Molecular characterization of fusion regulatory protein-1 (FRP-1) that induces multinucleated giant cell formation of monocytes and HIV gp160-mediated cell fusion. FRP-1 and 4F2/CD98 are identical molecules.
Fusion regulatory protein (FRP)-1 regulates virus-mediated cell fusion and fusion of monocytes. Eleven of fifteen N-terminal amino acids of FRP-1 were the same as the amino acid sequence of 4F2/CD98 heavy chain. FRP-1 molecules were detected in Con A- or IL-2-stimulated lymphocytes, while FRP-1 was rare on resting lymphocytes. These properties of FRP-1 are similar to those of 4F2/CD98. Treatment of monocytes with anti-4F2/CD98 mAbs resulted in cell fusion, and other mAbs directed against 4F2/CD98 induced formation of multinucleated giant cells of Cd+U2ME-7 cells, a CD4+U937 cell line transfected with the HIV gp160 gene. Both anti-4F2/CD98 and anti-FRP-1 mAbs reacted with murine L929 cells expressing human 4F2/CD98 transiently or constitutively. When Newcastle disease virus (NDV)-infected L929 cells expressing human FRP-1/CD98 were incubated with mAb 4-5-1, an anti-FRP-1 mAb, multinucleated giant cells were induced; thus, FRP-1/CD98 molecules expressed in L929 cells are functional for fusion regulatory activity.
Ohgimoto
S
S
Department of Microbiology, Mie University School of Medicine, Japan.
Tabata
N
N
Suga
S
S
Nishio
M
M
Ohta
H
H
Tsurudome
M
M
Komada
H
H
Kawano
M
M
Watanabe
N
N
Ito
Y
Y
D000595:Amino Acid Sequence; D015703:Antigens, CD / Q000737:chemistry* / Q000276:immunology; D001483:Base Sequence; D002459:Cell Fusion / Q000187:drug effects; D027261:Fusion Regulatory Protein-1; D015686:Gene Products, env / Q000494:pharmacology*; D015726:Giant Cells / Q000166:cytology / Q000276:immunology*; D019302:HIV Envelope Protein gp160; D006367:HeLa Cells; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000737:chemistry / Q000166:cytology* / Q000276:immunology; D008969:Molecular Sequence Data; D009000:Monocytes / Q000737:chemistry / Q000166:cytology* / Q000276:immunology; D011498:Protein Precursors / Q000494:pharmacology*; D014760:Viral Fusion Proteins / Q000737:chemistry* / Q000276:immunology
D015703:Antigens, CD; D027261:Fusion Regulatory Protein-1; D015686:Gene Products, env; D019302:HIV Envelope Protein gp160; D011498:Protein Precursors; D014760:Viral Fusion Proteins