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1.
Public Health ; 218: 60-67, 2023 May.
Article in English | MEDLINE | ID: mdl-36965465

ABSTRACT

OBJECTIVES: Cardiovascular health is the leading cause of death and disability in the United States. Our objective was to estimate the association between ideal cardiovascular health (ICVH) and multiple disabilities among US adults stratified into the three age groups of young (18-44 years), midlife (45-64 years), and older adults (≥65 years). STUDY DESIGN: We conducted a cross-sectional analysis using data pooled from the 2017 and 2019 Behavioral Risk Factor Surveillance System (BRFSS). METHODS: Using American Heart Association's seven-component (four ideal behaviors and three ideal health factors) scoring tool, we identified ICVH as a composite score ≥5 and also computed the ideal behavioral (score ≥3) and ideal health factors (score = 3) submetrics. The outcome, single vs multiple disabilities indicator, was defined using US Census's disability domains and analyzed using multinomial regression. RESULTS: For all three groups, the prevalence of multiple disabilities was significantly lower among those meeting ICVH, ideal behavioral, and ideal health factors compared with those that did not. After controlling for covariates, ICVH score ≥5 was associated with lower relative risk of multiple disabilities in all groups. Although both ideal health and ideal behavioral factors were associated with lower relative risk of multiple disabilities among all groups, the reduction in risk was the highest for multiple disabilities and ideal behavioral factors among midlife (relative risk ratio: 0.30, 95% confidence interval: 0.25, 0.36) and older adults (relative risk ratio: 0.40, 95% confidence interval: 0.33, 0.48). CONCLUSION: Adults with less-than-ideal cardiovascular health had a higher relative risk of multiple disabilities. Addressing the risk of multiple disabilities of US adults will require effective promotion of ICVH.


Subject(s)
Cardiovascular Diseases , Disabled Persons , Humans , United States/epidemiology , Aged , Adolescent , Young Adult , Adult , Behavioral Risk Factor Surveillance System , Cross-Sectional Studies , Cardiovascular Diseases/epidemiology , Risk Factors , Health Behavior
2.
J Exp Med ; 189(12): 1939-46, 1999 Jun 21.
Article in English | MEDLINE | ID: mdl-10377189

ABSTRACT

Gene expression patterns can provide vital clues to the pathogenesis of neoplastic diseases. We investigated the expression of 950 genes in Hodgkin's disease (HD) by analyzing differential mRNA expression using microarrays. In two independent microarray experiments, the HD-derived cell lines L428 and KMH2 were compared with an Epstein-Barr virus (EBV)-immortalized lymphoblastoid B cell line, LCL-GK. Interleukin (IL)-13 and IL-5 were found to be highly expressed in the HD-derived cell lines. Examination of IL-13 and IL-5 expression by Northern blot analysis and enzyme-linked immunosorbent assay confirmed these results and revealed the expression of IL-13 in a third HD-derived cell line, HDLM2. Control LCL and EBV-negative non-Hodgkin lymphoma-derived cell lines did not express IL-13. In situ hybridization of lymph node tissue from HD patients showed that elevated levels of IL-13 were specifically expressed by Hodgkin/Reed-Sternberg (H/RS) tumor cells. Treatment of a HD-derived cell line with a neutralizing antibody to IL-13 resulted in a dose-dependent inhibition of H/RS cell proliferation. These data suggest that H/RS cells produce IL-13 and that IL-13 plays an important role in the stimulation of H/RS cell growth, possibly by an autocrine mechanism. Modulation of the IL-13 signaling pathway may be a logical objective for future therapeutic strategies.


Subject(s)
Hodgkin Disease/immunology , Interleukin-13/metabolism , Reed-Sternberg Cells/immunology , Cell Division/drug effects , Gene Expression Regulation, Neoplastic , Genes, Neoplasm , Herpesvirus 4, Human/genetics , Hodgkin Disease/genetics , Hodgkin Disease/pathology , Humans , Immunohistochemistry , In Situ Hybridization , Interleukin-13/genetics , Interleukin-13/pharmacology , Interleukin-15/metabolism , Lymph Nodes/pathology , Lymphoma, Non-Hodgkin/genetics , RNA, Messenger/analysis , Reed-Sternberg Cells/pathology , Tumor Cells, Cultured
3.
Am J Respir Cell Mol Biol ; 18(1): 100-10, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9448051

ABSTRACT

Neutrophils and platelets interact both physically and metabolically during inflammation and thrombosis, but the mechanisms responsible for their adhesion remain incompletely understood. Neutrophil-platelet adhesion was measured after specific stimulation of neutrophils, platelets, or both and quantified by flow cytometry. Specific stimulation of either the neutrophil or the platelet led to a marked increase in the percentage of neutrophils that bound platelets, although platelet stimulation led to a large increase and neutrophil stimulation to only a small increase in the number of platelets per neutrophil. Stimulation of both cells further increased the number of neutrophil-platelet adhesive events and led to large numbers of platelets binding to each neutrophil. Confirming previous observations, blocking antibodies to platelet P-selectin (CD62P) partially inhibited adhesion. However, blockade of the neutrophil beta2 integrin CD11b/CD18 also inhibited the percentage of neutrophils that bound platelets. Combining P-selectin and CD11b/18 blockade further inhibited the stimulated increase in the percentage of neutrophils binding platelets and the increased number of platelets per neutrophil. Both cell adhesion molecules were active even when only a single cell type was primarily activated, supporting physiologically important transcellular activation. These data suggest that: (1) neutrophil-platelet adhesion can be initiated by specific activation of either the neutrophil or the platelet and that specific activation of either cell type leads to distinct patterns of adhesion, and (2) neutrophil-platelet adhesion uses both platelet P-selectin and the neutrophil beta2 integrin CD11b/CD18 when the cells are primarily or secondarily activated.


Subject(s)
Blood Platelets/physiology , CD18 Antigens/physiology , Cell Adhesion , Neutrophils/physiology , P-Selectin/physiology , Antibodies/pharmacology , Blood Platelets/ultrastructure , CD18 Antigens/immunology , Humans , Kinetics , Microscopy, Electron , N-Formylmethionine Leucyl-Phenylalanine/pharmacology , Neutrophils/ultrastructure , Oligopeptides/pharmacology , P-Selectin/immunology , Platelet Aggregation Inhibitors/pharmacology , Thrombin/pharmacology
4.
Scand J Gastroenterol ; 31(8): 786-91, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8858748

ABSTRACT

BACKGROUND: Neutrophils are significant effector cells in acute inflammatory bowel disease. Recruitment of these cells is dependent on beta 2-integrin-mediated adhesion and transmigration. The efficacy of neutrophil inhibitory factor (NIF), an antagonist of the beta 2-integrin CD11b/CD18, in ameliorating inflammation was tested in an animal model of acute colitis. METHOD: Immune-complex colitis was induced in groups of rabbits by using various formalin concentrations (2%, 0.75%, and 0.5%). Animals were treated with rNIF, 10 mg/kg. After they had been killed the mucosal appearance was scored, and tissue saved for histology and quantitation of myeloperoxidase (MPO), leukotriene B4 (LTB4), prostaglandin E2 (PGE2), and thromboxane B2 (TXB2). RESULTS: In the 2% formalin group therapy with rNIF resulted in lower LTB4 (p < 0.05) levels. For the 0.75% and 0.5% groups, MPO was lower with rNIF treatment (p < 0.03 and p < 0.05, respectively), as were LTB4 concentrations (both, p < 0.04). PGE2 and TXB2 levels remained unchanged. Histology showed polymorphonuclear cell infiltration to be reduced by rNIF in the 2% and 0.75% formalin-treatment groups (p < 0.05). CONCLUSION: These results suggest that blockade of CD11b/CD18-mediated mucosal neutrophil recruitment may form part of a strategy for targeted therapeutic intervention in inflammatory bowel disease.


Subject(s)
CD18 Antigens , Colitis/immunology , Glycoproteins/pharmacology , Helminth Proteins/pharmacology , Integrins/antagonists & inhibitors , Membrane Proteins , Acute Disease , Animals , Colitis/chemically induced , Colitis/metabolism , Colitis/pathology , Disease Models, Animal , Eicosanoids/metabolism , Formaldehyde , Male , Peroxidase/metabolism , Rabbits , Recombinant Proteins/pharmacology
6.
Gut ; 38(2): 201-5, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8801197

ABSTRACT

Crypt abscesses allow prolonged apposition of activated neutrophils to the epithelial surface of the colon. Adhesion of neutrophils to both the vascular endothelium and basolateral epithelial membrane share common effector molecules but are distinct processes. This study aimed to define the mechanisms that effect adhesion, independent of transmigration, to the apical epithelium. HT29 (cl 19A) cells were grown to confluency and incubated with neutrophils under conditions of: (i) neutrophil stimulation with phorbol-myristate-acetate; (ii) monolayer stimulation with interferon gamma, tumour necrosis factor alpha (IFN gamma, TNF alpha); and (iii) recent epithelial cell trypsinisation. These experiments were carried out in the presence of neutralising antibodies to CD18, CD11b, LFA-1, E-selectin, P-selectin, intracellular adhesion molecule 1 (ICAM-1), and ICAM-2; a novel CD11b/CD18 antagonist, neutrophil inhibitory factor (rNIF); adenosine receptor agonists (5'N-ethycarboxamido adenosine/N6-cylopentyladenosine (NECA/CPA)) and a platelet activating factor (PAF) receptor antagonist lexipafant. Adhesion of stimulated neutrophils to resting monolayers was Mac-1, CD18 dependent and ICAM-1, ICAM-2, E-selectin, P-selectin, PAF independent. Cytokine activated monolayers exhibited higher binding of neutrophils which was inhibited by rNIF and aCD18. Recently trypsinised monolayers bound neutrophils in a CD11b/CD18 and CD18 independent manner. Adenosine agonists failed to influence neutrophil adhesion under any condition. This study shows neutrophil adhesion to apical epithelial membranes is similar to that at the epithelial basolateral membrane, though different to that seen at the vascular endothelium. These results highlight regional differences in neutrophil adhesion molecule usage.


Subject(s)
Cell Adhesion Molecules/pharmacology , Cell Adhesion , Membrane Proteins , Neutrophils/drug effects , Cell Adhesion/drug effects , Clone Cells , Colonic Neoplasms/immunology , Glycoproteins/pharmacology , Helminth Proteins/pharmacology , Humans , Intercellular Adhesion Molecule-1/pharmacology , Lymphocyte Function-Associated Antigen-1/pharmacology , Neutrophil Activation , Neutrophils/physiology , Tumor Cells, Cultured
7.
J Leukoc Biol ; 59(2): 254-61, 1996 Feb.
Article in English | MEDLINE | ID: mdl-8603998

ABSTRACT

The CD11/CD18 leukocyte integrins are necessary for tissue localization of neutrophils, an early requisite event in inflammation. We have analyzed the contribution of CD11a/CD18 and CD11b/CD18 to local neutrophil accumulation and tissue injury in the reverse passive Arthus reaction in the rat dermis. Experimental groups comprised animals that received an intravenous infusion of (1) recombinant neutrophil inhibitory factor (NIF), a hookworm-derived antagonist of CD11b/CD18; (2) monoclonal antibody to CD11a/CD18 (TA-3); (3) a combination of these agents; (4) a monoclonal antibody to CD18 (WT.3); or (5) saline. Administration of recombinant NIF or anti-CD11a/CD18 monoclonal antibody alone produced a slight reduction in neutrophil accumulation but did not affect edema formation. In contrast, a combination of these antagonists yielded a significant reduction in neutrophil accumulation and a modest reduction in edema, equivalent to levels observed with either anti-CD18 antibodies or animals that were rendered neutropenic. These results indicate that neutrophil infiltration in rat dermal tissue in the reverse passive Arthus reaction is dependent predominantly on the leukocyte integrins CD11a/CD18 and CD11b/CD18 and that either of these integrins is sufficient for neutrophil trafficking in this inflammatory setting.


Subject(s)
Arthus Reaction/physiopathology , CD11 Antigens/physiology , CD18 Antigens/physiology , Dermatitis/physiopathology , Membrane Proteins , Animals , Antibodies, Monoclonal/pharmacology , Arthus Reaction/drug therapy , Arthus Reaction/pathology , CD11 Antigens/drug effects , CD11 Antigens/immunology , CD18 Antigens/drug effects , CD18 Antigens/immunology , CHO Cells , Cricetinae , Dermatitis/drug therapy , Dermatitis/pathology , Edema/drug therapy , Edema/immunology , Edema/pathology , Glycoproteins/pharmacology , Helminth Proteins/pharmacology , Male , Neutrophils/drug effects , Neutrophils/immunology , Neutrophils/pathology , Rabbits , Rats , Recombinant Proteins/pharmacology
8.
Ann Neurol ; 38(6): 935-42, 1995 Dec.
Article in English | MEDLINE | ID: mdl-8526467

ABSTRACT

We tested the neuroprotective potential of neutrophil inhibitory factor (rNIF), a novel 41-kd recombinant glycoprotein derived from a hookworm, in a model of focal cerebral ischemia in the rat. Male Wistar rats were assigned to treatment with rNIF and vehicle. Middle cerebral artery occlusion (MCAO) for 2 hours was induced by insertion of an intraluminal suture. Infusion of the drug was initiated at the onset of reperfusion. Infarct volume was determined 48 hours after reperfusion. Neutrophils were measured within the ischemic tissue by myeloperoxidase (MPO) staining. Treatment with rNIF resulted in a 48% reduction in cerebral infarction compared with control animals (p < 0.01). Neutrophil accumulation in the ischemic brains of rNIF-treated rats was reduced significantly (p < 0.01) compared with control animals. The number of neutrophils within the infarcted tissue correlated positively with the size of the area of infarction (p < 0.001, r = 0.6) within representative cerebral coronal sections. We demonstrated a significant neuroprotective effect of rNIF with continuous treatment for 48 hours following 2 hours of MCAO. The neuroprotective effect was correlated with a reduced number of neutrophils within the ischemic tissue. These results demonstrate potential therapeutic properties of rNIF in the management of stroke.


Subject(s)
Brain Ischemia/drug therapy , Glycoproteins/pharmacology , Helminth Proteins/pharmacology , Membrane Proteins , Neuroprotective Agents/pharmacology , Animals , Blood Gas Analysis , Body Weight , Glycoproteins/blood , Helminth Proteins/blood , Infusions, Intravenous , Leukocyte Count , Male , Neutrophils/cytology , Rats , Rats, Wistar , Recombinant Proteins/pharmacology , Reperfusion Injury/drug therapy , Reperfusion Injury/immunology , Temperature
9.
J Immunol ; 155(10): 4876-81, 1995 Nov 15.
Article in English | MEDLINE | ID: mdl-7594491

ABSTRACT

Neutrophil inhibitory factor (NIF) is a recently cloned 41-kDa protein from the canine hookworm that binds CD11b/CD18 and inhibits CD11b/CD18-dependent neutrophil adhesion. We evaluated NIF's effects on neutrophil-dependent lung injury in guinea pigs. Pulmonary vascular endothelial CD54 (ICAM-1) was induced in buffer-perfused lungs by 90-min exposure to 1000 U/ml TNF-alpha. Human neutrophils (2 x 10(7)) were added to the perfusate and activated by 5 x 10(-9) PMA; in some lungs, the neutrophils were pretreated with NIF (100 nM) before their addition to the perfusate. Lung injury was assessed by wet:dry weight ratio, and neutrophil uptake by lung myeloperoxidase (MPO) activity. HUVEC exposed to TNF-alpha for 90 min were assayed for neutrophil adhesion, and we compared PMA-stimulated neutrophil adhesion to endothelial cells and fibrinogen-coated plates. PMA-induced pulmonary edema (lung wet:dry ratio increased from 8.8 +/- 0.7 to 18.8 +/- 4.4) was inhibited by NIF (10.0 +/- 1.0). Lung MPO activity concomitantly decreased from 17.1 +/- 6.1 to 8.7 +/- 1.8 U/mg dry lung tissue in the NIF-treated group, similar to controls (6.9 +/- 2.0). Endothelial monolayer experiments confirmed that NIF reduced neutrophil adherence (basal adhesion of 11 +/- 3% increased to 30 +/- 5% with TNF-alpha pretreatment of endothelial cells, an increase that was reduced to 10 +/- 4% with NIF). Moreover, NIF prevented PMA-induced neutrophil adhesion to fibrinogen, a CD11b/CD18-dependent event, but produced a smaller decrease in adherence to endothelial cells, which also involves CD11a/CD18 integrins. These studies indicate that NIF prevents neutrophil-dependent lung vascular injury by inhibiting neutrophil adhesion to the TNF-alpha-activated endothelium.


Subject(s)
Endothelium/immunology , Glycoproteins/pharmacology , Helminth Proteins/pharmacology , Lung/immunology , Membrane Proteins , Neutrophil Activation , Neutrophils/immunology , Animals , Cell Adhesion/drug effects , Cells, Cultured , Dogs , Endothelium/pathology , Guinea Pigs , Humans , Intercellular Adhesion Molecule-1/immunology , Lung/pathology , Male , Neutrophils/pathology , Phorbol Esters/pharmacology , Tumor Necrosis Factor-alpha/pharmacology
10.
Shock ; 4(3): 187-92, 1995 Sep.
Article in English | MEDLINE | ID: mdl-8574753

ABSTRACT

This study was designed to assess the effect of neutrophil inhibitory factor (NIF), a novel specific inhibitor of CD11b/CD18 on hepatic leukocyte trafficking by intravital microscopy 5 h after hemorrhagic shock. Anesthetized rats were instrumented for invasive hemodynamical monitoring. Hemorrhagic shock was induced for 60 min by withdrawal of arterial blood (mean arterial blood pressure = 40 mmHg). Rats were adequately resuscitated for 5 h to achieve a mean arterial blood pressure > 100 mmHg and were randomly assigned to blinded treatment with NIF or placebo control protein administered as a single intravenous bolus (10 mg/kg) at the time of resuscitation. Intrahepatic leukocyte adhesion was evaluated by in vivo fluorescence microscopy. There were no significant differences observed in hemodynamic parameters between the shock groups throughout the study, however, NIF significantly reduced firm leukocyte adhesion in liver sinusoids. The results suggest that NIF may be beneficial in the attenuation of the pathological shock-induced leukocyte adhesion.


Subject(s)
CD18 Antigens/drug effects , Glycoproteins/therapeutic use , Helminth Proteins/therapeutic use , Leukocytes/drug effects , Liver/blood supply , Macrophage-1 Antigen/drug effects , Membrane Proteins , Shock, Hemorrhagic/drug therapy , Animals , Cell Adhesion/drug effects , Female , Hemodynamics/drug effects , Leukocytes/metabolism , Leukocytes/pathology , Liver/drug effects , Liver/pathology , Liver Circulation/drug effects , Rats , Rats, Sprague-Dawley , Shock, Hemorrhagic/pathology , Shock, Hemorrhagic/physiopathology
11.
J Biol Chem ; 269(42): 26419-23, 1994 Oct 21.
Article in English | MEDLINE | ID: mdl-7929363

ABSTRACT

Neutrophil inhibitory factor (NIF) is a hookworm-derived glycoprotein ligand of the integrin CD11b/CD18 that inhibits human neutrophil function (Moyle, M., Foster, D. L., McGrath, D. E., Brown, S. M., Laroche, Y., De Meutter, J., Stanssens, P., Bogowitz, C. A., Fried, V. A., Ely, J. A., Soule, H. R., and Vlasuk, G. P. (1994) J. Biol. Chem. 269, 1008-10015). Here, we present evidence that recombinant NIF (rNIF) associates with the approximately 200-amino acid residue I domain of CD11b/CD18 and that this interaction is essential for inhibition of neutrophil function by NIF. First, radiolabeled rNIF binds to a recombinant glutathione S-transferase fusion protein that contains the CD11b I domain. This high affinity interaction has a partial dependence on divalent cations. The association of rNIF with the CD11b I domain is specific because 125I-rNIF does not bind either a glutathione S-transferase fusion protein that contains the I domain of the integrin CD11a/CD18 or recombinant glutathione S-transferase without the I domain. Second, the CD11b I domain fusion protein effectively competes with CD11b/CD18 on human neutrophils for 125I-rNIF binding. Third, the CD11b I domain fusion protein blocks the inhibition of certain neutrophil functions by rNIF, including adhesion of neutrophils to human endothelial cell monolayers and adhesion-dependent release of hydrogen peroxide from neutrophils. Specificity is demonstrated by the inability of the CD11a I domain fusion protein to block either rNIF binding to neutrophils or rNIF activity. Fourth, rNIF blocks the interaction between neutrophils and fibrinogen, a CD11b/CD18 ligand that is also thought to bind the I domain of CD11b. In contrast, rNIF does not appear to block the binding of factor X to CD11b/CD18 on neutrophils. These results suggest that CD11b/CD18 has multiple distinct binding sites for its cognate ligands, including, but not limited to, the I domain. NIF interferes with the binding of a subset of these CD11b/CD18 ligands in a highly selective manner.


Subject(s)
Glycoproteins/metabolism , Helminth Proteins/metabolism , Integrins/antagonists & inhibitors , Macrophage-1 Antigen/metabolism , Membrane Proteins , Neutrophils/drug effects , Animals , Base Sequence , Binding Sites , CD11 Antigens/metabolism , CHO Cells , Cricetinae , Glycoproteins/pharmacology , Helminth Proteins/pharmacology , Molecular Sequence Data , Recombinant Proteins/metabolism
12.
J Biol Chem ; 269(13): 10008-15, 1994 Apr 01.
Article in English | MEDLINE | ID: mdl-7908286

ABSTRACT

The chronic survival of many endoparasites is dependent on the ability of these organisms to escape the host immune response. Identification of the molecular mechanisms by which these organisms evade this response may yield novel approaches in the development of anti-inflammatory agents. We describe here the discovery and characterization of a novel 41-kilodalton glycoprotein from the canine hookwork (Ancylostoma caninum) that potently inhibits CD11/CD18-dependent neutrophil function in vitro. Neutrophil inhibitory factor (NIF) blocks the adhesion of activated human neutrophils to vascular endothelial cells as well as the release of H2O2 from activated neutrophils, over a similar concentration range (IC50 10-20 nM). Studies aimed at determining the nature of the NIF binding site on neutrophils revealed selective, high affinity binding of this protein to the integrin CD11b/CD18. A cDNA encoding NIF was isolated from a canine hookworm cDNA library. NIF comprises a mature polypeptide of 257 amino acids, preceded by a 17-amino acid leader. The mature protein has 10 cysteines and has seven potential N-linked glycosylation sites. NIF has no significant sequence homologies to any previously reported protein. As such, NIF represents a prototype of a novel class of leukocyte function inhibitors.


Subject(s)
Ancylostomatoidea/physiology , Antigens, CD/metabolism , Glycoproteins/isolation & purification , Helminth Proteins/isolation & purification , Macrophage-1 Antigen/metabolism , Neutrophils/physiology , Amino Acid Sequence , Ancylostomatoidea/metabolism , Animals , Base Sequence , CD18 Antigens , Cloning, Molecular , DNA Primers , DNA, Complementary , Dogs , Glycoproteins/metabolism , Glycoproteins/pharmacology , Helminth Proteins/metabolism , Helminth Proteins/pharmacology , Humans , Leukocytes/drug effects , Leukocytes/physiology , Membrane Proteins/blood , Molecular Sequence Data , Neutrophils/drug effects , Neutrophils/immunology , Peptide Fragments/chemistry , Peptide Fragments/isolation & purification , Polymerase Chain Reaction , Protein Biosynthesis , Recombinant Proteins/metabolism , Recombinant Proteins/pharmacology
13.
J Biol Chem ; 266(29): 19650-8, 1991 Oct 15.
Article in English | MEDLINE | ID: mdl-1918072

ABSTRACT

Rabbit and human cDNA clones have been identified that encode a novel integrin beta subunit. The sequences that encode this subunit, which has been designated as beta 8, were isolated initially from rabbit placental cDNA libraries using an oligonucleotide probe derived from a highly conserved region of integrin beta subunit sequences. The rabbit clone was used to isolate human beta 8 cDNA clones from human placental and MG-63 osteosarcoma cell libraries. The putative beta 8 polypeptides, which comprise 769 and 768 residues in human and rabbit, respectively, show a high degree of inter-species conservation (approximately 90% identity). In contrast, beta 8 is distinct from the other integrin beta subunits. At the amino acid level human beta 8 ranges from 31 to 37% identity with human beta 1-7. The domain structure of beta 8 is typical of the integrin beta subunits. Human beta 8 has a 42-residue N-terminal signal peptide, a large extracellular domain (approximately 639 residues) that contains four cysteine-rich repeats, a transmembrane domain (approximately 30 residues), and a C-terminal cytoplasmic domain (approximately 58 residues). There are several structural features that are unique to the beta 8 polypeptide, as compared with the other integrin beta subunits. Six of the 56 cysteine residues that are conserved within the extracellular domains of beta 1, beta 2, beta 3, beta 5, beta 6, and the beta subunit from Drosophila are absent in the beta 8 polypeptide. Also, the cytoplasmic domain of the beta 8 subunit shares no homology with the cytoplasmic regions of any of the other integrin beta subunits. Northern analysis demonstrated an approximately 8-kilobase beta 8 mRNA in rabbit placenta, kidney, brain, ovary, and uterus. PCR analysis revealed that beta 8 mRNA is also present in several transformed human cell lines. The beta 8 polypeptide has been transiently expressed in 293 human embryonic kidney cells. A polyclonal antipeptide antibody specific for beta 8 and a polyclonal antibody that recognizes alpha v epitopes were used to show that beta 8 can complex with the endogenous alpha v subunit in 293 cells and that the resulting integrin is expressed as a cell surface complex.


Subject(s)
Integrins/genetics , Amino Acid Sequence , Animals , Base Sequence , Cell Line , Cloning, Molecular , Gene Expression , Humans , Molecular Sequence Data , RNA, Messenger/analysis , Rabbits , Restriction Mapping , Sequence Alignment , Transfection
14.
Mol Cell Biol ; 9(12): 5750-3, 1989 Dec.
Article in English | MEDLINE | ID: mdl-2685576

ABSTRACT

Monoclonal antibodies specific for the evolutionarily conserved C-terminal heptapeptide repeat domain of the largest subunit of RNA polymerase II inhibited the initiation of transcription from mammalian promoters in vitro. Since these antibodies did not inhibit elongation and randomly initiated transcription, the heptapeptide repeats may function by binding class II transcription initiation factor(s).


Subject(s)
RNA Polymerase II/metabolism , Transcription, Genetic , Amino Acid Sequence , Animals , Antibodies, Monoclonal , Cattle , Kinetics , Macromolecular Substances , Molecular Sequence Data , Promoter Regions, Genetic , RNA Polymerase II/genetics , RNA Polymerase II/immunology , Saccharomyces cerevisiae/enzymology , Thymus Gland/enzymology
15.
Mol Cell Biol ; 8(1): 321-9, 1988 Jan.
Article in English | MEDLINE | ID: mdl-3122024

ABSTRACT

Using DNA encoding the largest subunit of Drosophila melanogaster RNA polymerase II, we isolated the homologous hamster RPO21 gene. Nucleotide sequencing of both the hamster and D. melanogaster RPO21 DNAs confirmed that the RPO21 polypeptides of these two species, like the Saccharomyces cerevisiae RPO21 polypeptide, contain both an N-terminal region homologous to the Escherichia coli RNA polymerase subunit beta' and a unique polymerase II-specific C-terminal domain. This C-terminal domain, encoded by separate exons in the D. melanogaster and hamster genes, consists of a tandemly repeated heptapeptide sequence. By constructing a series of deletions in DNA encoding the 26 heptapeptide repeats normally present in the S. cerevisiae RPO21 polypeptide, we have established that a minimum of between 9 and 11 repeats is necessary for RPO21 function in yeast cells. Replacement of the yeast RPO21 heptapeptide repeats by the longer hamster repetitive domain resulted in viable yeast cells with no detectable mutant phenotype, while a similar replacement of the yeast repeats by the more divergent D. melanogaster repeats was a recessive lethal mutation. We suggest that this novel repetitive domain is essential for proper initiation of transcription by RNA polymerase II and that it may mediate the functions of TATA boxes, upstream activating sequences, and enhancers.


Subject(s)
Drosophila melanogaster/enzymology , RNA Polymerase II/physiology , Saccharomyces cerevisiae/enzymology , Amino Acid Sequence , Animals , Base Sequence , Cloning, Molecular , Cricetinae , DNA-Binding Proteins , Molecular Sequence Data , Species Specificity , Structure-Activity Relationship
16.
Biochem Cell Biol ; 64(8): 717-21, 1986 Aug.
Article in English | MEDLINE | ID: mdl-3021184

ABSTRACT

The 5' end of the RNA transcript of the Saccharomyces cerevisiae RNA polymerase related gene, RPO31, was localized on the RPO31 locus using Northern analyses and primer extension experiments. The amino terminal protein sequence was determined for the largest (relative mass approximately 160,000) subunit polypeptide of S. cerevisiae RNA polymerase III. The N-terminal amino acid sequence of this polypeptide was shown to be identical to that predicted for a putative RPO31 polypeptide initiated at the first ATG codon located 208-216 base pairs 3' to the major RPO31 mRNA start sites. The RPO31 locus thus encodes the largest subunit of S. cerevisiae RNA polymerase III.


Subject(s)
DNA-Directed RNA Polymerases/genetics , Genes, Fungal , RNA Polymerase III/genetics , Saccharomyces cerevisiae/enzymology , Amino Acid Sequence , DNA Restriction Enzymes , Deoxyribonuclease EcoRI , Nucleic Acid Hybridization , RNA, Fungal/genetics , Saccharomyces cerevisiae/genetics
17.
Cell ; 42(2): 599-610, 1985 Sep.
Article in English | MEDLINE | ID: mdl-3896517

ABSTRACT

We have determined the nucleotide sequence of two yeast RNA polymerase genes, RPO21 and RPO31, which encode the largest subunits of RNA polymerases II and III, respectively. The RPO21 and RPO31 sequences are homologous to each other, to the sequence of the largest subunit of E. coli RNA polymerase, and to sequences in the putative DNA-binding domain of E. coli DNA polymerase I. RPO21 has an unusual heptapeptide sequence tandemly repeated 26 times at its C-terminus; this sequence is conserved in the RNA polymerase II of higher eukaryotes and may play an important role in polymerase II-mediated transcription. Since eukaryotic and prokaryotic RNA polymerases appear to have evolved from a common ancestral polymerase, other features of the transcription process may also be evolutionarily conserved.


Subject(s)
DNA-Directed RNA Polymerases/genetics , Escherichia coli/enzymology , RNA Polymerase III/genetics , RNA Polymerase II/genetics , Saccharomyces cerevisiae/enzymology , Amino Acid Sequence , Base Sequence , Biological Evolution , DNA Polymerase I , DNA, Bacterial , DNA, Fungal , Escherichia coli/genetics , Genes, Bacterial , Genes, Fungal , Saccharomyces cerevisiae/genetics , Transcription, Genetic
18.
Australas Nurses J ; 7(10): 19-20, 1978 Jun.
Article in English | MEDLINE | ID: mdl-98147
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