| Structural highlights
Function
NS7A_SARS Plays a role as antagonist of host tetherin (BST2), disrupting its antiviral effect. Acts by binding to BST2 thereby interfering with its glycosylation. May suppress small interfering RNA (siRNA). May bind to host ITGAL, thereby playing a role in attachment or modulation of leukocytes.[1] [2] [3] [4]
Publication Abstract from PubMed
The open reading frame (ORF) 7a of the SARS-associated coronavirus (SARS-CoV) encodes a unique type I transmembrane protein of unknown function. We have determined the 1.8 A resolution crystal structure of the N-terminal ectodomain of orf7a, revealing a compact seven-stranded beta sandwich unexpectedly similar in fold and topology to members of the Ig superfamily. We also demonstrate that, in SARS-CoV- infected cells, the orf7a protein is expressed and retained intracellularly. Confocal microscopy studies using orf7a and orf7a/CD4 chimeras implicate the short cytoplasmic tail and transmembrane domain in trafficking of the protein within the endoplasmic reticulum and Golgi network. Taken together, our findings provide a structural and cellular framework in which to explore the role of orf7a in SARS-CoV pathogenesis.
Structure and intracellular targeting of the SARS-coronavirus Orf7a accessory protein.,Nelson CA, Pekosz A, Lee CA, Diamond MS, Fremont DH Structure. 2005 Jan;13(1):75-85. PMID:15642263[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Tan YJ, Fielding BC, Goh PY, Shen S, Tan TH, Lim SG, Hong W. Overexpression of 7a, a protein specifically encoded by the severe acute respiratory syndrome coronavirus, induces apoptosis via a caspase-dependent pathway. J Virol. 2004 Dec;78(24):14043-7. PMID:15564512 doi:http://dx.doi.org/10.1128/JVI.78.24.14043-14047.2004
- ↑ Hänel K, Willbold D. SARS-CoV accessory protein 7a directly interacts with human LFA-1. Biol Chem. 2007 Dec;388(12):1325-32. PMID:18020948 doi:10.1515/BC.2007.157
- ↑ Karjee S, Minhas A, Sood V, Ponia SS, Banerjea AC, Chow VT, Mukherjee SK, Lal SK. The 7a accessory protein of severe acute respiratory syndrome coronavirus acts as an RNA silencing suppressor. J Virol. 2010 Oct;84(19):10395-401. PMID:20631126 doi:10.1128/JVI.00748-10
- ↑ Taylor JK, Coleman CM, Postel S, Sisk JM, Bernbaum JG, Venkataraman T, Sundberg EJ, Frieman MB. Severe Acute Respiratory Syndrome Coronavirus ORF7a Inhibits Bone Marrow Stromal Antigen 2 Virion Tethering through a Novel Mechanism of Glycosylation Interference. J Virol. 2015 Dec;89(23):11820-33. PMID:26378163 doi:10.1128/JVI.02274-15
- ↑ Nelson CA, Pekosz A, Lee CA, Diamond MS, Fremont DH. Structure and intracellular targeting of the SARS-coronavirus Orf7a accessory protein. Structure. 2005 Jan;13(1):75-85. PMID:15642263 doi:http://dx.doi.org/S0969-2126(04)00384-3
|
