Send to

Choose Destination
EMBO J. 2000 Oct 2;19(19):5081-91.

Membrane proteins organize a symmetrical virus.

Author information

Karolinska Institute, Department of Biosciences at Novum, S-141 57 Huddinge, Sweden.


Alphaviruses are enveloped icosahedral viruses that mature by budding at the plasma membrane. According to a prevailing model maturation is driven by binding of membrane protein spikes to a preformed nucleocapsid (NC). The T = 4 geometry of the membrane is thought to be imposed by the NC through one-to-one interactions between spike protomers and capsid proteins (CPs). This model is challenged here by a Semliki Forest virus capsid gene mutant. Its CPs cannot assemble into NCs, or its intermediate structures, due to defective CP-CP interactions. Nevertheless, it can use its horizontal spike-spike interactions on membrane surface and vertical spike-CP interactions to make a particle with correct geometry and protein stoichiometry. Thus, our results highlight the direct role of membrane proteins in organizing the icosahedral conformation of alphaviruses.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Wiley Icon for PubMed Central
Loading ...
Support Center