Comparison of the Gene Coding Contents and Other Unusual Features of the GC-Rich and AT-Rich Branch Probosciviruses

摘要: ABSTRACT Nearly 100 cases of lethal acute hemorrhagic disease in young Asian elephants have been reported worldwide. All tested contained high levels elephant endotheliotropic herpesvirus (EEHV) DNA pathological blood or tissue samples. Seven known major types EEHVs partially characterized and shown to all belong the novel Proboscivirus genus. However, recently determined 206-kb EEHV4 genome proved represent prototype a GC-rich branch virus that is very distinct from previously published 180-kb EEHV1A, EEHV1B, EEHV5A genomes, which fall within an alternative AT-rich branch. Although retains large family 7xTM vGPCR-like genes, six are unique either just one other While both branches display highly enriched distribution A T tracts intergenic domains, they generally much larger Both retain vGCNT1 acetylglucosamine transferase at least vOX-2 gene, but two differ by 25 genes overall, with encoding fucosyl (vFUT9) plus three more vOX2 proteins immunoglobulin-like gene absent Several envelope glycoproteins only 15 20% protein identity less across branches. Finally, plausible predicted transcriptional regulatory no homology those alpha-, beta-, gammaherpesvirus subfamilies. These results reinforce our previous proposal probosciviruses should be designated new subfamily mammalian herpesviruses. IMPORTANCE Multiple species herpesviruses different lineages genus (EEHV1/6, EEHV2/5, EEHV3/4/7) infect African elephants, largely confined calves predominantly associated EEHV1. In accompanying paper [P. D. Ling et al., mSphere 1(3):e00081-15, 10.1128/mSphere.00081-15], we report complete EEHV4, third causing first example proboscivirus. To gain insights into nature differential properties these anciently diverged herpesviruses, describe here several additional unusual features found particular emphasis on patterns divergence as well common such enlarged domains families, including number proteins.