FIG. 1.

Transcription map of B19. The transcription map of B19 is shown, indicating the RNA initiation site, splice junctions (donors D1 and D2 and acceptors A1-1-A1-2 and A2-1-A2-2), and cleavage and polyadenylation sites [(pA)p1, (pA)p2, and (pA)d)], as well as the predicted protein products, for all B19 RNAs so far identified. The protein products for RNAs designated by (?) have not been characterized. The asterisks label RNAs using the second internal polyadenylation site (pA)p2, first described in this paper (see text). The positions of probes 4 (nt 2641 to 2960) and 6 (nt 2718 to 3383), used for RNase protection assays, are shown in relation to the map, and the predicted protected bands are displayed. The position of probe A (nt 2843 to 3200), used for the Northern blot analysis shown in Fig. 4, is also shown. RT, readthrough.