Completion of the Lassa Fever Virus Sequence and Identification of a RING Finger Open Reading Frame at the L RNA 5′ End

AbstractLassa (LAS) fever virus is a highly pathogenic arenavirus with large (L) and small (S) RNA genomic segments. The 5′ end of the LAS L segment is described here, thereby completing the sequence of the most virulent arenavirus analyzed to date. In keeping with the ambisense gene structure of the arenaviruses, the LAS L RNA encodes a 250-kDa protein and an 11-kDa protein in opposite senses with respect to each other. The 11-kDa protein, defined previously in arenaviruses lymphocytic choriomeningitis (LCM), Tacaribe (TAC), and Pichinde (PIC), contains a RING type of zinc-binding structure. Expression of the 11-kDa protein in LAS virus-infected cells has been confirmed by binding to peptide-specific antibody