Involvement of a chloroplast homologue of the signal recognition particle receptor protein, FtsY, in protein targeting to thylakoids.
We isolated an Arabidopsis thaliana cDNA whose translated product shows sequence similarity to the FtsY, a bacterial homologue of SRP receptor protein. The Arabidopsis FtsY homologue contains a typical chloroplast transit peptide. The in vitro-synthesized 37 kDa FtsY homologue was imported into chloroplasts, and the processed 32 kDa polypeptide bound peripherally on the outer surface of thylakoids. Antibodies raised against the FtsY homologue also reacted with a thylakoid-bound 32 kDa protein. The antibodies inhibited the cpSRP-dependent insertion of the light-harvesting chlorophyll alb-binding protein into thylakoid membranes suggesting that the chloroplast FtsY homologue is involved in the cpSRP-dependent protein targeting to the thylakoid membranes.
Kogata
N
N
Institute for Protein Research, Osaka University, Suita, Japan.
Nishio
K
K
Hirohashi
T
T
Kikuchi
S
S
Nakai
M
M
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics / Q000378:metabolism; D001412:Bacillus subtilis / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D001693:Biological Transport, Active; D002736:Chloroplasts / Q000378:metabolism*; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D018744:DNA, Plant / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D018271:Signal Recognition Particle / Q000235:genetics
D001426:Bacterial Proteins; D018076:DNA, Complementary; D018744:DNA, Plant; C087406:FtsY protein, Bacteria; D010940:Plant Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D018271:Signal Recognition Particle