulatory checkpoint
Andreas Naschberger, Maria Fadeeva, Daniel Klaiman, Anna Borovikova-Sheinker, Ido Caspy, Nathan Nelson, Alexey Amunts
Abstract
Plant photosystem I (PSI) consists of at least 13 nuclear-encoded and 4 chloroplast-encoded subunits that together act as a sunlight-driven oxidoreductase. Here we report the structure of a PSI assembly intermediate that we isolated from greening oat seedlings. The assembly intermediate shows an absence of at least eight subunits, including PsaF and LHCI, and lacks photoreduction activity. The data show that PsaF is a regulatory checkpoint that promotes the assembly of LHCI, effectively coupling biogenesis to function.
Topics & Concepts
Photosystem IBiogenesisChloroplastPhotosystem IIPhotosynthesisFunction (biology)BiologyChemistryBiophysicsCell biologyBotanyBiochemistryGenePhotosynthetic Processes and MechanismsMitochondrial Function and PathologyEnzyme Structure and Function