FIG. 1.

Construction of the full-length ANV cDNA clone and infectivity. Open boxes, partial and full-length viral cDNA; solid box, RNA transcribed in vitro from pANV-750; arrowheads, T7 promoter; CMV, human cytomegalovirus immediate-early gene promoter; star, point mutation introduced by PCR; small arrow, primer direction and position (see Table 1); −, negative for infectious virus; +, positive for infectious virus (see Fig. 7). In vitro transcripts prepared from the full-length ANV cDNA clone or a plasmid which can transcribe the genonic-size ANV RNA under the control of the CMV promoter were transfected onto CK or BHK cells using Lipofectin reagent (Bethesda Research Laboratories). The cells were tested for the presence of ANV antigens by FA tests 2 days after transfection.