title: Novel leukocyte protein, Trojan, differentially expressed during thymocyte development.
abstract: "Trojan" is a novel cell surface protein, discovered from chicken embryonic thymocytes on the purpose to identify molecules involved in T cell differentiation. The molecule is predicted as a type I transmembrane protein having a Sushi and two fibronectin type III domains and a pair of intracellular phosphorylation sites. Its transcript expression is specific for lymphoid tissues and the presence of the protein on the surface of recirculating lymphocytes and macrophages was confirmed by immunofluorescence analysis. In thymus, about half of the double negative (CD4(-) CD8(-)) and CD8 single positive and the majority of CD4 single positive cells express Trojan with a relatively high intensity. However, only a minority of the double positive (CD4(+) CD8(+)) cells are positive for Trojan. This expression pattern, similar to that of some proteins with anti-apoptotic and function, like IL-7Ralpha, makes Trojan an attractive candidate of having an anti-apoptotic role.
authors.affiliation: Institute of Diagnostics, Department of Medical Microbiology, P.O. Box 5000, 90014 University of Oulu, Oulu, Finland. petar.petrov@oulu.fi
authors.forename: Petar
authors.initials: P
authors.lastname: Petrov
authors.forename: Maki
authors.initials: M
authors.lastname: Motobu
authors.forename: Jussi
authors.initials: J
authors.lastname: Salmi
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Uchida
authors.forename: Olli
authors.initials: O
authors.lastname: Vainio
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002454:Cell Differentiation; D002478:Cells, Cultured; D002645:Chickens / Q000276:immunology / Q000378:metabolism*; D018076:DNA, Complementary / Q000235:genetics; D005786:Gene Expression Regulation; D008214:Lymphocytes / Q000201:enzymology* / Q000276:immunology; D008264:Macrophages / Q000201:enzymology / Q000276:immunology; D008969:Molecular Sequence Data; D009928:Organ Specificity; D017027:Protein Tyrosine Phosphatases / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D013950:Thymus Gland / Q000737:chemistry / Q000166:cytology* / Q000201:enzymology* / Q000276:immunology
chemical_list: D018076:DNA, Complementary; D017027:Protein Tyrosine Phosphatases