F4I18.25 Signal recognition particle receptor protein. Binds GTP specifically. The GTPase activity is inhibited by the N-terminus of the protein until binding to the thylakoid membrane. Activates the GTPase activity of FFC/cpSRP54 when bound to the cpSRP complex. Required for light-harvesting chlorophyll a/b-binding protein (LHCP) integration into thylakoids. Might be also functionally linked to the Sec translocation machinery. FTSY Cell division protein FtsY homolog, chloroplastic MATSSAHLSFLAGRISPFSSERIGLFPLRGEFRPRMTRFRCSAGPSGFFTRLGRLIKEKAKSDVEKVFSGFSKTRENLAVIDELLLFWNLAETDRVLDELEEALLVSDFGPKITVRIVERLREDIMSGKLKSGSEIKDALKESVLEMLAKKNSKTELQLGFRKPAVIMIVGVNGGGKTTSLGKLAHRLKNEGTKVLMAAGDTFRAAASDQLEIWAERTGCEIVVAEGDKAKAATVLSKAVKRGKEEGYDVVLCDTSGRLHTNYSLMEELIACKKAVGKIVSGAPNEILLVLDGNTGLNMLPQAREFNEVVGITGLILTKLDGSARGGCVVSVVEELGIPVKFIGVGEAVEDLQPFDPEAFVNAIFS Fused signal recognition particle receptor CPFTSY Chloroplast SRP receptor homolog, alpha subunit CpFtsY 366 At2g45770 CFTSY_ARATH