This protein binds specifically to 23S rRNA. It makes multiple contacts with different domains of the 23S rRNA in the assembled 50S subunit and ribosome. Contacts all 6 domains of the 23S rRNA, helping stabilize their relative orientation. An extended beta-hairpin in the C-terminus forms part of the polypeptide exit tunnel, in which it helps forms a bend with protein L4, while most of the rest of the protein is located at the polypeptide exit tunnel on the outside of the subunit. Part of the 50S ribosomal subunit. Contacts the macrolide antibiotic tylosin in the polypeptide exit tunnel. Belongs to the universal ribosomal protein uL22 family.