| CAR (for C&barbelow;oxsackievirus and A&barbelow;denovirus R&barbelow;eceptor) is a novel member of the Ig superfamily, which has recently been identified as a high affinity receptor for both Coxsackievirus and certain adenovirus (AV) serotypes. Virus bound by CAR is believed to be passed to integrins which bind an RGD (Arg-Gly-Asp) sequence in the viral penton base protein and act as secondary receptors responsible for virus internalization.;Recent studies have shown that, in integrin-expressing cells, CAR-mediated AV uptake does not require the cytoplasmic (CP) domain of CAR, presumably because virus bound to the CAR extracellular (EC) domain can be passed to integrins for subsequent internalization. It has however also been reported that CAR can directly mediate AV uptake in the absence of penton base RGD-alphav integrin interactions. I therefore attempted to determine whether the CP domain of CAR is required for CAR-mediated AV uptake in cells which do not express integrins, or in which integrin function has been blocked by RGD-containing peptide.;As CAR is the primary AV receptor and integrins are secondary AV receptors I investigated the possibility that these proteins associate in a functional complex in the cell membrane. (Abstract shortened by UMI.)... |
