Bacteriophage phi29 utilizes a DNA packaging motor that contains a 174nt RNA multimer. The motor is situated at the vertex of the prohead and utilizes the RNA multimer to bridge the packing machinery to the head-tail connector.
Kitamura A, Jardine PJ, Anderson DL, Grimes S, Matsuo H. "Analysis of intermolecular base pair formation of prohead RNA of the phage phi29 DNA packaging motor using NMR spectroscopy." Nucleic acids research 36.3 (2008):839-848.
Harjes E, Kitamura A, ZhaoW, Morais M, JardineP.J, GrimesSand MatsuoH. “Revealing RNA claw of bacteriophage f29” Nucleic Acids Research, DOI: GKS724, In press