title: BTL-II: a polymorphic locus with homology to the butyrophilin gene family, located at the border of the major histocompatibility complex class II and class III regions in human and mouse.
abstract: Comparison of human and mouse genomic sequence at the border of the major histocompatibility complex (MHC) class II and class III regions revealed a locus encoding six exons with homology to the butyrophilin gene family and the location of a previously described gene, testis-specific basic protein (TSBP). We named the new locus BTL-II, for butyrophilin-like MHC class II associated. The six discernable exons of the BTL-II locus encode a small hydrophobic amino acid sequence (which may be a signal peptide), two immunoglobulin domains, a small 7-amino acid, heptad repeat-like exon, and a further two immunoglobulin domains. In mouse, an additional butyrophilin-like gene (NG10) is situated adjacent to BTL-II. Expression studies of the BTL-II locus in mouse showed that it is expressed in a range of gut tissues. We demonstrate that like many other genes from the MHC, BTL-II is polymorphic in a selection of diverse HLA haplotypes. In the light of the newly discovered locus, we revisit and discuss the possible origin of the butyrophilin gene family.
authors.affiliation: Sanger Centre, Wellcome Trust Genome Campus, Cambridge, UK.
authors.forename: M
authors.initials: M
authors.lastname: Stammers
authors.forename: L
authors.initials: L
authors.lastname: Rowen
authors.forename: D
authors.initials: D
authors.lastname: Rhodes
authors.forename: J
authors.initials: J
authors.lastname: Trowsdale
authors.forename: S
authors.initials: S
authors.lastname: Beck
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000071797:Butyrophilins; D003001:Cloning, Molecular; D005091:Exons; D005802:Genes, MHC Class II / Q000235:genetics*; D006801:Humans; D015212:Inflammatory Bowel Diseases / Q000209:etiology; D007422:Intestines; D008285:Major Histocompatibility Complex / Q000235:genetics*; D008562:Membrane Glycoproteins / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D005810:Multigene Family; D010802:Phylogeny; D011110:Polymorphism, Genetic; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D014018:Tissue Distribution
chemical_list: C408263:BTNL2 protein, human; D000071797:Butyrophilins; D008562:Membrane Glycoproteins