Envelope glycoproteins are not required for insertion of host ICAM-1 into human immunodeficiency virus type 1 and ICAM-1-bearing viruses are still infectious despite a suboptimal level of trimeric envelope proteins.
Previous works have indicated that incorporation of surface glycoprotein into retroviruses such as the human immunodeficiency virus type 1 (HIV-1) is not a highly specific process because several cellular glycoproteins can be inserted within the mature viral particle. The mechanism(s) that govern the acquisition of such host constituents have remained so far elusive. In this study, we have investigated the role played by the viral envelope (Env) of HIV-1 in the acquisition of host intercellular adhesion molecule type I (ICAM-1). ICAM-1 proteins were still present on viruses carrying much lower levels of gp120/gp41 due to a mutation in the matrix (MA) domain or on Env-deficient viruses when produced in immortalized and primary human cell lines. Interestingly, infectivity of an HIV-1 MA mutant that carry a suboptimal amount of Env proteins was restored to a certain degree by the presence of ICAM-1 when infection was performed in cells expressing an activated form of its natural counter-ligand, LFA-1.
Beauséjour
Yannick
Y
Research Center in Infectious Diseases, CHUL Research Center, and Faculty of Medicine, Laval University, Quebec, Canada.
Tremblay
Michel J
MJ
D002460:Cell Line; D015699:HIV Envelope Protein gp120 / Q000737:chemistry / Q000502:physiology*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D018799:Intercellular Adhesion Molecule-1 / Q000502:physiology*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000502:physiology
D015699:HIV Envelope Protein gp120; D016169:Lymphocyte Function-Associated Antigen-1; D018799:Intercellular Adhesion Molecule-1