Restriction enzyme cleavage maps of the DNA of two cauliflower mosaic virus isolates

Abstract

To provide a physical basis for the functional mapping of the cauliflower mosaic virus (CaMV) genome, restriction enzyme cleavage maps of the DNA of CaMV isolates NY8153 and CM4-184-OS (a variant of CM4-184) were constructed. CM4-184-OS DNA contained five EcoRI, eight HindIII six BglIII, and two BamHI cleavage sites, while NY8153 DNA contained one additional HindIII site and one fewer EcoRI site. Fragments were ordered by examination of multienzyme and partial digests. The resulting maps revealed that the CM4-184-OS genome was 5.5% smaller than that of NY8153, because CM4-184-OS was deleted for 463 ± 10 base pairs including the HindIII site at 0.427 map unit (relative to a common EcoR1 site) and the S 1 site at 0.45 map unit on NY8153 DNA. Since the deleted region did not include the two BamHI sites, this variant of the CM4-184 isolate is different from the John Innes variant of CM4-184 (R. Hull, and S. H. Howell, Virology 86, 482–493, 1978) which is deleted for a different, but overlapping region of the CaMV genome.