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EMBO J
1993 Nov 01;1211:4385-96. doi: 10.1002/j.1460-2075.1993.tb06123.x.
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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.
Flajnik MF
,
Kasahara M
,
Shum BP
,
Salter-Cid L
,
Taylor E
,
Du Pasquier L
.
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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,
The foreign antigen binding site and T cell recognition regions of class I histocompatibility antigens.
, Pubmed
Bjorkman,
The foreign antigen binding site and T cell recognition regions of class I histocompatibility antigens.
,
Pubmed
Bjorkman,
Structure, function, and diversity of class I major histocompatibility complex molecules.
1990,
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,
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
Flajnik,
Which came first, MHC class I or class II?
1991,
Pubmed
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
