Signal recognition particle (SRP) is a ribonucleoprotein which targets specific proteins to the endoplasmic reticulum (ER) in eukaryotes and the plasma membrane in prokaryotes. In eukaryotes SRP binds to the signal sequence of a newly synthesized polypeptide as it emerges from the ribosome. The binding allows for the coupling of the translation process to the translocation process. The SRP targets the nascent protein to the ER by docking into the SRP receptor[1]. The eukaryotic SRP which has GTPase activity, is composed of SRP9, SRP14[2], SRP19[3], SRP54[4], SRP68, SRP72[5] and 7S RNA. The prokaryotic SRP is composed of FFH (SRP54-like) and 4.5S RNA.
3D structures of signal recognition particle
Signal recognition particle 3D structures
References
- ↑ Halic M, Beckmann R. The signal recognition particle and its interactions during protein targeting. Curr Opin Struct Biol. 2005 Feb;15(1):116-25. PMID:15718142 doi:http://dx.doi.org/10.1016/j.sbi.2005.01.013
- ↑ Bovia F, Fornallaz M, Leffers H, Strub K. The SRP9/14 subunit of the signal recognition particle (SRP) is present in more than 20-fold excess over SRP in primate cells and exists primarily free but also in complex with small cytoplasmic Alu RNAs. Mol Biol Cell. 1995 Apr;6(4):471-84. PMID:7542942
- ↑ Dean KA, von Ahsen O, Gorlich D, Fried HM. Signal recognition particle protein 19 is imported into the nucleus by importin 8 (RanBP8) and transportin. J Cell Sci. 2001 Oct;114(Pt 19):3479-85. PMID:11682607
- ↑ Gowda K, Black SD, Moeller I, Sakakibara Y, Liu MC, Zwieb C. Protein SRP54 of human signal recognition particle: cloning, expression, and comparative analysis of functional sites. Gene. 1998 Jan 30;207(2):197-207. PMID:9511762
- ↑ Lutcke H, Prehn S, Ashford AJ, Remus M, Frank R, Dobberstein B. Assembly of the 68- and 72-kD proteins of signal recognition particle with 7S RNA. J Cell Biol. 1993 Jun;121(5):977-85. PMID:8388879
