title: A 13-amino-acid Pit1-specific loop 4 sequence confers feline leukemia virus subgroup B receptor function upon Pit2.
abstract: Feline leukemia virus subgroup B (FeLV-B) and gibbon ape leukemia virus (GALV) utilize the human protein Pit1 but not the related protein, Pit2, as receptor. A stretch of 9 amino acids, named region A, was identified in the putative fourth extracellular loop of Pit1 (residues 550 through 558) as critical for FeLV-B and GALV receptor function. However, the presence of Pit1 region A did not confer receptor function for FeLV-B upon Pit2, while it did so for GALV. We have here shown that the presence of two Pit1-specific loop 4 residues (tyrosine 546 and valine 548) in addition to Pit1 region A is sufficient to make Pit2 an efficient FeLV-B receptor; that is, a stretch of 13 amino acids encompassing all loop 4 amino acid differences between Pit1 and Pit2 comprises a C-terminal determinant for FeLV-B receptor function. Thus, the same limited receptor region is sufficient to confer receptor function for both viruses upon Pit2.
authors.affiliation: Department of Molecular and Structural Biology, University of Aarhus, DK-8000 Aarhus C, Denmark.
authors.forename: K
authors.initials: K
authors.lastname: Dreyer
authors.forename: F S
authors.initials: FS
authors.lastname: Pedersen
authors.forename: L
authors.initials: L
authors.lastname: Pedersen
mesh_terms: D016475:3T3 Cells; D000595:Amino Acid Sequence; D000596:Amino Acids; D000818:Animals; D001665:Binding Sites; D002415:Cats; D006801:Humans; D005256:Leukemia Virus, Feline / Q000378:metabolism*; D051379:Mice; D008969:Molecular Sequence Data; D011991:Receptors, Virus / Q000235:genetics / Q000378:metabolism* / Q000502:physiology
chemical_list: D000596:Amino Acids; D011991:Receptors, Virus; C067981:leukemia virus receptor, gibbon ape