Previous Article | Next Article ![]()
Journal of Virology, October 2008, p. 9477-9491, Vol. 82, No. 19
0022-538X/08/$08.00+0 doi:10.1128/JVI.00784-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Departments of Molecular Microbiology,1 Medicine and Pathology and Immunology, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, Missouri 63110-1093,2 W. Harry Feinstone Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe St., Suite E5132, Baltimore, Maryland 212053
Received 11 April 2008/ Accepted 10 July 2008
The severe acute respiratory syndrome coronavirus (SARS-CoV) ORF7b (also called 7b) protein is an integral membrane protein that is translated from a bicistronic open reading frame encoded within subgenomic RNA 7. When expressed independently or during virus infection, ORF7b accumulates in the Golgi compartment, colocalizing with both cis- and trans-Golgi markers. To identify the domains of this protein that are responsible for Golgi localization, we have generated a set of mutant proteins and analyzed their subcellular localizations by indirect immunofluorescence confocal microscopy. The N- and C-terminal sequences are dispensable, but the ORF7b transmembrane domain (TMD) is essential for Golgi compartment localization. When the TMD of human CD4 was replaced with the ORF7b TMD, the resulting chimeric protein localized to the Golgi complex. Scanning alanine mutagenesis identified two regions in the carboxy-terminal portion of the TMD that eliminated the Golgi complex localization of the chimeric CD4 proteins or ORF7b protein. Collectively, these data demonstrate that the Golgi complex retention signal of the ORF7b protein resides solely within the TMD.
Published ahead of print on 16 July 2008.
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»