Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
EMBO J
1993 Nov 01;1211:4385-96. doi: 10.1002/j.1460-2075.1993.tb06123.x.
Show Gene links
Show Anatomy links
A novel type of class I gene organization in vertebrates: a large family of non-MHC-linked class I genes is expressed at the RNA level in the amphibian Xenopus.
???displayArticle.abstract???
A Xenopus class I cDNA clone, isolated from a cDNA expression library using antisera, is a member of a large family of non-classical class I genes (class Ib) composed of at least nine subfamilies, all of which are expressed at the RNA level. The subfamilies are well conserved in their immunoglobulin-like alpha 3 domains, but their peptide-binding regions (PBRs) and cytoplasmic domains are very divergent. In contrast to the great allelic diversity found in the PBR of classical class I genes, the alleles of one of the Xenopus non-classical subfamilies are extremely well conserved in all regions. Several of the invariant amino acids essential for the anchoring of peptides in the classical class I groove are not conserved in some subfamilies, but the class Ib genes are nevertheless more closely related in the PBR to classical and non-classical genes linked to the MHC in mammals and birds than to any other described class I genes like CD1 and the neonatal rat intestinal Fc receptor. Comparison with the Xenopus MHC-linked class Ia protein indicate that amino acids presumed to interact with beta 2-microglobulin are identical or conservatively changed in the two major class I families. Genomic analyses of Xenopus species suggest that the classical and non-classical families diverged from a common ancestor before the emergence of the genus Xenopus over 100 million years ago; all of the non-classical genes appear to be linked on a chromosome distinct from the one harboring the MHC. We hypothesize that this class Ib gene family is under very different selection pressures from the classical MHC genes, and that each subfamily may have evolved for a particular function.
Bjorkman,
Structure, function, and diversity of class I major histocompatibility complex molecules.
1990, Pubmed
Bjorkman,
Structure, function, and diversity of class I major histocompatibility complex molecules.
1990,
Pubmed Bjorkman,
The foreign antigen binding site and T cell recognition regions of class I histocompatibility antigens.
,
Pubmed Bradbury,
Mouse CD1 is distinct from and co-exists with TL in the same thymus.
1988,
Pubmed Briles,
A polymorphic system related to but genetically independent of the chicken major histocompatibility complex.
1993,
Pubmed Brodsky,
The cell biology of antigen processing and presentation.
1991,
Pubmed Brown,
A hypothetical model of the foreign antigen binding site of class II histocompatibility molecules.
1988,
Pubmed Chicz,
Predominant naturally processed peptides bound to HLA-DR1 are derived from MHC-related molecules and are heterogeneous in size.
1992,
Pubmed Feinberg,
A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity.
1983,
Pubmed Flajnik,
Which came first, MHC class I or class II?
1991,
Pubmed Flajnik,
Major histocompatibility complex-encoded class I molecules are absent in immunologically competent Xenopus before metamorphosis.
1986,
Pubmed
,
Xenbase Flajnik,
The major histocompatibility complex of frogs.
1990,
Pubmed Flajnik,
Evolution of the major histocompatibility complex: molecular cloning of major histocompatibility complex class I from the amphibian Xenopus.
1991,
Pubmed
,
Xenbase Guild,
Human and murine class I MHC antigens share conserved serine 335, the site of HLA phosphorylation in vivo.
1984,
Pubmed Guild,
HLA-A2 and HLA-B7 antigens are phosphorylated in vitro by rous sarcoma virus kinase (pp60v-src) at a tyrosine residue encoded in a highly conserved exon of the intracellular domain.
1983,
Pubmed Guillemot,
A molecular map of the chicken major histocompatibility complex: the class II beta genes are closely linked to the class I genes and the nucleolar organizer.
1988,
Pubmed Gyllensten,
Allelic diversity is generated by intraexon sequence exchange at the DRB1 locus of primates.
1991,
Pubmed Hashimoto,
Identification of a shark sequence resembling the major histocompatibility complex class I alpha 3 domain.
1992,
Pubmed Hedrick,
Dawn of the hunt for nonclassical MHC function.
1992,
Pubmed Hughes,
Pattern of nucleotide substitution at major histocompatibility complex class I loci reveals overdominant selection.
1988,
Pubmed Janeway,
The immune system evolved to discriminate infectious nonself from noninfectious self.
1992,
Pubmed Kaufman,
Different features of the MHC class I heterodimer have evolved at different rates. Chicken B-F and beta 2-microglobulin sequences reveal invariant surface residues.
1992,
Pubmed Klein,
Evolution of the major histocompatibility complex.
1986,
Pubmed Koller,
Cloning and complete sequence of an HLA-A2 gene: analysis of two HLA-A alleles at the nucleotide level.
1985,
Pubmed Kurlander,
Specialized role for a murine class I-b MHC molecule in prokaryotic host defenses.
1992,
Pubmed Latron,
A critical role for conserved residues in the cleft of HLA-A2 in presentation of a nonapeptide to T cells.
1992,
Pubmed Ljunggren,
In search of the 'missing self': MHC molecules and NK cell recognition.
1990,
Pubmed Madden,
The structure of HLA-B27 reveals nonamer self-peptides bound in an extended conformation.
1991,
Pubmed Martin,
Isolation of CD1 genes: a family of major histocompatibility complex-related differentiation antigens.
1986,
Pubmed Nei,
Simple methods for estimating the numbers of synonymous and nonsynonymous nucleotide substitutions.
1986,
Pubmed Pamer,
H-2M3 presents a Listeria monocytogenes peptide to cytotoxic T lymphocytes.
1992,
Pubmed Porcelli,
CD1b restricts the response of human CD4-8- T lymphocytes to a microbial antigen.
1992,
Pubmed Saitou,
The neighbor-joining method: a new method for reconstructing phylogenetic trees.
1987,
Pubmed Sanger,
DNA sequencing with chain-terminating inhibitors.
1977,
Pubmed Saper,
Refined structure of the human histocompatibility antigen HLA-A2 at 2.6 A resolution.
1991,
Pubmed Sato,
Evolution of the MHC: isolation of class II beta-chain cDNA clones from the amphibian Xenopus laevis.
1993,
Pubmed
,
Xenbase Simister,
An Fc receptor structurally related to MHC class I antigens.
1989,
Pubmed Watkins,
Evolution of the MHC class I genes of a New World primate from ancestral homologues of human non-classical genes.
1990,
Pubmed Wheeler,
Microconversion between murine H-2 genes integrated into yeast.
1990,
Pubmed
