Herpesvirus ateles DNA and Its Homology with Herpesvirus saimiri Nucleic Acid

Abstract

Analysis of the structural organization of Herpesvirus ateles DNA shows that 2 types of viral DNA molecules are encapsidated in virions: M-genomes, which contain 74% light sequences (L-DNA, 38% guanine plus cytosine) [G + C] and 26% highly repetitive heavy sequences (H-DNA, 75% G + C), and defective H-genomes, which consist exclusively of repetitive H-DNA. The structure of M-genomes from Herpesvirus ateles consists of an L-DNA region of about 70 .times. 106 daltons inserted between H-DNA termini of variable length. M-genomes with a shorter H-DNA region at 1 end of the molecule have a long stretch of H-DNA at the other end, resulting in a total MW of 89.8 .+-. 8.5 .times. 106. Thus it resembles the structure of M-genomes of Herpesvirus saimiri. H-DNA of the two independent Herpesvirus ateles isolates, strains 810 and 73, reveals different patterns after cleavage with restriction endonuclease Sma I. H-DNA of Herpesvirus ateles 810 appears to consist of identical tandem repeat units with a MW of 1,035,000; the H-DNA repeat unit of strain 73 is shorter (930,000 MW). Corresponding DNA sequences of the 2 Herpesvirus ateles strains (810 and 73) are completely homologous in cross-hybridizations. A discrete nucleotide sequence divergence between these virus strains is detected by measuring melting temperatures (Tm) of DNA hybrid molecules. Some homology exists between Herpesvirus ateles and Herpesvirus saimiri DNA. Hybridization of L-DNA from Herpesvirus ateles with L-DNA from Herpesvirus saimiri shows about a 35% homology between the respective L-DNA sequences; the resulting heteroduplex molecules show a decrease of Tm by 13.5.degree. C, corresponding to about a 9% mismatching in cross-hybridizing parts of L-regions. Very little homology is found between H-DNA of Herpesvirus ateles and Herpesvirus saimiri.