title: Variants of a Leishmania surface antigen derived from a multigenic family.
abstract: The promastigote surface antigen-2 (PSA-2) complex comprises a group of immunogenic surface antigens linked to the surface of the Leishmania major promastigote with glycosylphosphatidylinositol anchors. The L. major genome contains at least 14 PSA-2 genes on a 950-kilobase chromosome and comprising approximately 20% of the length of this chromosome. The sequence of three independent, but incomplete, PSA-2 cDNAs and one genomic fragment encoding a complete PSA-2 coding sequence were compared. PSA-2 genes encode polypeptides exhibiting 22-25aa tandem repeat elements, threonine-rich segments which vary between genes, a conserved COOH-terminal cysteine-rich region, and a conserved GPI anchor signal sequence. PSA-2 genes appear to be transcribed in a complex manner with multiple RNAs. The complex genomic organization of PSA-2 genes is present in other members of the genus suggesting that PSA-2 function is important for the biology of Leishmania.
authors.affiliation: Walter and Eliza Hall Institute of Medical Research, Melbourne, Victoria, Australia.
authors.forename: P J
authors.initials: PJ
authors.lastname: Murray
authors.forename: T W
authors.initials: TW
authors.lastname: Spithill
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics* / Q000276:immunology; D000954:Antigens, Surface / Q000235:genetics* / Q000276:immunology; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D016054:DNA, Protozoan; D016521:Electrophoresis, Gel, Pulsed-Field; D007891:Leishmania / Q000235:genetics / Q000276:immunology*; D008969:Molecular Sequence Data; D005810:Multigene Family; D009693:Nucleic Acid Hybridization; D015800:Protozoan Proteins; D016053:RNA, Protozoan / Q000235:genetics; D012091:Repetitive Sequences, Nucleic Acid; D016415:Sequence Alignment
chemical_list: D000953:Antigens, Protozoan; D000954:Antigens, Surface; D016054:DNA, Protozoan; D015800:Protozoan Proteins; D016053:RNA, Protozoan; C072094:surface antigen P2, Leishmania