Signal recognition particle RNA (SRP RNA)

The signal recognition particle RNA (SRP RNA, 7SL RNA) is a non-coding RNA that forms the RNA core of the signal recognition particle, a ribonucleoprotein complex universally required for cotranslational protein targeting in eukaryotes and archaea. It interacts with a set of SRP proteins (in metazoa: SRP9, SRP14, SRP19, SRP54, SRP68, SRP72). SRP RNA binds the SRP54 protein, participates in critical RNA-protein interactions that facilitate recognition of signal peptides on nascent polypeptides, and catalyzes GTP hydrolysis necessary for protein targeting. It enables the SRP to halt translation temporarily and direct ribosome–nascent chain complexes to the ER membrane, where they bind the SRP receptor and resume translation across the membrane. The sequence and secondary structure of the SRP RNA are highly conserved among metazoans, though they vary somewhat in other kingdoms. The metazoan 7SL RNA (~300 nucleotides) is distinguished from bacterial 4.5S SRP RNA in length and structure. It is not considered a druggable target.

Other names

7SL RNA6S RNAffs4.5S RNA