TY - JOUR
T1 - Comparison of the gene coding contents and other unusual features of the GC-rich and AT-rich branch probosciviruses
AU - Ling, Paul D.
AU - Long, Simon Y.
AU - Zong, Jian Chao
AU - Heaggans, Sarah Y.
AU - Qin, Xiang
AU - Hayward, Gary S.
N1 - Funding Information:
J.-C.Z. and S.Y.L. carried out large amounts of initial comparative PCR DNA sequencing from all seven EEHV species that led to identification of many of the novel features and insights described here. G.S.H. and S.Y.H. carried out all of the DNA sequence difference analyses and comparisons for identifying ORFs and generated the gene annotations for GenBank as well as the phylogenetic trees. P.D.L. and X.Q. coordinated and carried the intact genome sequencing projects for both EEHV1(Kimba) and EEHV4(Baylor), and P.D.L. generated the genome maps. G.S.H. wrote the manuscript. All authors read and provided input to the manuscript. Paul D. Ling received research funding from the Houston Zoo. Simon Y. Long is the recipient of a Morris Animal Foundation Postdoctoral Fellowship (D14ZO-411). Partial funding support for the studies at Johns Hopkins University was obtained by research grants to Gary S. Hayward from the International Elephant Foundation. Both the Ling and Hayward groups were also supported by subcontracts within a Leadership Grant (MG-30-130086-13) under the Collections Stewardship Program awarded to Lauren Howard at the Houston Zoo by the Institute of Museum and Library Services. The HGSC is funded by the National Human Genome Research Institute, National Institutes of Health grant U54 HG003273 to Richard Gibbs
Publisher Copyright:
© 2016 Ling et al.
PY - 2016/5/1
Y1 - 2016/5/1
N2 - Nearly 100 cases of lethal acute hemorrhagic disease in young Asian elephants have been reported worldwide. All tested cases contained high levels of elephant endotheliotropic herpesvirus (EEHV) DNA in pathological blood or tissue samples. Seven known major types of EEHVs have been partially characterized and shown to all belong to the novel Proboscivirus genus. However, the recently determined 206-kb EEHV4 genome proved to represent the prototype of a GC-rich branch virus that is very distinct from the previously published 180-kb EEHV1A, EEHV1B, and EEHV5A genomes, which all fall within an alternative AT-rich branch. Although EEHV4 retains the large family of 7xTM and vGPCR-like genes, six are unique to either just one or the other branch. While both branches display a highly enriched distribution of A and T tracts in intergenic domains, they are generally much larger within the GC-rich branch. Both branches retain the vGCNT1 acetylglucosamine transferase and at least one vOX-2 gene, but the two branches differ by 25 genes overall, with the AT-rich branch encoding a fucosyl transferase (vFUT9) plus two or three more vOX2 proteins and an immunoglobulin-like gene family that are all absent from the GC-rich branch. Several envelope glycoproteins retain only 15 to 20% protein identity or less across the two branches. Finally, the two plausible predicted transcriptional regulatory proteins display no homology at all to those in the alpha-, beta-, or gammaherpesvirus subfamilies. These results reinforce our previous proposal that the probosciviruses should be designated a new subfamily of mammalian herpesviruses.
AB - Nearly 100 cases of lethal acute hemorrhagic disease in young Asian elephants have been reported worldwide. All tested cases contained high levels of elephant endotheliotropic herpesvirus (EEHV) DNA in pathological blood or tissue samples. Seven known major types of EEHVs have been partially characterized and shown to all belong to the novel Proboscivirus genus. However, the recently determined 206-kb EEHV4 genome proved to represent the prototype of a GC-rich branch virus that is very distinct from the previously published 180-kb EEHV1A, EEHV1B, and EEHV5A genomes, which all fall within an alternative AT-rich branch. Although EEHV4 retains the large family of 7xTM and vGPCR-like genes, six are unique to either just one or the other branch. While both branches display a highly enriched distribution of A and T tracts in intergenic domains, they are generally much larger within the GC-rich branch. Both branches retain the vGCNT1 acetylglucosamine transferase and at least one vOX-2 gene, but the two branches differ by 25 genes overall, with the AT-rich branch encoding a fucosyl transferase (vFUT9) plus two or three more vOX2 proteins and an immunoglobulin-like gene family that are all absent from the GC-rich branch. Several envelope glycoproteins retain only 15 to 20% protein identity or less across the two branches. Finally, the two plausible predicted transcriptional regulatory proteins display no homology at all to those in the alpha-, beta-, or gammaherpesvirus subfamilies. These results reinforce our previous proposal that the probosciviruses should be designated a new subfamily of mammalian herpesviruses.
KW - Acute hemorrhagic disease
KW - Elephant herpesviruses
KW - Evolutionary divergence
KW - Proposed Deltaherpesvirinae subfamily
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U2 - 10.1128/mSphere.00091-16
DO - 10.1128/mSphere.00091-16
M3 - Article
AN - SCOPUS:85041833744
SN - 2379-5042
VL - 1
JO - mSphere
JF - mSphere
IS - 3
M1 - e00091-16
ER -