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The association of the class II genes of the DRw10 haplotype from a cell line, NASC, initiated from a member of a well characterized family, was analyzed by sequencing cDNA clones corresponding to DR beta I, DQ alpha, and DQ beta genes. An identical haplotype was also identified in the Raji cell line. In addition to typing as DRw10 and DQw1 with HLA typing sera both, the NASC and Raji cell lines were shown to react strongly with the monoclonal antibodies 109d6 (specific for DRw10 beta 1 and DRw53 beta 2 gene products) and Genox 3.5.3 (specific for DQw1) and exhibited the restriction fragment length polymorphism indicative of a DRw10, DQw1 haplotype. The DR beta 1 gene corresponding to the DRw10 specificity was found to have a first domain sequence different from all other DR beta I genes. Sequence analysis of the 3'-untranslated region of this DR beta-chain gene showed a significant divergence from the 3' untranslated region of the DRw53 family of haplotypes and a lesser divergence from that of the DRw52 and DR1/DR2 families. The sequence of the DQ beta genes corresponding to the DQw1 specificity in the DRw10 haplotype was found to be identical to the DQ beta gene from a DR1, DQw1 haplotype. Surprisingly, however, the DQ alpha gene did not resemble other DQw1-like DQ alpha genes, but was identical in sequence to the DQ alpha gene found in DR4 haplotypes. The novel association of DQ alpha and DQ beta genes in the DRw10 haplotype revealed in these studies may result from a double recombinational event. More consequentially, these studies strongly suggest that the DQw1 specificity recognized by Genox 3.5.3 is determined by the DQ beta chain and is not affected by the DQ alpha-chain.  相似文献   
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Human interstitial retinoid binding protein (HIRBP) is a 136,000 m.w. photoreceptor cell protein which transports retinoids between the retina and the retinal pigment epithelium of the eye. The amino acid sequence of HIRBP suggests that the molecule consists of four continuous homology domains which arose by several gene duplications some 600 to 800 million years ago. When injected into susceptible animal species, including primates, it induces an experimental autoimmune uveitis (EAU), a predominantly T cell-mediated autoimmune disease of the retina and uveal tract of the eye, and the pineal gland. In order to further refine specific sites in HIRBP responsible for its uveitopathogenicity, we synthesized 120 overlapping peptide corresponding to its entire 1262 amino acid sequence, and tested each peptide for its ability to induce an EAU in Lewis rats. Five peptides with extensive amino acid sequence homology, designated HIRBP 715, HIRBP greater than 730 and HIRBP 745, HIRBP 778, and HIRBP 808 were uveitopathogenic when used at a 50 micrograms immunizing dose. The most potent peptide for the induction of EAU was HIRBP 715 (amino acid positions 521 to 540). In dose response studies as little as 0.1 microgram/animal was capable of inducing an inflammatory response. In addition, peptide HIRBP 946 which corresponds to the mid portion of peptide HIRBP 715 and contains only eight amino acids (RTATAAEE) was uveitopathogenic under our experimental conditions. Our study identifies multiple uveitopathogenic sites in HIRBP and further defines the amino acids necessary for the induction of EAU in one of these sites.  相似文献   
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S L Chuck  V R Lingappa 《Cell》1992,68(1):9-21
Previously, we described the stepwise translocation of a large amino-terminal fragment of apolipoprotein B (apo B15) in which the nascent secretory chain translocates through a series of distinct, nonintegrated transmembrane intermediates with large domains exposed to the cytoplasm. Thus, apo B15 appears to stop and restart translocation at several points. We have identified a sequence of amino acids in apo B15 that confers this behavior on a heterologous chimeric protein. In addition, we dissect pausing into two distinct steps, stopping and restarting, thereby trapping otherwise transient intermediates. Finally, we demonstrate the function of a second "pause transfer" sequence over 200 amino acids downstream in apo B15 that restarts translocation posttranslationally, suggesting that multiple pause transfer sequences are involved in the biogenesis of apolipoprotein B.  相似文献   
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Summary Serum specimens of three unrelated black males had an unusual alpha-1-antitrypsin phenotype, designated Pi Ecincinnati because of its electrophoretic mobility. Family studies indicated that the new phenotype was the expression of an alpha-1-antitrypsin allele, labeled Pi Ecincinnati  相似文献   
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The immune response of allophenic mice of type C57BL/6(A × SJL) F1 to GL administered in complete Freund's adjuvant was tested. Control mice of the three strains C57BL/6, A, and SJL are all nonresponders to this antigen. However, the F1 generations of C57BL/6 × A, C57BL/6 × SJL, and A × SJL were all responders to the antigen, so that the complementarity of at least two genes is confirmed. The allophenic mice showed no further complementation beyond the F1 generation, a result which may argue against the possibility that more than two genes control the response to GL in these mouse strains. Characterization of the allophenic mice over several months showed that they exhibit chimeric drift, both in their coat color and in peripheral white blood cell population. There is no apparent correlation of coat color to the lymphocyte composition of the mice at any one time. The mice are true chimeras, since killing of the two populations of white blood cells with two different anti-H-2 sera produced a 100 percent killing. The immune response of individual allophenic mice to GL showed a good correlation to the number of A × SJL lympho-cytes in the animal.Abbreviations used in this paper are GL an amino acid polymer of 57 %l-glutamic acid, 38%l-lysine, and 5%l-phenylalanine - GLT15 an amino acid polymer ofl-glutamic acid,l-lysine, and 15 %l-tyrosine - (T,G)-A-L an amino acid polymer having a polylysine backbone with side chains of polyd-l-alanine, terminating in short sequences of tyrosine and glutamic acid - GAT10 an amino acid polymer of 60%l-glutamic acid, 30%l-alanine, and 10%l-tyrosine - GLA5 an amino acid polymer of 57%l-glutamic acid, 38%l-lysine, and 5%l-alanine - DNP 2,4 dinitrophenyl - BGG bovine gamma globulin - FCS fetal calf serum - PWBC peripheral white blood cell - SWBC spleen white blood cell - T cell thymus-derived lymphocyte - B cell bone marrow-derived lymphocyte  相似文献   
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Kim Ki-duk's 2001 film Address Unknown presents a political allegory of modern Korea by referencing past traumas through local characters set in a U.S. military base town in 1970. The physical and emotional scars of past violence reveal current victimization re-enacting social injustice. Cold War militarism and the U.S. presence shatter the lives of three young people and the community as they internalize the destruction of their lives.  相似文献   
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Brain eicosapentaenoic acid (EPA) levels are 250- to 300-fold lower than docosahexaenoic acid (DHA), at least partly, because EPA is rapidly β-oxidized and lost from brain phospholipids. Therefore, we examined if β-oxidation was necessary for maintaining low EPA levels by inhibiting β-oxidation with methyl palmoxirate (MEP). Furthermore, because other metabolic differences between DHA and EPA may also contribute to their vastly different levels, this study aimed to quantify the incorporation and turnover of DHA and EPA into brain phospholipids. Fifteen-week-old rats were subjected to vehicle or MEP prior to a 5 min intravenous infusion of 14C-palmitate, 14C-DHA, or 14C-EPA. MEP reduced the radioactivity of brain aqueous fractions for 14C-palmitate-, 14C-EPA-, and 14C-DHA-infused rats by 74, 54, and 23%, respectively; while it increased the net rate of incorporation of plasma unesterified palmitate into choline glycerophospholipids and phosphatidylinositol and EPA into ethanolamine glycerophospholipids and phosphatidylserine. MEP also increased the synthesis of n-3 docosapentaenoic acid (n-3 DPA) from EPA. Moreover, the recycling of EPA into brain phospholipids was 154-fold lower than DHA. Therefore, the low levels of EPA in the brain are maintained by multiple redundant pathways including β-oxidation, decreased incorporation from plasma unesterified FA pool, elongation/desaturation to n-3 DPA, and lower recycling within brain phospholipids.  相似文献   
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