Multiple, discrete 35S transcripts of cauliflower mosaic virus.

We have devised a modification of the Berk and Sharp procedure that allows us to detect the presence of a diverse population of 35S full-length, genomic viral transcripts of cauliflower mosaic virus (CaMV). Using this procedure we have been able to identify and characterize four such 35S transcripts. The first 35S RNA that we have mapped, 35S-1, is a slightly longer than full-length transcript, beginning approximately at nucleotide 7500 and ending at nucleotide 7650 and corresponds to a previously characterized 35S transcript of the CabbB-JI strain of CaMV. The second transcript, 35S-2, begins and ends near nucleotide 8000 on the genome map. The third and fourth 35S RNAs, 35S-3, and 35S-4, have their 5' ends lying, respectively, at approximately nucleotides 1200 and 2100, while their 3' ends lie near nucleotides 1300 and 1900. In addition to the four characterized 35S RNAs, we present evidence for a fifth 35S RNA which may begin and end near nucleotide 5700.