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Liao HX, Jia HY, Dai JR, Zong MH, Li N. Bioinspired Cooperative Photobiocatalytic Regeneration of Oxidized Nicotinamide Cofactors for Catalytic Oxidations. ChemSusChem 2021; 14:1615. [PMID: 33764662 DOI: 10.1002/cssc.202100471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Invited for this month's cover is the group of Ning Li at South China University of Technology. The image shows an efficient photobiocatalytic system to regenerate oxidized nicotinamide cofactors for dehydrogenase-mediated oxidations. The Communication itself is available at 10.1002/cssc.202100184.
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Affiliation(s)
- Huan-Xin Liao
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Hao-Yu Jia
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Jian-Rong Dai
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Min-Hua Zong
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Ning Li
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
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Liao HX, Jia HY, Dai JR, Zong MH, Li N. Bioinspired Cooperative Photobiocatalytic Regeneration of Oxidized Nicotinamide Cofactors for Catalytic Oxidations. ChemSusChem 2021; 14:1687-1691. [PMID: 33559949 DOI: 10.1002/cssc.202100184] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 02/05/2021] [Indexed: 06/12/2023]
Abstract
Inspired by water-forming NAD(P)H oxidases, a cooperative photobiocatalytic system has been designed to aerobically regenerate the oxidized nicotinamide cofactors. Photocatalysts enable NAD(P)H oxidation with O2 under visible-light irradiation, producing H2 O2 as a byproduct, which is subsequently used as an oxidant by the horseradish peroxidase mediator system (PMS) to oxidize NAD(P)H. The photobiocatalytic system shows a turnover frequency of 8800 min-1 in the oxidation of NAD(P)H. Photobiocatalytic NAD(P)H oxidation proceeds smoothly at pH 6-9. In addition to natural NAD(P)H, synthetic biomimetics are also good substrates for this regeneration system. Total turnover numbers of up to 180000 are obtained for the cofactor when the photobiocatalytic regeneration system is coupled with dehydrogenase-catalyzed oxidations. It may be a promising protocol to recycle the oxidized cofactors for catalytic oxidations.
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Affiliation(s)
- Huan-Xin Liao
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Hao-Yu Jia
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Jian-Rong Dai
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Min-Hua Zong
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
| | - Ning Li
- School of Food Science and Engineering, South China University of Technology, 381 Wushan Road, Guangzhou, 510640, P. R. China
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3
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Abstract
Signal joint T cell receptor delta (TCRD) excision circles (TRECs) are episomal DNA circles generated by the DNA recombination process that is used by T lymphocytes to produce antigen-specific alpha/beta T cell receptors. Measurement of TRECs in thymocytes and peripheral blood T cells has been used to study thymus output in chickens and humans. We have developed a real-time quantitative-PCR assay for the specific detection and quantification of mouse TCRD episomal DNA circles excised from the TCRA locus during TCRA gene rearrangement (mTRECs). We found that the mouse TCRD TRECs detected with this assay were predominantly in naïve phenotype CD4(+) and CD8(+) T cells. In a series of aged mice (range 6-90-week-old) we determined the absolute number of thymocytes and the number of molecules of mTRECs/100,000 thymocytes. We found that the absolute number of thymocytes dramatically decreased with age (P<0.05) and that molecules of mTREC/100,000 thymocytes also declined with mouse age (P<0.05). Splenocytes were isolated from aging mice and the frequency of naïve phenotype CD4 and CD8 cells determined. There was a significant drop in both CD4 and CD8 naïve peripheral T cells in the aged mice over time. mTREC analysis in purified CD4(+) and CD8(+) splenocytes demonstrated a constant level of mTRECs in the CD4 compartment until age 90 weeks, while the mTRECs in the CD8 compartment fell with age (P<0.05). By combining the mouse TREC assay with T cell phenotypic analysis, we demonstrated that IL-7 administration to young mice induced both increased thymopoiesis and peripheral T cell proliferation. In contrast, IL-7 treatment of aged mice did not augment thymopoiesis, nor induce expansion of splenic T cells. Thus, thymus output continues throughout murine adult life, and the thymic atrophy of aging in mice is not reversed by administration of IL-7.
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Affiliation(s)
- Gregory D Sempowski
- Department of Medicine, Center for AIDS Research, Human Vaccine Institute, Duke University Medical Center, Box 3258 Research Dr., Durham, NC 27710, USA.
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Staats HF, Bradney CP, Gwinn WM, Jackson SS, Sempowski GD, Liao HX, Letvin NL, Haynes BF. Cytokine requirements for induction of systemic and mucosal CTL after nasal immunization. J Immunol 2001; 167:5386-94. [PMID: 11673557 DOI: 10.4049/jimmunol.167.9.5386] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Cholera toxin (CT) is frequently used as an experimental adjuvant intranasally for the induction of systemic and mucosal immunity. However, CT is highly reactogenic and not approved for use in humans. To define the cytokine requirements for the nasal activation of the systemic and mucosal immune system, and to design new adjuvants with efficacy similar to CT, we defined the cytokines that were able to replace CT as a nasal adjuvant for the induction of CTL. BALB/c mice were nasally immunized with an HIV immunogen that contains an MHC class I-restricted CTL epitope +/- cytokines and tested for HIV-specific immune responses. We found that combinations of IL-1alpha plus IL-18, IL-1alpha plus IL-12, and IL-1alpha plus IL-12 plus GM-CSF each induced optimal splenocyte anti-HIV CTL responses in immunized mice (range 60-71% peptide-specific (51)Cr release). Peak H-2D(d)-peptide tetramer-binding T cell responses induced by cytokine combinations were up to 5.5% of CD8(+) PBMC. Nasal immunization with HIV immunogen and IL-1alpha, IL-12, and GM-CSF also induced Ag-specific IFN-gamma-secreting cells in the draining cervical lymph node and the lung. The use of IL-1alpha, IL-12, and GM-CSF as nasal adjuvants was associated with an increased expression of MHC class II and B7.1 on nonlymphocytes within the nasal-associated lymphoid tissue/nasal mucosa. Thus, IL-1alpha, IL-12, IL-18, and GM-CSF are critical cytokines for the induction of systemic and mucosal CTL after nasal immunization. Moreover, these cytokines may serve as effective adjuvants for nasal vaccine delivery.
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Affiliation(s)
- H F Staats
- Department of Medicine, Human Vaccine Institute, Duke University Medical Center, Durham, NC 27710, USA.
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Haynes BF, Liao HX, Staats HF, Alam MS, Weinhold KJ, Montefiori DC. HIV vaccine development at Duke University Medical Center. Immunol Res 2001; 22:263-9. [PMID: 11339361 DOI: 10.1385/ir:22:2-3:263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
With the AIDS epidemic continuing to spread throughout the world, development of a safe, practical, and effective HIV vaccine is a national priority. HIV vaccine research efforts are currently targeted towards design of HIV immunogens that induce both cellular and humoral immunity. This brief review summarizes ongoing work at the Duke University School of Medicine on HIV vaccine development.
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Affiliation(s)
- B F Haynes
- Department of Medicine, The Duke Center for Aids Research, Duke University Medical Center, Durham, NC 27710, USA.
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Tchilian EZ, Wallace DL, Imami N, Liao HX, Burton C, Gotch F, Martinson J, Haynes BF, Beverley PC. The exon A (C77G) mutation is a common cause of abnormal CD45 splicing in humans. J Immunol 2001; 166:6144-8. [PMID: 11342634 DOI: 10.4049/jimmunol.166.10.6144] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The leukocyte common (CD45) Ag is essential for normal T lymphocyte function and alternative splicing at the N terminus of the gene is associated with changes in T cell maturation and differentiation. Recently, a statistically significant association was reported in a large series of human thymus samples between phenotypically abnormal CD45 splicing and the presence of the CC chemokine receptor 5 deletion 32 (CCR5del32) allele, which confers resistance to HIV infection in homozygotes. We show here that abnormal splicing in these thymus samples is associated with the presence of the only established cause of CD45 abnormal splicing, a C77G transversion in exon A. In addition we have examined 227 DNA samples from peripheral blood of healthy donors and find no association between the exon A (C77G) and CCR5del32 mutations. Among 135 PBMC samples, tested by flow cytometric analysis, all those exhibiting abnormal splicing of CD45 also showed the exon A C77G transversion. We conclude that the exon A (C77G) mutation is a common cause of abnormal CD45 splicing and that further disease association studies of this mutation are warranted.
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Affiliation(s)
- E Z Tchilian
- Edward Jenner Institute for Vaccine Research, Compton, United Kingdom.
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Letvin NL, Robinson S, Rohne D, Axthelm MK, Fanton JW, Bilska M, Palker TJ, Liao HX, Haynes BF, Montefiori DC. Vaccine-elicited V3 loop-specific antibodies in rhesus monkeys and control of a simian-human immunodeficiency virus expressing a primary patient human immunodeficiency virus type 1 isolate envelope. J Virol 2001; 75:4165-75. [PMID: 11287566 PMCID: PMC114162 DOI: 10.1128/jvi.75.9.4165-4175.2001] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Vaccine-elicited antibodies specific for the third hypervariable domain of the surface gp120 of human immunodeficiency virus type 1 (HIV-1) (V3 loop) were assessed for their contribution to protection against infection in the simian-human immunodeficiency virus (SHIV)/rhesus monkey model. Peptide vaccine-elicited anti-V3 loop antibody responses were examined for their ability to contain replication of SHIV-89.6, a nonpathogenic SHIV expressing a primary patient isolate HIV-1 envelope, as well as SHIV-89.6P, a pathogenic variant of that virus. Low-titer neutralizing antibodies to SHIV-89.6 that provided partial protection against viremia following SHIV-89.6 infection were generated. A similarly low-titer neutralizing antibody response to SHIV-89.6P that did not contain viremia after infection with SHIV-89.6P was generated, but a trend toward protection against CD4+ T-lymphocyte loss was seen in these infected monkeys. These observations suggest that the V3 loop on some primary patient HIV-1 isolates may be a partially effective target for neutralizing antibodies induced by peptide immunogens.
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Affiliation(s)
- N L Letvin
- Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
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Liao HX, Montefiori DC, Patel DD, Lee DM, Scott WK, Pericak-Vance M, Haynes BF. Linkage of the CCR5 Delta 32 mutation with a functional polymorphism of CD45RA. J Immunol 2000; 165:148-57. [PMID: 10861047 DOI: 10.4049/jimmunol.165.1.148] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A 32-bp deletion in CCR5 (CCR5 Delta 32) confers to PBMC resistance to HIV-1 isolates that use CCR5 as a coreceptor. To study this mutation in T cell development, we have screened 571 human thymus tissues for the mutation. We identified 72 thymuses (12.6%) that were heterozygous and 2 (0.35%) that were homozygous for the CCR5 Delta 32 mutation. We found that thymocyte development was normal in both CCR5 Delta 32 heterozygous and homozygous thymuses. In 3% of thymuses we identified a functional polymorphism of CD45RA, in which cortical and medullary thymocytes failed to down-regulate the 200- and 220-kDa CD45RA isoforms during T cell development. Moreover, we found an association of this CD45 functional polymorphism in thymuses with the CCR5 Delta 32 mutation (p = 0.00258). In vitro HIV-1 infection assays with CCR5-using primary isolates demonstrated that thymocytes with the heterozygous CCR5 Delta 32 mutation produced less p24 than did CCR5 wild-type thymocytes. However, the functional CD45RA polymorphism did not alter the susceptibility of thymocytes to HIV-1 infection. Taken together, these data demonstrate association of the CCR5 Delta 32 mutation with a polymorphism in an as yet unknown gene that is responsible for the ability to down-regulate the expression of high m.w. CD45RA isoforms. Although the presence of the CCR5 Delta 32 mutation down-regulates HIV-1 infection of thymocytes, the functional CD45RA polymorphism does not alter the susceptibility of thymocytes to HIV-1 infection in vitro.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Cells, Cultured
- Child
- Child, Preschool
- Genetic Linkage
- HIV Infections/genetics
- HIV Infections/immunology
- Humans
- Immunity, Innate/genetics
- Immunophenotyping
- Infant
- Infant, Newborn
- Leukocyte Common Antigens/biosynthesis
- Leukocyte Common Antigens/genetics
- Leukocyte Common Antigens/physiology
- Leukocytes, Mononuclear/immunology
- Leukocytes, Mononuclear/metabolism
- Lymphocyte Subsets/immunology
- Lymphocyte Subsets/metabolism
- Lymphocyte Subsets/virology
- Middle Aged
- Mutation
- Organ Culture Techniques
- Polymorphism, Genetic
- Receptors, CCR5/biosynthesis
- Receptors, CCR5/genetics
- Thymus Gland/cytology
- Thymus Gland/immunology
- Thymus Gland/metabolism
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Affiliation(s)
- H X Liao
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA. '
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9
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Liao HX, Etemad-Moghadam B, Montefiori DC, Sun Y, Sodroski J, Scearce RM, Doms RW, Thomasch JR, Robinson S, Letvin NL, Haynes BF. Induction of antibodies in guinea pigs and rhesus monkeys against the human immunodeficiency virus type 1 envelope: neutralization of nonpathogenic and pathogenic primary isolate simian/human immunodeficiency virus strains. J Virol 2000; 74:254-63. [PMID: 10590113 PMCID: PMC111535 DOI: 10.1128/jvi.74.1.254-263.2000] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We have compared the abilities of human immunodeficiency virus type 1 (HIV-1) envelope V3 peptides and recombinant gp120 to induce antibodies that neutralize simian/human immunodeficiency viruses (SHIVs). SHIV-89.6 is a nonpathogenic SHIV that expresses the envelope protein of primary HIV-1 isolate 89.6. SHIV-89.6P, clone KB9, is a pathogenic SHIV variant derived from SHIV-89.6. Infection of rhesus monkeys with these SHIVs rarely induces anti-V3 region antibodies. To determine the availability of the gp120 V3 loop for neutralizing antibody binding on SHIV-89.6 and KB9 virions, we have constructed immunogenic C4-V3 peptides from these SHIVs and induced anti-V3 antibodies in guinea pigs and rhesus monkeys. We found that both SHIV-89.6 and KB9 C4-V3 peptides induced antibodies that neutralized SHIV-89.6 but that only SHIV-KB9 C4-V3 peptide induced antibodies that neutralized SHIV-KB9. Immunoprecipitation assays demonstrated that SHIV-KB9 C4-V3 peptide-induced antibodies had a greater ability to bind SHIV-KB9 envelope proteins than did antibodies raised against SHIV-89.6 C4-V3 peptide. We have used a series of mutant HIV-1 envelope constructs to map the gp120 determinants that affect neutralization by anti-V3 antibodies. The residue change at position 305 of arginine (in SHIV-89.6) to glutamic acid (in SHIV-KB9) played a central role in determining the ability of peptide-induced anti-V3 antiserum to neutralize primary isolate SHIVs. Moreover, residue changes in the SHIV-89.6 V1/V2 loops also played roles in regulating the availability of the V3 neutralizing epitope on SHIV-89.6 and -KB9. Thus, SHIV-89.6 and -KB9 V3 region peptides are capable of inducing neutralizing antibodies against these primary isolate SHIVs, although the pathogenic SHIV-KB9 is less easily neutralized than its nonpathogenic variant SHIV-89.6. In contrast to natural infection with SHIV-89.6, in which few animals make anti-V3 antibodies, C4-V3 peptides frequently induced anti-V3 antibodies that neutralized primary isolate SHIV strains.
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Affiliation(s)
- H X Liao
- Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710, USA
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10
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Haynes BF, Hale LP, Weinhold KJ, Patel DD, Liao HX, Bressler PB, Jones DM, Demarest JF, Gebhard-Mitchell K, Haase AT, Bartlett JA. Analysis of the adult thymus in reconstitution of T lymphocytes in HIV-1 infection. J Clin Invest 1999; 103:921. [PMID: 10079114 PMCID: PMC408144 DOI: 10.1172/jci5201e1] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Haynes BF, Hale LP, Weinhold KJ, Patel DD, Liao HX, Bressler PB, Jones DM, Demarest JF, Gebhard-Mitchell K, Haase AT, Bartlett JA. Analysis of the adult thymus in reconstitution of T lymphocytes in HIV-1 infection. J Clin Invest 1999; 103:453-60. [PMID: 10021452 PMCID: PMC408098 DOI: 10.1172/jci5201] [Citation(s) in RCA: 116] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A key question in understanding the status of the immune system in HIV-1 infection is whether the adult thymus contributes to reconstitution of peripheral T lymphocytes. We analyzed the thymus in adult patients who died of HIV-1 infection. In addition, we studied the clinical course of HIV-1 infection in three patients thymectomized for myasthenia gravis and determined the effect of antiretroviral therapy on CD4(+) T cells. We found that five of seven patients had thymus tissue at autopsy and that all thymuses identified had inflammatory infiltrates surrounding lymphodepleted thymic epithelium. Two of seven patients also had areas of thymopoiesis; one of these patients had peripheral blood CD4(+) T-cell levels of <50/mm3 for 51 months prior to death. Of three thymectomized patients, one rapidly progressed to AIDS, one progressed to AIDS over seven years (normal progressor), whereas the third remains asymptomatic at least seven years after seroconversion. Both latter patients had rises in peripheral blood CD4(+) T cells after antiretroviral therapy. Most patients who died of complications of HIV-1 infection did not have functional thymus tissue, and when present, thymopoiesis did not prevent prolonged lymphopenia. Thymectomy before HIV-1 infection did not preclude either peripheral CD4(+) T-cell rises or clinical responses after antiretroviral therapy.
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Affiliation(s)
- B F Haynes
- Department of Medicine, Duke Center for AIDS Research, Duke University Medical Center, Durham, North Carolina 27710, USA.
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12
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Weinberg J, Liao HX, Torres JV, Matthews TJ, Robinson J, Haynes BF. Identification of a synthetic peptide that mimics an HIV glycoprotein 120 envelope conformational determinant exposed following ligation of glycoprotein 120 by CD4. AIDS Res Hum Retroviruses 1997; 13:657-64. [PMID: 9168234 DOI: 10.1089/aid.1997.13.657] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
CD4 ligation of HIV envelope gp120 results in conformational changes in gp120 that lead to exposure of the gp41 fusogenic domain and fusion with the host cell membrane. One determinant at or near the CD4-binding site exposed on gp120 subsequent to CD4 binding is defined by two human MAbs termed 17b and 48d. These MAbs do not block CD4 binding to gp120; rather, their binding to gp120 is upregulated following CD4 binding. To determine if synthetic peptide mimetopes could be found that reflect conformational determinants on the surface of gp120, synthetic gp120 peptides from 10 divergent HIV isolates were screened for their ability to bind to 17b and 48d in ELISAs. Although MAb 48d binds to HIV IIIB recombinant gp120 protein, in our studies 48d selectively bound only to the HIV Can0A V3 peptide and not to HIV IIIB V3 peptide, whereas MAb 17b bound none of the peptides tested. Monoclonal antibody 48d bound to the HIV Can0A V3 peptide both in solid-phase ELISA and in solution in a competitive ELISA, but could not bind to HIV Can0A V3 peptide bound to human T cells. The HIV Can0A V3 peptide induced anti-HIV antibodies in rhesus monkeys that neutralized the laboratory-adapted HIV MN strain but did not induce antibodies that neutralized HIV IIIB/LAI, HIV SF-2, or HIV RF isolates, or that neutralized HIV primary isolates. These data suggested that the primary sequence of the HIV Can0A V3 loop exists in a conformer that mimicks a non-V3 determinant of native gp120 exposed subsequent to CD4 binding on the surface of gp120 of laboratory-adapted HIV strains. Structural studies of the Can0A V3 peptide and/or the 48d MAb may provide important information regarding the nature of gp120 conformational changes that occur following gp120 ligation by CD4.
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Affiliation(s)
- J Weinberg
- Department of Medicine, Center for AIDS Research, Duke University Medical Center, Durham, North Carolina 27710, USA
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13
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Abstract
The procedures summarized above provide nearly homogeneous preparations of IF-2mt, EF-Tu. Tsmt, and EF-Gmt. The scheme developed for IF-2mr leads to a 24,000-fold purification of this factor with a 26% recovery of activity. Analysis by SDS-polyacrylamide gel electrophoresis and gel filtration chromatography indicates that this factor functions as a monomer with a molecular weight of about 85,000. The scheme developed EF-Tu.Tsmt provides a 10,000-fold purification with an overall yield of about 10%. The EF-Tumt component in this complex has a molecular weight of about 46,000, whereas EF-Tsmt has a molecular weight of about 32,000 on SDS-polyacrylamide gel electrophoresis. The EF-Tu. Tsmt complex is tightly associated and appears to have a native molecular weight of about 70,000. The five-step purification procedure outlined above for EF-Gmt results in a 14,000-fold purification of EF-Gmt with a 2-5% recovery of activity. Analysis by SDS-polyacrylamide gel electrophoresis and gel filtration chromatography indicates that EF-Gmt functions as a monomeric protein with an apparent molecular weight of about 80,000.
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MESH Headings
- Animals
- Cattle
- Cell Fractionation/methods
- Chromatography/methods
- Chromatography, DEAE-Cellulose/methods
- Chromatography, Gel/methods
- Chromatography, High Pressure Liquid/methods
- Chromatography, Ion Exchange/methods
- Digitonin
- Durapatite
- Indicators and Reagents
- Liver/metabolism
- Liver/ultrastructure
- Mitochondria, Liver/metabolism
- Mitochondria, Liver/ultrastructure
- Peptide Chain Elongation, Translational
- Peptide Chain Initiation, Translational
- Peptide Elongation Factor 2
- Peptide Elongation Factor G
- Peptide Elongation Factor Tu/isolation & purification
- Peptide Elongation Factor Tu/metabolism
- Peptide Elongation Factors/isolation & purification
- Peptide Elongation Factors/metabolism
- Protein Biosynthesis
- RNA, Transfer, Amino Acyl/metabolism
- Ribosomes/metabolism
- Ribosomes/ultrastructure
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Affiliation(s)
- C J Schwartzbach
- Burroughs Wellcome Company. Research Triangle Park, North Carolina 27709, USA
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14
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Liao HX, Lee DM, Levesque MC, Haynes BF. N-terminal and central regions of the human CD44 extracellular domain participate in cell surface hyaluronan binding. The Journal of Immunology 1995. [DOI: 10.4049/jimmunol.155.8.3938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Abstract
CD44 molecules are cell surface receptors for hyaluronan (HA). To define regions of the extracellular domain of CD44 that are important for HA binding, we have studied the ability of HA-blocking CD44 mAbs to bind to CD44 from a variety of sources. Five CD44 mAbs (5F12, BRIC235, 3F12, BU-75, and HP2/9) of 21 studied were identified that at least partially blocked FITC-labeled HA (HA-FITC) binding to the standard form of CD44 (CD44S) in CD44-transfected Jurkat cells. Analysis of reactivity of HA-blocking CD44 mAbs defined three distinct epitopes. Lack of reactivity of mAb 5F12 with a CD44 fusion protein (CD44-Rg) containing an N-terminal truncation of 20 amino acids (aa), as well as reactivity of mAb 5F12 with an N-terminal CD44 synthetic peptide (CD44-9A), demonstrated that the N-terminal proximal region of CD44 (aa 1 to 20) was involved in mAb 5F12 binding. A mutant cell line, CEM-NKR, derived from the T-ALL cell line, CEM, did not bind mAb 5F12 nor bind HA, whereas wild-type CEM did bind mAb 5F12 and HA. Sequence analysis of wild-type CEM and CEM-NKR CD44 cDNA demonstrated a G to A point mutation at position 575 in the CD44 cDNA of CEM-NKR, resulting in an arginine to histidine mutation at aa position 154. Taken together, our studies demonstrated that there are three epitopes to which HA-blocking mAbs bind in the extracellular domain of CD44, and that the CD44 N-terminal proximal and central regions are two regions in the extracellular domain of CD44 that may interact and either mediate or regulate HA binding to cell surface CD44.
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Affiliation(s)
- H X Liao
- Department of Medicine, Duke Arthritis Center, Duke University Medical Center, Durham, NC 27710, USA
| | - D M Lee
- Department of Medicine, Duke Arthritis Center, Duke University Medical Center, Durham, NC 27710, USA
| | - M C Levesque
- Department of Medicine, Duke Arthritis Center, Duke University Medical Center, Durham, NC 27710, USA
| | - B F Haynes
- Department of Medicine, Duke Arthritis Center, Duke University Medical Center, Durham, NC 27710, USA
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15
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Liao HX, Lee DM, Levesque MC, Haynes BF. N-terminal and central regions of the human CD44 extracellular domain participate in cell surface hyaluronan binding. J Immunol 1995; 155:3938-45. [PMID: 7561101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
CD44 molecules are cell surface receptors for hyaluronan (HA). To define regions of the extracellular domain of CD44 that are important for HA binding, we have studied the ability of HA-blocking CD44 mAbs to bind to CD44 from a variety of sources. Five CD44 mAbs (5F12, BRIC235, 3F12, BU-75, and HP2/9) of 21 studied were identified that at least partially blocked FITC-labeled HA (HA-FITC) binding to the standard form of CD44 (CD44S) in CD44-transfected Jurkat cells. Analysis of reactivity of HA-blocking CD44 mAbs defined three distinct epitopes. Lack of reactivity of mAb 5F12 with a CD44 fusion protein (CD44-Rg) containing an N-terminal truncation of 20 amino acids (aa), as well as reactivity of mAb 5F12 with an N-terminal CD44 synthetic peptide (CD44-9A), demonstrated that the N-terminal proximal region of CD44 (aa 1 to 20) was involved in mAb 5F12 binding. A mutant cell line, CEM-NKR, derived from the T-ALL cell line, CEM, did not bind mAb 5F12 nor bind HA, whereas wild-type CEM did bind mAb 5F12 and HA. Sequence analysis of wild-type CEM and CEM-NKR CD44 cDNA demonstrated a G to A point mutation at position 575 in the CD44 cDNA of CEM-NKR, resulting in an arginine to histidine mutation at aa position 154. Taken together, our studies demonstrated that there are three epitopes to which HA-blocking mAbs bind in the extracellular domain of CD44, and that the CD44 N-terminal proximal and central regions are two regions in the extracellular domain of CD44 that may interact and either mediate or regulate HA binding to cell surface CD44.
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Affiliation(s)
- H X Liao
- Department of Medicine, Duke Arthritis Center, Duke University Medical Center, Durham, NC 27710, USA
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Liao HX, Haynes BF. Role of adhesion molecules in the pathogenesis of rheumatoid arthritis. Rheum Dis Clin North Am 1995; 21:715-40. [PMID: 8619096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The pathogenesis of rheumatoid arthritis centers on as yet unknown initiating events in the synovium that result in synovial vessel proliferation, and upregulation of endothelial cell ligands for leukocyte adhesion molecules. Ligation of adhesion molecules on synovial microenvironment cells and immune cells probably regulates synovial and immune cell inflammatory cytokine production. Interruption of adhesion molecule function and interruption of inflammatory cytokine production are promising new sites of therapeutic inhibition of synovial inflammation.
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Affiliation(s)
- H X Liao
- Department of Medicine, Duke University School of Medicine, Durham, NC 27710, USA
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17
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Dukes CS, Yu Y, Rivadeneira ED, Sauls DL, Liao HX, Haynes BF, Weinberg JB. Cellular CD44S as a determinant of human immunodeficiency virus type 1 infection and cellular tropism. J Virol 1995; 69:4000-5. [PMID: 7539503 PMCID: PMC189132 DOI: 10.1128/jvi.69.7.4000-4005.1995] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
CD4 is the predominant cell membrane protein that binds human immunodeficiency virus type 1 (HIV-1) gp120 and facilitates HIV-1 infection, but other membrane-associated molecules may be involved in determining HIV-1 cellular infection. Our prior work had suggested that CD44, the transmembrane receptor for hyaluronan, might play a role in the infection of mononuclear phagocytes with HIV-1. In the present work, we have used cells of the CD4-positive, CD44-negative human T-lymphoblast cell line Jurkat to study the role of CD44 in HIV-1 infection and tropism. Cells were transfected with cDNA for the standard (S, or hematopoietic) CD44 isoform CD44S or the epithelial isoform CD44E. The resultant lines expressed appropriate CD44S or CD44E mRNA and protein. While the parent Jurkat cells, those transfected with vector alone, and those transfected with CD44E could be productively infected with only the lymphocytotropic strain HIV-1-LAI, cells transfected with CD44S were rendered susceptible to productive infection with the monocytotropic strains HIV-1-BaL and HIV-1-ADA. Also, CD44S-transfected cells displayed higher levels of infection with HIV-1-LAI than did the other transfected Jurkat cells. The transfected cell line cells all had comparable growth rates and expressed similar levels of the membrane antigens CD4, CD7, major histocompatibility complex (MHC) class I, MHC class II, and CD11a, while levels of CD3 were slightly higher in cells transfected with vector alone and in one of the clones transfected with CD44S. Hyaluronan binding was increased in cells transfected with either CD44S or CD44E. Mouse NIH 3T3 fibroblasts transfected with human CD4, human CD44S, or both human CD4 and CD44S displayed the appropriate antigens, but they could not be productively infected with lymphocytotropic or monocytotropic strains of HIV-1. The results indicate that in human leukocytes, CD44S is an important determinant of HIV-1 productive infection and may be involved in viral cellular tropism.
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Affiliation(s)
- C S Dukes
- Department of Medicine, Veterans Affairs Medical Center, Durham, North Carolina 27705, USA
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Liao HX, Levesque MC, Patton K, Bergamo B, Jones D, Moody MA, Telen MJ, Haynes BF. Regulation of human CD44H and CD44E isoform binding to hyaluronan by phorbol myristate acetate and anti-CD44 monoclonal and polyclonal antibodies. J Immunol 1993; 151:6490-9. [PMID: 7504022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
CD44 molecules are comprised of multiple alternatively spliced forms and are associated with diverse functions such as mediation of carcinoma metastasis and T cell coactivation. To study the function of individual CD44 isoforms, we have transfected CD44 isoforms into CD44-negative Jurkat T cells and produced cloned Jurkat cell lines that are stably transfected with either a CD44 isoform containing no alternatively spliced insert (CD44H) or a CD44 variant (CD44E) containing an insert of 132 amino acids derived from exons 12, 13, and 14 of the CD44 gene. We found that neither CD44H- nor CD44E-transfected Jurkat T cells constitutively bound hyaluronan (HA), whereas PMA treatment induced Jurkat cells transfected with CD44H but not CD44E to bind HA. CD44 mAb against noninsert regions of the CD44 extracellular domain (A3D8, A1G3) and polyclonal antisera against the COOH-terminal extracellular glycosaminoglycan region of CD44H (anti-6A serum) both induced CD44H-transfected cells to bind HA, whereas only one CD44 mAb (A1G3) induced CD44E-transfected Jurkat T cells to bind HA. Studies of Jurkat cells transfected with CD44H forms with truncations of the CD44 cytoplasmic domain demonstrated that the cytoplasmic COOH-terminal 52 amino acids were critical for binding of HA to the CD44 extracellular domain. Thus, these data underscore the importance of the CD44 cytoplasmic domain in the function of the extracellular portion of CD44H, and demonstrate a role for ligation of human CD44 isoforms at multiple distinct sites in regulation of expression of CD44 binding to HA.
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Affiliation(s)
- H X Liao
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
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19
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Liao HX, Levesque MC, Patton K, Bergamo B, Jones D, Moody MA, Telen MJ, Haynes BF. Regulation of human CD44H and CD44E isoform binding to hyaluronan by phorbol myristate acetate and anti-CD44 monoclonal and polyclonal antibodies. The Journal of Immunology 1993. [DOI: 10.4049/jimmunol.151.11.6490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
CD44 molecules are comprised of multiple alternatively spliced forms and are associated with diverse functions such as mediation of carcinoma metastasis and T cell coactivation. To study the function of individual CD44 isoforms, we have transfected CD44 isoforms into CD44-negative Jurkat T cells and produced cloned Jurkat cell lines that are stably transfected with either a CD44 isoform containing no alternatively spliced insert (CD44H) or a CD44 variant (CD44E) containing an insert of 132 amino acids derived from exons 12, 13, and 14 of the CD44 gene. We found that neither CD44H- nor CD44E-transfected Jurkat T cells constitutively bound hyaluronan (HA), whereas PMA treatment induced Jurkat cells transfected with CD44H but not CD44E to bind HA. CD44 mAb against noninsert regions of the CD44 extracellular domain (A3D8, A1G3) and polyclonal antisera against the COOH-terminal extracellular glycosaminoglycan region of CD44H (anti-6A serum) both induced CD44H-transfected cells to bind HA, whereas only one CD44 mAb (A1G3) induced CD44E-transfected Jurkat T cells to bind HA. Studies of Jurkat cells transfected with CD44H forms with truncations of the CD44 cytoplasmic domain demonstrated that the cytoplasmic COOH-terminal 52 amino acids were critical for binding of HA to the CD44 extracellular domain. Thus, these data underscore the importance of the CD44 cytoplasmic domain in the function of the extracellular portion of CD44H, and demonstrate a role for ligation of human CD44 isoforms at multiple distinct sites in regulation of expression of CD44 binding to HA.
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Affiliation(s)
- H X Liao
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - M C Levesque
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - K Patton
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - B Bergamo
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - D Jones
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - M A Moody
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - M J Telen
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
| | - B F Haynes
- Department of Medicine, Duke University Medical Center, Durham, NC 27710
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Liao HX, Spremulli LL. Initiation of protein synthesis in animal mitochondria. Purification and characterization of translational initiation factor 2. J Biol Chem 1991; 266:20714-9. [PMID: 1939122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Bovine liver mitochondrial translational initiation factor 2 (IF-2mt) has been purified to near homogeneity. The scheme developed results in a 24,000-fold purification of the factor with about 26% recovery of activity. SDS-polyacrylamide gel electrophoresis indicates that IF-2mt has a subunit molecular mass of 85 kDa. IF-2mt promotes the binding of formyl(f)Met-tRNA to mitochondrial ribosomes but is inactive with the nonformylated derivative. IF-2mt is active on chloroplast 30 S ribosomal subunits, but IF-2chl has no activity in promoting fMet-tRNA binding to animal mitochondrial ribosomes. IF-2mt is sensitive to elevated temperatures and is inactivated by treatment with N-ethylmaleimide. It is partially protected from heat and N-ethylmaleimide inactivation by the presence of either GTP or GDP suggesting that guanine nucleotides may bind to this factor directly. The binding of fMet-tRNA to mitochondrial ribosomes requires the presence of GTP and is inhibited by GDP. DeoxyGTP is very effective in replacing GTP in promoting fMet-tRNA binding to ribosomes and some activity is also observed with ITP. No activity is observed with ATP, CTP, or UTP. Nonhydrolyzable analogs of GTP can promote formation of both 28 S and 55 S initiation complexes indicating that GTP hydrolysis is not required for subunit joining in the animal mitochondrial system.
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Affiliation(s)
- H X Liao
- Department of Chemistry, University of North Carolina, Chapel Hill 27599
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Kumazawa Y, Schwartzbach CJ, Liao HX, Mizumoto K, Kaziro Y, Miura K, Watanabe K, Spremulli LL. Interactions of bovine mitochondrial phenylalanyl-tRNA with ribosomes and elongation factors from mitochondria and bacteria. Biochim Biophys Acta 1991; 1090:167-72. [PMID: 1932108 DOI: 10.1016/0167-4781(91)90097-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A homologous in vitro poly(U)-directed translation system has been established using animal mitochondrial ribosomes, elongation factors (EF) and phenylalanyl-tRNA(Phe). The rate of incorporation of phenylalanine into polyphenylalanine in the mitochondrial system is slower than that observed for the homologous Escherichia coli system. E. coli ribosomes can be used in place of mitochondrial ribosomes in this system with only a slight decrease in the efficiency of phenylalanine incorporation from mitochondrial Phe-tRNA. However, E. coli elongation factor Tu (EF-Tu) cannot replace the mitochondrial EF-Tu in promoting the use of mitochondrial Phe-tRNA. The interaction between EF-Tu and mitochondrial Phe-tRNA was investigated by using the ability of EF-Tu to protect the aminoacyl-tRNA bond from hydrolysis. These results showed that both mitochondrial and E. coli EF-Tus are capable of interacting with mitochondrial Phe-tRNA. However, ribosomal A-site binding assays demonstrated that efficient binding of the mitochondrial Phe-tRNA to the ribosomal A-site was only obtained with the homologous mitochondrial EF-Tu.
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Affiliation(s)
- Y Kumazawa
- Department of Industrial Chemistry, Faculty of Engineering, University of Tokyo, Japan
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Liao HX, Spremulli LL. Identification and initial characterization of translational initiation factor 2 from bovine mitochondria. J Biol Chem 1990; 265:13618-22. [PMID: 2380177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The bovine liver mitochondrial factor that promotes the binding of fMet-tRNA to mitochondrial ribosomes, initiation factor 2 (IF-2mt), has been identified in the postribosomal supernatant fraction of isolated liver mitochondria. This factor has been purified approximately 5,000-fold and present preparations are estimated to be about 10% pure. IF-2mt has an apparent molecular weight of about 140,000 as determined by gel filtration chromatography. IF-2mt is active in stimulating fMet-tRNA binding to Escherichia coli ribosomes but E. coli IF-2 is not active in promoting initiator tRNA binding to animal mitochondrial ribosomes. The IF-2mt-mediated binding of fMet-tRNAi(Met) to mitochondrial ribosomes is dependent on the presence of a message such as poly(A,U,G) and on GTP. Nonhydrolyzable analogs of GTP are 2-3-fold less effective in promoting initiation complex formation on mitochondrial ribosomes than is GTP suggesting that IF-2mt is capable of recycling to some extent under the current assay conditions.
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Affiliation(s)
- H X Liao
- Department of Chemistry, University of North Carolina, Chapel Hill 27599-3290
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Liao HX, Spremulli LL. Effects of length and mRNA secondary structure on the interaction of bovine mitochondrial ribosomes with messenger RNA. J Biol Chem 1990; 265:11761-5. [PMID: 2365697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The mRNA for cytochrome oxidase subunit II (CoII) from bovine mitochondria binds to the small subunit of the mitochondrial ribosome in the absence of auxiliary factors. The synthetic polymer poly(U) is effective in competing with CoII mRNA for binding, although the polymer poly(A,U,G) competes very weakly. The effects of mRNA length on the interaction between the 28 S ribosomal subunit and mRNA have been examined using truncated derivatives of CoII mRNA. These results indicate that there is a minimum length of approximately 400 nucleotides required for the efficient binding of the mRNA to the small subunit. Shorter mRNAs will bind, but do so with much lower association constants. mRNAs of various lengths but with reduced secondary structure were prepared by substituting ITP for GTP during in vitro transcription reactions. These derivatives show the same effects of length as do the normal mRNA, indicating that RNA secondary structure is not a critical factor in subunit-mRNA interaction. The binding of the mRNA to the 28 S subunit is not influenced by the presence of guanine nucleotides or by the presence of a triphosphate at the 5' end of the RNA.
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Affiliation(s)
- H X Liao
- Department of Chemistry, University of North Carolina, Chapel Hill 27599-3290
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Liao HX, Spremulli LL. Interaction of bovine mitochondrial ribosomes with messenger RNA. J Biol Chem 1989; 264:7518-22. [PMID: 2540195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The gene for subunit II of cytochrome oxidase (CoII) from bovine mitochondria has been cloned behind a T7 promoter and the corresponding mRNA synthesized in vitro. The RNA transcribed from this vector has a single nucleotide 5' to the start AUG and, thus, corresponds closely to the native mRNA. It binds to the small 28 S ribosomal subunit of bovine mitochondria but not to the large (39 S) subunit or to 55 S ribosomes. The binding occurs readily in the absence of auxiliary initiation factors or initiator tRNA. The complex formed appears to contain 1 mRNA/28 S subunit. The observed binding is specific for mRNA since neither tRNA nor ribosomal RNA can act as competitive inhibitors. The interaction of the mRNA with the 28 S subunit does not require an AUG codon near the 5' end and constructs containing 5' leaders of more than 100 nucleotides still bind efficiently. About 5% of the bound mRNA is protected from digestion by T1 RNase. The protected fragments do not arise from a specific region of the mRNA since they hybridize to several restriction fragments of the cloned CoII gene.
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Affiliation(s)
- H X Liao
- Department of Chemistry, University of North Carolina, Chapel Hill 27599-3290
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Xing Z, Song G, Hang CS, Sugiyama K, Cheng BQ, Liao HX, Fu JL. [Antigenicity analysis of hemorrhagic fever with renal syndrome viruses by McAbs I]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 1987; 9:277-81. [PMID: 2450686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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27
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Xing Z, Song G, Sugiyama K, Su T, Liao HX, Fu JL, Chen BQ. [Detection of antigens and analysis of antigenicity of hemorrhagic fever with renal syndrome viruses by immune adherence hemagglutination assay (IAHA)]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 1986; 8:425-9. [PMID: 2954670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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Song G, Hang CS, Liao HX, Fu JL, Gao GZ, Qiu HL, Zhang QF. Antigenic difference between viral strains causing classical and mild types of epidemic hemorrhagic fever with renal syndrome in China. J Infect Dis 1984; 150:889-94. [PMID: 6150062 DOI: 10.1093/infdis/150.6.889] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The antigenic relationship between viral isolates from Apodemus and Rattus that appear to cause the classical and mild types of epidemic hemorrhagic fever (EHF) in China was studied by cross-immunofluorescence, cross-neutralization, immunofluorescence blocking tests, and cross-enzyme-linked immunosorbent assay (ELISA). Obvious antigenic diversity between the isolates was demonstrated by cross-neutralization, immunofluorescence blocking tests, and cross-ELISA. Antisera from patients with classical EHF neutralized viruses of both types to a similar degree, but antisera from patients with mild EHF showed little neutralization of apodemus virus. Similarly, antisera from classical EHF blocked immunofluorescence by monoclonal antibody (25-1 McAb) derived from apodemus virus to both viral antigens, but antisera from mild EHF gave only low-grade blocking against apodemus viral antigen. Direct antigenic titrations of both viral strains by cross-ELISA yielded similar results. That distinct antigenic differences exist between viral strains causing these two types of EHF might be of great importance to the serological differentiation of the viruses and the study of EHF vaccine.
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Hang CS, Fu JL, Liao HX, Gao GZ, Zhang QF, Qiu HL, Song G. [Studies on growth conditions of EHF virus in primary rat lung cell culture]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 1984; 6:353-5. [PMID: 6241087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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30
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Song G, Hang CS, Liao HX, Fu JL. Antigenic comparison of virus strains of mild and classical types of epidemic haemorrhagic fever isolated in China and adaptation of these to cultures of normal cells. Lancet 1984; 1:677-8. [PMID: 6142363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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31
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Hong T, Ye WW, Xia SM, Chu YL, Zhou JY, Zhao TX, Hang CS, Liao HX. [Identification of hemorrhagic fever-renal syndrome virus isolated from different areas in China by immuno-enzyme electron microscopy--morphological study on various virulent strains]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao 1983; 5:356-60. [PMID: 6233018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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32
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Song G, Hang CS, Qui XZ, Ni DS, Liao HX, Gao GZ, Du YL, Xu JK, Wu YS, Zhao JN, Kong BX, Wang ZS, Zhang ZQ, Shen HK, Zhou N. Etiologic studies of epidemic hemorrhagic fever (hemorrhagic fever with renal syndrome). J Infect Dis 1983; 147:654-9. [PMID: 6132949 DOI: 10.1093/infdis/147.4.654] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Two strains of epidemic hemorrhagic fever (EHF) virus were isolated from the lung tissues of Apodemus agrarius mice that were captured in an area where EHF is endemic. The strains were isolated by passages in A. agrarius mice from a nonendemic area. Identification of the isolates by usual procedures was confirmed by repeated blind tests with coded sera. Contamination with certain known viruses such as reovirus, adenovirus (types 3 and 7), and other pathogens, such as murine typhus rickettsiae and Leptospira, which may be naturally present in wild rodents, appeared to have been ruled out. The antigen slides made from these isolates are in use in the specific diagnosis and seroepidemiologic studies of EHF. The first successful application is the serodiagnosis of a mild type of hemorrhagic fever that occurs with characteristic epidemiologic features in certain provinces of China.
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Hung T, Xia SM, Song G, Liao HX, Chao TX, Chou ZY, Hang CS. Viruses of classical and mild forms of haemorrhagic fever with renal syndrome isolated in China have similar bunyavirus-like morphology. Lancet 1983; 1:589-91. [PMID: 6131283] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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