Comparison of genome structures among three different strains of avian erythroblastosis virus

The genomic DNAs of two strains of avian erythroblastosis virus (AEV), AEV-R and AEV-H, were molecularly cloned in Escherichia coli using lambda Charon 16A as a vector. Comparison of the restriction maps of the cloned DNAs with that of AEV-ES4 DNA revealed that R strain is identical with ES4 strain, but totally differs from H strain. The erbB gene product of AEV-R and that of AEV-H were shown to be glycoproteins with molecular weights of 68,000 and 72,000, respectively. Nucleotide sequence analysis of the 3' part of the erbB gene showed that the erbB gene in AEV-R is 126 base pairs (bp) shorter than that in AEV-H, which might result in some difference in tumorigenicity between these viruses.