Epstein-Barr virus BDLF2-BMRF2 complex affects cellular morphology.
Herpesvirus glycoproteins often form specific heterodimers that can fulfil functions that cannot be carried out by either of the partners acting alone. This study showed that interactions between the Epstein-Barr virus (EBV) multi-spanning transmembrane envelope protein BMRF2 and type II membrane protein BDLF2 influence the way in which these proteins are trafficked in the cell, and hence the subcellular compartment in which they accumulate. When expressed transiently in mammalian cells, BDLF2 accumulated in the endoplasmic reticulum (ER), whereas BMRF2 accumulated in the ER and Golgi apparatus. However, when the two proteins were co-expressed, BDLF2 was transported with BMRF2 to the Golgi apparatus and from there to the plasma membrane, where the proteins co-localized extensively. The distribution of the two proteins at the plasma membrane was reproducibly associated with dramatic changes in cellular morphology, including the formation of enlarged membrane protrusions and cellular processes whose adhesion extremities were organized by the actin cytoskeleton. A dominant-active form of the small GTPase RhoA was epistatic to this morphological phenotype, suggesting that RhoA is a central component of the signalling pathway that reorganizes the cytoskeleton in response to BDLF2-BMRF2. It was concluded that EBV produces a glycoprotein heterodimer that induces changes in cellular morphology through reorganization of the actin cytoskeleton and may facilitate virion spread between cells.
Loesing
Jens-Bernhard
JB
Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Forckenbeckstr. 6, 52074 Aachen, Germany.|Division of Virology, Department of Medical Microbiology, UK Aachen, RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany.
Di Fiore
Stefano
S
Institute for Molecular Biotechnology (IMB), RWTH Aachen, Worringerweg 1, 52074 Aachen, Germany.
Ritter
Klaus
K
Division of Virology, Department of Medical Microbiology, UK Aachen, RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany.
Fischer
Rainer
R
Fraunhofer Institute for Molecular Biology and Applied Ecology (IME), Forckenbeckstr. 6, 52074 Aachen, Germany.
Kleines
Michael
M
Division of Virology, Department of Medical Microbiology, UK Aachen, RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany.
D000818:Animals; D002460:Cell Line; D002462:Cell Membrane / Q000737:chemistry; D048430:Cell Shape; D003599:Cytoskeleton / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000737:chemistry; D006056:Golgi Apparatus / Q000737:chemistry; D004854:Herpesvirus 4, Human / Q000502:physiology*; D006801:Humans; D008322:Mammals; D008562:Membrane Glycoproteins / Q000378:metabolism*; D011485:Protein Binding; D014759:Viral Envelope Proteins / Q000378:metabolism*; D014764:Viral Proteins / Q000378:metabolism*; D020742:rhoA GTP-Binding Protein / Q000235:genetics / Q000502:physiology
C534105:BDLF2 protein, Epstein-Barr virus; C109482:BMRF-2 protein, Human herpesvirus 4; D008562:Membrane Glycoproteins; D014759:Viral Envelope Proteins; D014764:Viral Proteins; D020742:rhoA GTP-Binding Protein