Abstract
Biological membrane fusion is an important part of many cellular processes and is a critical step in the entry of enveloped viruses, such as HIV-1, into cells. For HIV-1 to infect cells, the virus must bind to the cell surface, after which the viral Env protein must be triggered to undergo a conformational change that mediates membrane fusion. Cell-surface binding has long been known to occur via a high-affinity interaction between Env and CD4. However, the cell-surface molecules responsible for triggering the fusion-inducing conformational change in the Env protein have been only recently identified, permitting the study of HIV-1 Env-mediated membrane fusion in much greater detail (for review, see 1). These molecules, termed coreceptors, have been shown to be members of the nine-transmembrane domain receptor family. The most important HIV-1 coreceptors are the chemokine receptors CCR5 and CXCR4 (2–7), although at least nine other chemokine receptors or orphan receptors have been shown to support cellular entry for subsets of HIV-1 or SIV strains (3,5,8–11). The ability of a given virus strain to utilize particular chemokine receptors is a major determinant of cellular tropism. Thus, it is desirable to identify the receptors used by virus strains in a rapid, quantitative, and reproducible manner.
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Reference
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© 1999 Humana Press Inc., Totowa, NJ
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Edinger, A.L., Doms, R.W. (1999). A Cell-Cell Fusion Assay to Monitor HIV-1 Env Interactions with Chemokine Receptors. In: Michael, N.L., Kim, J.H. (eds) HIV Protocols. Methods in Molecular Medicine™, vol 17. Humana Press. https://doi.org/10.1385/0-89603-369-4:41
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DOI: https://doi.org/10.1385/0-89603-369-4:41
Publisher Name: Humana Press
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