Protein translocation across the thylakoid membrane--a tale of two mechanisms.
In vitro reconstitution assays have been used in recent years to probe the mechanisms by which a variety of cytosolically synthesised proteins are transported across the thylakoid membrane within higher plant chloroplasts. The emerging data suggest that two distinct mechanisms operate. Translocation of a subset of lumenal proteins, namely the 23 kDa and 16 kDa proteins of the oxygen-evolving complex, and of the CFo2 protein (an integral membrane protein), requires only the presence of the thylakoidal delta pH. In contrast, two other lumenal proteins, the 33 kDa oxygen-evolving complex protein and plastocyanin, require also the presence of ATP and at least one stromal factor for efficient transport into isolated thylakoids to take place.
Department of Biological Sciences, University of Warwick, Coventry, UK.
C
C
Robinson
R B
RB
Klösgen
R G
RG
Herrmann
J B
JB
Shackleton
D001692:Biological Transport; D002736:Chloroplasts / Q000648:ultrastructure*; D007425:Intracellular Membranes / Q000378:metabolism*; D008565:Membrane Proteins / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism*
D008565:Membrane Proteins; D010940:Plant Proteins