7SL RNA

7SL RNA is an RNA molecule, component of the signal recognition particle (SRP).

Although originally the SRP was thought to be only composed by 6 polypeptides, this small cytoplasmic RNA molecule was found to be a component of the complex.

The RNA gene for 7SL is transcribed by the RNA polymerase III.

The common SINE family Alu probably originated from a duplication of a 7SL RNA gene.