Spontaneous heteromerization of gammaretrovirus envelope proteins: a possible novel mechanism of retrovirus restriction.
The env gene of gammaretroviruses encodes a glycoprotein conserved among diverse retroviruses, except for the domains involved in receptor binding. Here we show that pairs of gammaretrovirus envelope proteins (from Friend virus and GALV or xenotropic viruses) assemble into heteromers when coexpressed. This assembly results in a strong inhibition of infectivity. An unrelated envelope protein does not assemble in heteromers with the gammaretrovirus glycoproteins tested and does not affect their infectivity, demonstrating the specificity of the mechanism we describe. We propose that the numerous copies of endogenous retroviral env genes conserved within mammalian genomes act as restriction factors against infectious retroviruses.
Dewannieux
Marie
M
Division of Infection and Immunity, University College London, Windeyer Building, 46 Cleveland St., London W1T 4JF, United Kingdom. m.dewannieux@ucl.ac.uk
Collins
Mary K
MK
D000595:Amino Acid Sequence; D002460:Cell Line; D017988:Gammaretrovirus / Q000378:metabolism*; D015686:Gene Products, env / Q000235:genetics*; D015752:Genes, env; D006023:Glycoproteins / Q000737:chemistry; D006801:Humans; D008957:Models, Genetic; D008969:Molecular Sequence Data; D011991:Receptors, Virus / Q000737:chemistry; D012190:Retroviridae / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D014162:Transfection; D014759:Viral Envelope Proteins / Q000737:chemistry*
D015686:Gene Products, env; D006023:Glycoproteins; D011991:Receptors, Virus; D014759:Viral Envelope Proteins