A. Seluanov et E. Bibi, FTSY, THE PROKARYOTIC SIGNAL RECOGNITION PARTICLE RECEPTOR HOMOLOG, IS ESSENTIAL FOR BIOGENESIS OF MEMBRANE-PROTEINS, The Journal of biological chemistry, 272(4), 1997, pp. 2053-2055
In mammalian cells, many secretory proteins are targeted to the endopl
asmic reticulum co-translationally, by the signal recognition particle
(SRP) and its receptor. In Escherichia coli, the targeting of secreto
ry proteins to the inner membrane can be accomplished post-translation
ally. Unexpectedly, despite this variance, E. coli contains essential
genes encoding Ffh and FtsY with a significant similarity to proteins
of the eukaryotic SRP machinery. In this study, we investigated the po
ssibility that the prokaryotic SRP-like machinery is involved in bioge
nesis of membrane proteins in E. coli. The data presented here demonst
rate that the SRP-receptor homologue, FtsY, is indeed essential for ex
pression of integral membrane proteins in E. coli, indicating that, in
the case of this group of proteins, FtsY and the mammalian SRP recept
or have similar functions.