Gpl20 protein chemokine interactions

Models also can assist in experimental design and the determination of the limits of experimental systems. For example, it is known that three proteins mediate the interaction of HIV with cells namely, the chemokine receptor CCR5, the cellular protein CD4, and the viral coat protein gpl20. An extremely useful experimental system to study this interaction is one in which radioactive CD4, prebound to soluble gpl20, is allowed to bind to cellular receptor CCR5. This system can be used to screen for... 

HIV enters the host cell by fusing the lipid membrane of the virus with the host cell membrane. This fusion is triggered by the interaction of proteins on the surface of the HIV envelope with specific cell surface receptors. One of these is CD4, the main receptor for HIV-1 that binds to gpl20, a surface protein on the virus particle.5 CD4 alone, however, is not sufficient to permit HIV fusion and cell entry-an additional co-receptor from the chemokine family of G-protein coupled receptors (GPCRs) is required. The chemokine receptor CCR5 has been demonstrated to be the major co-receptor for the... 

Like ASLV, HIV has a multistep mechanism for activation of membrane fusion. However, low pH is not required for HIV entry, and the virus instead uses a series of distinct interactions with components of the target membrane (reviewed in Dorns and Trono, 2000). The first interaction is with the CD4 protein. This binding event enables a subsequent contact between the HIV SU subunit gpl20 and a molecule of the chemokine receptor family (reviewed in Choe et al, 1998). It is this second interaction with molecules termed coreceptors that activates the membrane fusion potential of the TM subunit gp41 (reviewed in Berger et al, 1999). 

HIV entry into a cell requires the fusion of its viral envelope with the cell membrane. This normally occurs through an initial binding of the viral envelope protein, gpl20, to CD4, followed by a second interaction with a coreceptor, primarily chemokine receptor CXCR4 or CCR5 (Greene et al,... 

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