FIG. 4.

Diagrammatic representation of the nucleotide sequences of the MoFe2-MuLV LTR and of the predominant PCR products from MoFe2-MuLV-induced tumors. LTRs amplified from relatively early arising lymphomas (A) and relatively late arising lymphomas (B). The enhancer (stippled boxes), predicted nuclear protein binding sites within the enhancer (21), the 21-bp sequence triplication (open boxes), and the spacing between the elements are indicated. 477 and 493 represent different litters of mice inoculated independently. Multiple amplification products derived from one tumor are indicated by the letters a and b (e.g., 477-3a and 477-3b).