The Transmembrane Domains of the prM and E Proteins of Yellow Fever Virus Are Endoplasmic Reticulum Localization Signals
AUTOR(ES)
Op De Beeck, Anne
FONTE
American Society for Microbiology
RESUMO
The immature flavivirus particle contains two envelope proteins, prM and E, that are associated as a heterodimer. Virion morphogenesis of the flaviviruses occurs in association with endoplasmic reticulum (ER) membranes, suggesting that there should be accumulation of the virion components in this compartment. This also implies that ER localization signals must be present in the flavivirus envelope proteins. In this work, we looked for potential subcellular localization signals in the yellow fever virus envelope proteins. Confocal immunofluorescence analysis of the subcellular localization of the E protein in yellow fever virus-infected cells indicated that this protein accumulates in the ER. Similar results were obtained with cells expressing only prM and E. Chimeric proteins containing the ectodomain of CD4 or CD8 fused to the transmembrane domains of prM or E were constructed, and their subcellular localization was studied by confocal immunofluorescence and by analyzing the maturation of their associated glycans. Although a small fraction was detected in the ER-to-Golgi intermediate and Golgi compartments, these chimeric proteins were located mainly in the ER. The C termini of prM and E form two antiparallel transmembrane α-helices. Interestingly, the first transmembrane passage contains enough information for ER localization. Taken altogether, these data indicate that, besides their role as membrane anchors, the transmembrane domains of yellow fever virus envelope proteins are ER retention signals. In addition, our data show that the mechanisms of ER retention of the flavivirus and hepacivirus envelope proteins are different.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=525104Documentos Relacionados
- Role of the Transmembrane Domains of prM and E Proteins in the Formation of Yellow Fever Virus Envelope
- Folding and Dimerization of Tick-Borne Encephalitis Virus Envelope Proteins prM and E in the Endoplasmic Reticulum
- Exchanging the Yellow Fever Virus Envelope Proteins with Modoc Virus prM and E Proteins Results in a Chimeric Virus That Is Neuroinvasive in SCID Mice
- Mutagenesis of the Signal Sequence of Yellow Fever Virus prM Protein: Enhancement of Signalase Cleavage In Vitro Is Lethal for Virus Production
- PrM- and Cell-Binding Domains of the Dengue Virus E Protein