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Lambracht-Washington D, Moore YF, Wonigeit K, Lindahl KF. Structure and expression of MHC class Ib genes of the central M region in rat and mouse: M4, M5, and M6. Immunogenetics 2008; 60:131-45. [PMID: 18324395 DOI: 10.1007/s00251-008-0282-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Accepted: 01/25/2008] [Indexed: 10/22/2022]
Abstract
The M region at the telomeric end of the murine major histocompatibility complex (MHC) contains class I genes that are highly conserved in rat and mouse. We have sequenced a cosmid clone of the LEW rat strain (RT1 haplotype) containing three class I genes, RT1.M6-1, RT1.M4, and RT1.M5. The sequences of allelic genes of the BN strain (RT1n haplotype) were obtained either from cDNAs or genomic clones. For the coding parts of the genes few differences were found between the two RT1 haplotypes. In LEW, however, only RT1.M5 and RT1.M6 have open reading frames; whereas in BN all three genes were intact. In line with the findings in BN, transcription was found for all three rat genes in several tissues from strain Sprague Dawley. Protein expression in transfectants could be demonstrated for RT1.M6-1 using the monoclonal antibody OX18. By sequencing of transcripts obtained by RT-PCR, a second, transcribed M6 gene, RT1.M6-2, was discovered, which maps next to RT1.M6-1 outside of the region covered by the cosmid. In addition, alternatively spliced forms for RT1.M5 and RT1.M6 were detected. Of the orthologous mouse genes, H2-M4, H2-M5, and H2-M6, only H2-M5 has an open reading frame. Other important differences between the corresponding parts of the M region of the two species are insertion of long LINE repeats, duplication of RT1.M6, and the inversion of RT1.M5 in the rat. This demonstrates substantial evolutionary dynamics in this region despite conservation of the class I gene sequences themselves.
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2
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Hansen TH, Huang S, Arnold PL, Fremont DH. Patterns of nonclassical MHC antigen presentation. Nat Immunol 2007; 8:563-8. [PMID: 17514210 DOI: 10.1038/ni1475] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The identification of pattern-recognition receptors that selectively respond to evolutionarily conserved chemical (often pathogen-derived) moieties has provided key insight into how innate immune cells facilitate rapid and relatively specific antimicrobial immune activity. In contrast, relatively slower adaptive immune responses rely on T cell clonal expansion that develops in response to variable peptides bound to the groove of classical major histocompatibility complex (MHC) proteins. For certain nonclassical 'MHC-like' class Ib proteins, such as H2-M3 and CD1d, their respective binding grooves seem to have been adapted to present to T cells unique molecular patterns analogous to those involved in innate signaling. Here we propose that another MHC class Ib protein, MR1, which is required for the gut flora-dependent development of mucosa-associated invariant T cells, presents either a microbe-produced or a microbe-induced pattern.
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Affiliation(s)
- Ted H Hansen
- Department of Pathology and Immunology, Washington University School of Medicine, Saint Louis, Missouri 63110, USA.
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3
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Joly E, Rouillon V. The orthology of HLA-E and H2-Qa1 is hidden by their concerted evolution with other MHC class I molecules. Biol Direct 2006; 1:2. [PMID: 16542007 PMCID: PMC1403747 DOI: 10.1186/1745-6150-1-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2006] [Accepted: 01/31/2006] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Whether MHC molecules undergo concerted evolution or not has been the subject of a long-standing debate. RESULTS By comparing sequences of eight functional homologues of HLA-E from primates and rodents with those of MHC class Ia molecules from the same eight species, we find that different portions of MHC class I molecules undergo different patterns of evolution. By focusing our analyses sequentially on these various portions, we have obtained clear evidence for concerted evolution of MHC class I molecules, suggesting the occurrence of extensive interallelic and intergenic exchanges. Intra-species homogenisation of sequences is particularly noticeable at the level of exon 4, which codes for the alpha3 domain, but our results suggest that homogenisation also concerns certain residues of the alpha1-alpha2 codomain that lie outside the antigen recognition site. CONCLUSION A model is presented in which Darwinian selective pressures due to pathogens could, at the same time, favour diversification of MHC class Ia molecules and promote concerted evolution of separate loci by spreading advantageous motifs arising by mutations in individual MHC molecules to other alleles and to other loci of the MHC region. This would also allow MHC molecules to co-evolve with the proteins with which they interact to fulfil their functions of antigen presentation and regulation of NK cell activity. One of the raisons d'être of the MHC may therefore be to favour at the same time both diversification of MHC class Ia molecules and homogenisation of the whole pool of MHC class I molecules (Ia and Ib) involved in antigen presentation. REVIEWERS This article was reviewed by Stephan Beck, Lutz Walter and Pierre Pontarotti.
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Affiliation(s)
- Etienne Joly
- Equipe de Neuro-Immuno-Génétique Moléculaire, IPBS, UMR CNRS 5089, 205 route de Narbonne, 31077 Toulouse Cedex, France
| | - Virginie Rouillon
- Equipe de Neuro-Immuno-Génétique Moléculaire, IPBS, UMR CNRS 5089, 205 route de Narbonne, 31077 Toulouse Cedex, France
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Moore YF, Lambracht-Washington D, Tabaczewski P, Fischer Lindahl K. Murine MHC class Ib gene, H2-M2, encodes a conserved surface-expressed glycoprotein. Immunogenetics 2004; 56:1-11. [PMID: 15045471 DOI: 10.1007/s00251-004-0661-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2003] [Revised: 02/21/2004] [Indexed: 11/30/2022]
Abstract
We have determined the genomic sequence of H2-M2 in seven haplotypes from nine inbred strains of mice and in five wild-derived haplotypes. Except for the spretus haplotype sp1 with a premature stop codon, we found only limited polymorphism. Four of the five amino acid substitutions in the alpha-helices are at positions that would point out from the antigen-binding groove, indicating that the polymorphism might influence receptor recognition rather than antigen binding. The rat homologue, RT1.M2(lv1), has 89% identity to H2-M2 at the nucleotide level and 91% at the amino acid level, and it also encodes an intact MHC class I glycoprotein. Chimeric proteins with alpha(1)alpha(2) or alpha(3)-transmembrane domains encoded by H2-Q9 were detectable on the surface of transfectants with monoclonal antibodies against Qa2, and the full-length M2 protein, labeled by fusion with green fluorescent protein, was detectable with S19.8 monoclonal antibodies. The H2-M2 protein was thus expressed on the cell surface, even in TAP-deficient RMA-S cells at 37 degrees C, suggesting that it is TAP-independent. We conclude that H2-M2 is a conserved mouse class Ib gene that is translated to a surface-expressed MHC class I molecule with a function still to be elucidated.
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Affiliation(s)
- Yuki F Moore
- Howard Hughes Medical Institute and Center for Immunology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9050, USA
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5
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Doyle CK, Davis BK, Cook RG, Rich RR, Rodgers JR. Hyperconservation of the N-formyl peptide binding site of M3: evidence that M3 is an old eutherian molecule with conserved recognition of a pathogen-associated molecular pattern. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2003; 171:836-44. [PMID: 12847252 DOI: 10.4049/jimmunol.171.2.836] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The mouse MHC class I-b molecule H2-M3 has unique specificity for N-formyl peptides, derived from bacteria (and mitochondria), and is thus a pathogen-associated molecular pattern recognition receptor (PRR). To test whether M3 was selected for this PRR function, we studied M3 sequences from diverse murid species of murine genera Mus, Rattus, Apodemus, Diplothrix, Hybomys, Mastomys, and Tokudaia and of sigmodontine genera Sigmodon and PEROMYSCUS: We found that M3 is highly conserved, and the 10 residues coordinating the N-formyl group are almost invariant. The ratio of nonsynonymous and synonymous substitution rates suggests the Ag recognition site of M3, unlike the Ag recognition site of class I-a molecules, is under strong negative (purifying) selection and has been for at least 50-65 million years. Consistent with this, M3 alpha1alpha2 domains from Rattus norvegicus and Sigmodon hispidus and from the "null" allele H2-M3(b) specifically bound N-formyl peptides. The pattern of nucleotide substitution in M3 suggests M3 arose rapidly from murid I-a precursors by an evolutionary leap ("saltation"), perhaps involving intense selective pressure from bacterial pathogens. Alternatively, M3 arose more slowly but prior to the radiation of eutherian (placental) mammals. Older dates for the emergence of M3, and the accepted antiquity of CD1, suggest that primordial class I MHC molecules could have evolved originally as monomorphic PRR, presenting pathogen-associated molecular patterns. Such MHC PRR molecules could have been preadaptations for the evolution of acquired immunity during the early vertebrate radiation.
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Affiliation(s)
- C Kuyler Doyle
- Baylor College of Medicine, Department of Immunology, Houston, TX 77030, USA
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6
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Crew MD, Bates LM. Sequence, expression, and polymorphism of the Peromyscus leucopus Mhc class Ib gene, M4. Immunogenetics 2003; 55:95-9. [PMID: 12700875 DOI: 10.1007/s00251-003-0569-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2003] [Revised: 03/18/2003] [Indexed: 10/25/2022]
Abstract
The H2 M region harbors about 20 class I genes or gene fragments the function of which are largely obscure. The rat Mhc ( RT1) appears to contain several orthologs of H2 M region genes although orthologs in more distantly related species have yet to be clearly identified. In this report, the sequence of a genomic clone containing a Peromyscus leucopus Mhc ( Pele) class I gene is presented and based on sequence similarity was found to be the Pele ortholog of H2-M4. Unlike H2-M4, which is a pseudogene, PeleM4 appeared to be an intact Mhc class Ib gene. Appropriately splice PeleM4 mRNA transcripts were detected in the liver, lung, and thymus. Polymorphism of PeleM4 was examined by sequencing exon 2 and 3 of the PeleM4 gene from seven different Pele haplotypes and six PeleM4 alleles were identified. These results suggest that the existence of some H2 M region class Ib genes predates the divergence of Peromyscus and Mus genera which occurred 40-60 million years ago and provide an example of unique pathways in the evolution of Mhc class Ib genes.
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Affiliation(s)
- Mark D Crew
- Central Arkansas Veterans Healthcare System and Departments of Microbiology and Immunology and Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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7
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Takada T, Kumánovics A, Amadou C, Yoshino M, Jones EP, Athanasiou M, Evans GA, Fischer Lindahl K. Species-specific class I gene expansions formed the telomeric 1 mb of the mouse major histocompatibility complex. Genome Res 2003; 13:589-600. [PMID: 12671000 PMCID: PMC430170 DOI: 10.1101/gr.975303] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We have determined the complete sequence of 951,695 bp from the class I region of H2, the mouse major histocompatibility complex (Mhc) from strain 129/Sv (haplotype bc). The sequence contains 26 genes. The sequence spans from the last 50 kb of the H2-T region, including 2 class I genes and 3 class I pseudogenes, and includes the H2-M region up to Gabbr1. A 500-kb stretch of the H2-M region contains 9 class I genes and 4 pseudogenes, which fall into two subfamilies, M1 and M10, distinct from other mouse class I genes. This M1/M10 class I gene-cluster is separated from the centromeric H2-T and the telomeric H2-M4, -5 and -6 class I genes by "nonclass I genes". Comparison with the corresponding 853-kb region of the human Mhc, which includes the HLA-A region, shows a mosaic of conserved regions of orthologous nonclass I genes separated by regions of species-specific expansion of paralogous Mhc class I genes. The analysis of this mosaic structure illuminates the dynamic evolution of the Mhc class I region among mammals and provides evidence for the framework hypothesis.
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Affiliation(s)
- Toyoyuki Takada
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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8
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Davis BK, Cook RG, Rich RR, Rodgers JR. Hyperconservation of the putative antigen recognition site of the MHC class I-b molecule TL in the subfamily Murinae: evidence that thymus leukemia antigen is an ancient mammalian gene. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 169:6890-9. [PMID: 12471122 DOI: 10.4049/jimmunol.169.12.6890] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
"Classical" MHC class I (I-a) genes are extraordinarily polymorphic, but "nonclassical" MHC class I (I-b) genes are monomorphic or oligomorphic. Although diversifying (positive) Darwinian selection is thought to explain the origin and maintenance of MHC class I-a polymorphisms, genetic mechanisms underlying MHC class I-b evolution are uncertain. In one extreme model, MHC class I-b loci are derived by gene duplication from MHC class I-a alleles but rapidly drift into functional obsolescence and are eventually deleted. In this model, extant MHC class I-b genes are relatively young, tend to be dysfunctional or pseudogenic, and orthologies are restricted to close taxa. An alternative model proposed that the mouse MHC class I-b gene thymus leukemia Ag (TL) arose approximately 100 million years ago, near the time of the mammalian radiation. To determine the mode of evolution of TL, we cloned TL from genomic DNA of 11 species of subfamily Murinae: Every sample we tested contained TL, suggesting this molecule has been maintained throughout murine evolution. The sequence similarity of TL orthologs ranged from 85-99% and was inversely proportional to taxonomic distance. The sequences showed high conservation throughout the entire extracellular domains with exceptional conservation in the putative Ag recognition site. Our results strengthen the hypotheses that TL has evolved a specialized function and represents an ancient MHC class I-b gene.
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Affiliation(s)
- Beckley K Davis
- Department of Immunology, Baylor College of Medicine, Houston, TX 77030, USA
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Ioannidu S, Walter L, Dressel R, Günther E. Physical map and expression profile of genes of the telomeric class I gene region of the rat MHC. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 166:3957-65. [PMID: 11238641 DOI: 10.4049/jimmunol.166.6.3957] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The rat is an important model for studying organ graft rejection and susceptibility to certain complex diseases. The MHC, the RT1 complex, plays a decisive role in controlling these traits. We have cloned the telomeric class I region of the RT1 complex, RT1-C/E/M, of the BN inbred rat strain in a contig of overlapping P1-derived artificial chromosome clones encompassing approximately 2 Mb, and present a physical map of this MHC region. Forty-five class I exon 4-hybridizing BAM:HI fragments were detected, including the previously known rat class I genes RT1-E, RT-BM1, RT1-N, RT1-M2, RT1-M3, and RT1-M4. Twenty-six non-class I genes known to map to the corresponding part of the human and mouse MHC were tested and could be fine mapped in the RT1-C/E/M region at orthologous position. Four previously known microsatellite markers were fine mapped in the RT1-C/E/M region and found to occur in multiple copies. In addition, a new, single-copy polymorphic microsatellite has been defined. The expression profiles of several class I genes and the 26 non-class I genes were determined in 13 different tissues and exhibited restricted patterns in most cases. The data provide further molecular information on the MHC for analyzing disease susceptibility and underline the usefulness of the rat model.
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Affiliation(s)
- S Ioannidu
- Division of Immunogenetics, University of Göttingen, Göttingen, Germany
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10
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Yuan XJ, Kunz HW, Gill TJ. Physical mapping and sequencing of class I genes in a 150-kb contig in the EC region. Transplant Proc 1999; 31:1507-12. [PMID: 10330984 DOI: 10.1016/s0041-1345(99)00020-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Affiliation(s)
- X J Yuan
- Department of Pathology, University of Pittsburgh School of Medicine, PA 15261, USA
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11
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Lambracht-Washington D, Wonigeit K, Lindahl KF. Gene order of the RT1.M region of the rat MHC exemplifies interspecies conservation with the mouse. Transplant Proc 1999; 31:1515-6. [PMID: 10330986 DOI: 10.1016/s0041-1345(99)00022-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- D Lambracht-Washington
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas 75235-9050, USA
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12
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Amadou C, Kumánovics A, Jones EP, Lambracht-Washington D, Yoshino M, Lindahl KF. The mouse major histocompatibility complex: some assembly required. Immunol Rev 1999; 167:211-21. [PMID: 10319263 DOI: 10.1111/j.1600-065x.1999.tb01394.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
We have assembled a contig of 81 yeast artificial chromosome clones that spans 8 Mb and contains the entire major histocompatibility complex (Mhc) from mouse strain C57BL/6 (H2b), and we are in the process of assembling an Mhc contig of bacterial artificial chromosome (BAC) clones from strain 129 (H2bc), which differs from C57BL/6 in the H2-Q and H2-T regions. The current BAC contig extends from Tapasin to D17Leh89 with gaps in the class II, H2-Q, and distal H2-M regions. Only four BAC clones were required to link the class I genes of the H2-Q and H2-T regions, and no new class I gene was found in the previous gap. The proximal 1 Mb of the H2-M region has been analyzed in detail and is ready for sequencing; it includes 21 class I genes or fragments, at least 14 olfactory receptor-like genes, and a number of non-class I genes that clearly establish a conserved synteny with the class I regions of the human and rat Mhc.
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Affiliation(s)
- C Amadou
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, USA
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13
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Gill TJ, Salgar SK, Yuan XJ, Kunz HW. Current status of the genetic and physical maps of the major histocompatibility complex in the rat. Transplant Proc 1997; 29:1657-9. [PMID: 9142220 DOI: 10.1016/s0041-1345(97)00003-1] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- T J Gill
- Department of Pathology, University of Pittsburgh School of Medicine, PA 15261, USA
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14
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Lambracht D, Wonigeit K, Howard JC, Fischer Lindahl K. Markers for interspecies relationship in the RT1 complex. Transplant Proc 1997; 29:1665-7. [PMID: 9142224 DOI: 10.1016/s0041-1345(97)00007-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- D Lambracht
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas 75235-9050, USA
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15
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Rolstad B, Vaage JT, Naper C, Lambracht D, Wonigeit K, Joly E, Butcher GW. Positive and negative MHC class I recognition by rat NK cells. Immunol Rev 1997; 155:91-104. [PMID: 9059885 DOI: 10.1111/j.1600-065x.1997.tb00942.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The prompt rejection of transplanted allogeneic lymphocytes by rat NK cells in non-sensitized recipients (allogeneic lymphocyte cytotoxicity or ALC) is determined by MHC genes as well as by genes located in the NK complex. The same genetic control is found when NK alloreactivity is measured by an in vitro assay, and we have employed this assay to delineate the specificity of NK cells for the MHC. The MHC of the rat, RT1, contains class I genes situated on either side of the class II/class III region. The majority of these class I genes are located in the RT1.C region and expressed class I products usually behave as non-classical (class Ib) molecules. They do not serve as restriction elements for the vast majority of conventional alpha/beta T-cells, in contrast to those class I molecules encoded by one or more loci in the classical (class Ia) region, RT1.A. However, NK cells appear to recognize the products of either class I region. Immunogenetic studies suggest that NK cells are inhibited by RT1. A molecules, whereas RT1.C region molecules may have a dual role in regulating NK cytolytic activity, i.e. they either inhibit or activate natural killing. Based on these premises, a model is proposed in which identification of a target as self or non-self depends on different receptors for class I in single NK cells, interpreting coincident positive and negative signals from the various target class I molecules. The putative role of peptides presented by class I, the biological implications, and the evolution of the NK receptors and their ligands are discussed.
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Affiliation(s)
- B Rolstad
- Immunology/Arthritis Section, Veterans Administration Medical Center, San Francisco, CA 94121, USA
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16
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Lindahl KF, Byers DE, Dabhi VM, Hovik R, Jones EP, Smith GP, Wang CR, Xiao H, Yoshino M. H2-M3, a full-service class Ib histocompatibility antigen. Annu Rev Immunol 1997; 15:851-79. [PMID: 9143709 DOI: 10.1146/annurev.immunol.15.1.851] [Citation(s) in RCA: 112] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
H2-M3 is an MHC class Ib molecule of the mouse with a unique preference for N-formylated peptides, which may come from the N-termini of endogenous, mitochondrial proteins or foreign, bacterial proteins. The crystal structure of M3 revealed a hydrophobic peptide-binding groove with an occluded A pocket and the peptide shifted one residue relative to class Ia structures. The formyl group is held by a novel hydrogen bonding network, involving His9 on the bottom of the groove, and the side chain of the P1 methionine is lodged in the B pocket. M3 is a full-service histocompatibility (H) antigen, i.e. self-M3 can present endogenous peptides as minor H antigens and foreign, bacterial antigens in a defensive immune response to infection; and foreign M3 complexed with endogenous self-peptides.
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Affiliation(s)
- K F Lindahl
- Howard Hughes Medical Institute, Departments of Microbiology and Biochemistry, University of Texas Southwestern Medical Center, Dallas 75235-9050, USA
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17
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Wang CR, Lindahl KF, Deisenhofer J. Crystal structure of the MHC class Ib molecule H2-M3. RESEARCH IN IMMUNOLOGY 1996; 147:313-21. [PMID: 8876059 DOI: 10.1016/0923-2494(96)89644-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- C R Wang
- Department of Pathology, Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, IL 60637-5420, USA
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18
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Yuan XJ, Salgar SK, Hassett AL, McHugh KP, Kunz HW, Gill TJ. Physical mapping of the E/C and grc regions of the rat major histocompatibility complex. Immunogenetics 1996; 44:9-18. [PMID: 8613150 DOI: 10.1007/bf02602652] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Alignment of class I-hybridizing cosmids from an R21 (AlBlDlEugrc+) genomic DNA library gave two contigs: one [150 kilobases (kb)] encompassed the E/C region, or a large part thereof, and the other (110 kb) contained the grc region which has genes influencing resistance to chemical carcinogens (rcc), fertility (ft), and growth (dw-3). Amplification of gene sequences in the four cosmids in the E/C region using Eu-specific and LW2 (RT1.C)-specific primers showed that each cosmid contained both Eu-like and C-like genes. They are clearly different but closely associated, and they show some variation from the prototypic E (Eu) and C (LW2) genes, respectively. Comparison of DNA from grc+ and grc- strains of rats showed that the deletion in the grc- strains was approximately 50 kb, and that it was located on two of the three cosmids in the grc-region contig. The use of specific class I probes showed that the grc region contained tandemly duplicated RT1.O-RT1.N genes and that the RT.BM1 loci lay outside of the grc region. Neither contig reacted with probes specific for class II, TNFA, Hsp70, or RT1.M genes. The data presented here and the previous data in the literature (summarized in Gill et al. 1995) suggest that the gene order in the major histocompatibility complex (MHC) and MHC-linked region of the rat is: A-E/C-grc-M.
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Affiliation(s)
- X J Yuan
- Department of Pathology, University of Pittsburgh, School of Medicine, PA, 15261, USA
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19
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Wang CR, Castaño AR, Peterson PA, Slaughter C, Lindahl KF, Deisenhofer J. Nonclassical binding of formylated peptide in crystal structure of the MHC class Ib molecule H2-M3. Cell 1995; 82:655-64. [PMID: 7664344 DOI: 10.1016/0092-8674(95)90037-3] [Citation(s) in RCA: 127] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
H2-M3 is a class Ib MHC molecule of the mouse with a 10(4)-fold preference for binding N-formylated peptides. To elucidate the basis of this unusual specificity, we expressed and crystallized a soluble form of M3 with a formylated nonamer peptide, fMYFINILTL, and determined the structure by X-ray crystallography. M3, refined at 2.1 A resolution, resembles class la MHC molecules in its overall structure, but differs in the peptide-binding groove. The A pocket, which usually accommodates the free N-terminus of a bound peptide, is closed, and the peptide is shifted one residue, such that the P1 side chain is lodged in the B pocket. The formyl group is coordinated by His-9 and a bound water on the floor of the groove.
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Affiliation(s)
- C R Wang
- Department of Biochemistry, University of Texas Southwestern Medical Center Dallas 75235-9050, USA
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