Human immunodeficiency virus type 1 matrix protein assembles on membranes as a hexamer.
Article Details
- CitationCopy to clipboard
Alfadhli A, Huseby D, Kapit E, Colman D, Barklis E
Human immunodeficiency virus type 1 matrix protein assembles on membranes as a hexamer.
J Virol. 2007 Feb;81(3):1472-8. Epub 2006 Nov 15.
- PubMed ID
- 17108052 [ View in PubMed]
- Abstract
The membrane-binding matrix (MA) domain of the human immunodeficiency virus type 1 (HIV-1) structural precursor Gag (PrGag) protein oligomerizes in solution as a trimer and crystallizes in three dimensions as a trimer unit. A number of models have been proposed to explain how MA trimers might align with respect to PrGag capsid (CA) N-terminal domains (NTDs), which assemble hexagonal lattices. We have examined the binding of naturally myristoylated HIV-1 matrix (MyrMA) and matrix plus capsid (MyrMACA) proteins on membranes in vitro. Unexpectedly, MyrMA and MyrMACA proteins both assembled hexagonal cage lattices on phosphatidylserine-cholesterol membranes. Membrane-bound MyrMA proteins did not organize into trimer units but, rather, organized into hexamer rings. Our results yield a model in which MA domains stack directly above NTD hexamers in immature particles, and they have implications for HIV assembly and interactions between MA and the viral membrane glycoproteins.