RT Journal Article
SR Electronic
T1 Novel Immunoglobulin Domain Proteins Provide Insights into Evolution and Pathogenesis Mechanisms of SARS-Related Coronaviruses
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2020.03.04.977736
DO 10.1101/2020.03.04.977736
A1 Yongjun Tan
A1 Theresa Schneider
A1 Matthew Leong
A1 L Aravind
A1 Dapeng Zhang
YR 2020
UL http://biorxiv.org/content/early/2020/03/07/2020.03.04.977736.abstract
AB A novel coronavirus (SARS-CoV-2) is the causative agent of an emergent severe respiratory disease (COVID-19) in humans that is threatening to result in a global health crisis. By using genomic, sequence, structural and evolutionary analysis, we show that Alpha- and Beta-CoVs possess several novel families of immunoglobulin (Ig) domain proteins, including ORF8 and ORF7a from SARS-related coronaviruses and two protein groups from certain Alpha-CoVs. Among them, ORF8 is distinguished in being rapidly evolving, possessing a unique insert and a hypervariable position among SARS-CoV-2 genomes in its predicted ligand-binding groove. We also uncover many Ig proteins from several metazoan viruses which are distinct in sequence and structure but share an architecture comparable to that of CoV Ig domain proteins. Hence, we propose that deployment of Ig domain proteins is a widely-used strategy by viruses, and SARS-CoV-2 ORF8 is a potential pathogenicity factor which evolves rapidly to counter the immune response and facilitate the transmission between hosts.