The 5′ region of Tacaribe virus L RNA encodes a protein with a potential metal binding domain

We have just completed the Tacaribe arenavirus (TV) genome structure by sequencing the 5′ region of the L RNA. Analysis of the sequence has indicated the existence of an open reading frame (ORF) in the viral sense RNA encoding a 95 amino acid polypeptide. The first in phase AUG codon is in positions 70–72 from the 5′ end of the viral RNA surrounded by a sequence favorable for the initiation of protein synthesis. The ORF ends at positions 355–357. The predicted polypeptide (P 11 contains a cysteine-rich sequence bearing a remarkable similarity to the “zinc finger” sequences found in a number of proteins. We have recently reported that the 3′ region of the TV L RNA encodes a polypeptide comprising 2210 amino acids in the viral-complementary sequence. This latter gene, i.e., the L gene, terminates at positions 442-440 from the 5′ end of the viral RNA. The two genes encoded by the L RNA (L and P 11) are in opposite strands of the RNA in sequences that do not overlap, but are separated by a noncoding intergenic region of 82 nucleotides. The nucleotide sequence of the intergenic region leads to the prediction of a strong secondary structure.