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Breslow E. The neurophysins. ADVANCES IN ENZYMOLOGY AND RELATED AREAS OF MOLECULAR BIOLOGY 2006; 40:271-333. [PMID: 4599939 DOI: 10.1002/9780470122853.ch7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Geenen V, Martens H, Brilot F, Renard C, Franchimont D, Kecha O. Thymic neuroendocrine self-antigens. Role in T-cell development and central T-cell self-tolerance. Ann N Y Acad Sci 2001; 917:710-23. [PMID: 11268399 DOI: 10.1111/j.1749-6632.2000.tb05435.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The repertoire of thymic neuroendocrine precursors plays a dual role in T-cell differentiation as the source of either cryptocrine accessory signals in T-cell development or neuroendocrine self-antigens presented by the thymic major histocompatibility complex (MHC) machinery. Thymic neuroendocrine self-antigens usually correspond to peptide sequences highly conserved during the evolution of one family. The thymic presentation of some neuroendocrine self-antigens is not restricted by MHC alleles. Oxytocin (OT) is the dominant peptide of the neurohypophysial family. It is expressed by thymic epithelial and nurse cells (TEC/TNCs) of different species. Ontogenetic studies have shown that the thymic expression of the OT gene precedes the hypothalamic one. Both OT and VP stimulate the phosphorylation of p125FAK and other focal adhesion-related proteins in murine immature T cells. These early cell activation events could play a role in the promotion of close interactions between thymic stromal cells and developing T cells. It is established that such interactions are fundamental for the progression of thymic T-cell differentiation. Insulin-like growth factor 2 (IGF-2) is the dominant thymic polypeptide of the insulin family. Using fetal thymic organ cultures (FTOCs), the inhibition of thymic IGF-2-mediated signaling was shown to block the early stages of T-cell differentiation. The treatment of FTOCs with an mAb anti-(pro)insulin had no effect on T-cell development. In an animal model of autoimmune type 1 diabetes (BB rat), thymic levels of (pro)insulin and IGF-1 mRNAs were normal both in diabetes-resistant and diabetes-prone BB rats. IGF-2 transcripts were clearly identified in all thymuses from diabetes-resistant adult (5-week) and young (2- and 5-days) BB rats. In marked contrast, the IGF-2 transcripts were absent and the IGF-2 protein was almost undetectable in +/- 80% of the thymuses from diabetes-prone adult and young BB rats. These data show that a defect of the thymic IGF-2-mediated tolerogenic function might play an important role in the pathophysiology of autoimmune Type 1 diabetes.
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Affiliation(s)
- V Geenen
- Department of Medicine, Institute of Pathology CHU-B23, Laboratory of Radio-Immunology and Neuroendocrine-Immunology, University of Liège, Belgium.
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Geenen V, Kecha O, Martens H. Thymic expression of neuroendocrine self-peptide precursors: role in T cell survival and self-tolerance. J Neuroendocrinol 1998; 10:811-22. [PMID: 9831257 DOI: 10.1046/j.1365-2826.1998.00269.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- V Geenen
- Department of Medicine, Institute of Pathology CHU-1323, University of Liège, Belgium.
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Martens H, Goxe B, Geenen V. The thymic repertoire of neuroendocrine self-antigens: physiological implications in T-cell life and death. IMMUNOLOGY TODAY 1996; 17:312-7. [PMID: 8763816 DOI: 10.1016/0167-5699(96)10023-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Affiliation(s)
- H Martens
- University of Liège Medical School, Institute of Pathology CHU-B23, Sart Tilman, Belgium
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GEENEN VINCENT, CORMANN NADINE, VANDERSMISSEN ERIC, MARTENS HENRI, BENHIDA ABDELLAH, MARTIAL JOSEPH, FRANCHIMONT PAUL. Cryptocrine Signaling in the Thymus Network. Ann N Y Acad Sci 1994. [DOI: 10.1111/j.1749-6632.1994.tb23089.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Huang HB, Wellner D, Naudé R, Oelofsen W, Oosthuizen MM, Breslow E. Amino acid sequence and properties of vasopressin-associated elephant neurophysin. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1994; 44:270-7. [PMID: 7822104 DOI: 10.1111/j.1399-3011.1994.tb00170.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The primary structure of an elephant neurophysin, homologous to vasopressin-associated neurophysins, is reported. The protein contains a Tyr for Asn substitution at position 75, a position in direct contact with residues 77 and 78 of the monomer-monomer interface. This Tyr residue therefore serves as a potential reporter of the path involved in the long-range linkage between peptide binding and dimerization in this system. NMR studies of the protein in unliganded and liganded states demonstrated normal dimerization properties and the expected increase in dimerization associated with binding peptide. In keeping with an elevated pKa of 11.1 assigned to Tyr-75 by UV spectrophotometric titration, the NMR signals from the 3,5 and 2,6 ring protons of Tyr-75 were shifted 0.3 and 0.2 ppm upfield, respectively, relative to their positions in small peptides, indicating significant shielding and/or hydrogen bonding. The Tyr-75 ring proton signals narrowed slightly, with no discernible change in chemical shift, on conversion from dimer to monomer in the unliganded state. Ring protons of Tyr-49, distant from the monomer-monomer interface, but adjacent to the peptide-binding site, were markedly perturbed by dimerization, in accord with their behavior in bovine neurophysins. The results suggest that the secondary and tertiary structure of the region 75-78 is largely unchanged by dimerization, and argue against an important role for this region in dimerization-mediated conformational changes that alter the binding site in the unliganded state.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- H B Huang
- Department of Biochemistry, Cornell University Medical College, New York, NY
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Rholam M, Nicolas P, Cohen P. Binding of neurohypophyseal peptides to neurophysin dimer promotes formation of compact and spherical complexes. Biochemistry 1982; 21:4968-73. [PMID: 7138841 DOI: 10.1021/bi00263a021] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Previous hydrodynamic studies [Rholam, M., & Nicolas, P. (1981) Biochemistry 20, 5837-5843] have demonstrated that the dimerization of a neurophysin monomer (prolate ellipsoid with an axial ratio, due to asymmetry, of 5.2) results in a decreased asymmetry (axial ratio, due to asymmetry, of 3.6) as the consequence of a side-by-side association process. By a combination of hydrodynamic measurements, including the use of sedimentation velocity, viscometry, and fluorescence polarization spectroscopy, the influence of hormone binding on the shape and asymmetry properties of the neurophysin dimer was evaluated. The binding of ocytocin, vasopressin, and the tripeptide analogue of the N-terminal sequence of ocytocin, Cys(S-Me)-Tyr-Ile-NH2, results in an increase of S020,W and a decrease in both the reduced viscosity and rotational relaxation time of the bis-liganded dimeric species vs. the nonliganded form. The axial ratio (a/b) due to asymmetry of the ligand-bound dimers was found in each case to be equal to, or slightly greater than, 1.0, indicating a compact spherical shape (Stokes radius 21 A). The profound alteration on molecular dimensions observed upon ligand binding is shown to be the consequence of a ligand-induced conformational change and might explain the intradimeric binding sites positive cooperativity. It is tentatively proposed that the pseudospherical shape of the neurophysin-hormone complexes may enhance the stability of neurophysin and contribute to the prevention of leakage of neuropeptides through the membrane of neurosecretory granules. The data provide a remarkable example of a small protein with a high content in disulfide links and that undergoes conspicuous changes in conformation under the influence of nonapeptide, or tripeptide, ligands.
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Abercrombie DM, McCormick WM, Chaiken IM. Photoaffinity labeling of the hormone binding site of neurophysin. J Biol Chem 1982. [DOI: 10.1016/s0021-9258(18)34917-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Lord ST, Breslow E. Synthesis of peptide spin-labels that bind to neurophysin and their application to distance measurements within neurophysin complexes. Biochemistry 1980; 19:5593-602. [PMID: 7459333 DOI: 10.1021/bi00565a021] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The synthesis of two spin-labels capable of binding to the hormone-binding site(s) of neurophysin is described. The two spin-labels are 4-(glycyl-L-phenylalanylamido)-2,2,6,6-tetramethylpiperidinyl-1-oxy and S-[[[3-(2,2,5,5-tetramethylpyrrolidine-1-oxy)amino]carbonyl]methyl]-L-cysteinyl -L-tyrosine amide; synthesis of the former is achieved by a novel route to circumvent problems associated with nitroxide instability under standard conditions of peptide deblocking. NMR studies of the effects of binding these spin-labels on relaxation rates of individual proton resonances of neurophysin were used to calculate correlation times and distances between the bound nitroxides and the observed protons. The results indicate that residue 3 of peptides bound to the strong site of neurophysin is greater than or equal to 14 A from Tyr-49 and argue against a distance of < 5 A between the ortho ring protons of Tyr-49 and those of residue 2 of peptides bound to the strong site. Alternatively, the data suggest that the previously observed nuclear Overhauser effect between these protons reflects spin diffusion at the strong site and a contribution of uncertain magnitude from a second but very weak binding site; this second site is close to Tyr-49 and is detected by the increased relaxation rate of Tyr-49 ring protons when 4-(glycyl-L-phenylalanylamido)-2,2,6,6-tetramethylpiperidinyl-1-oxy is displaced from the strong site by competing diamagnetic peptide. Additionally, the data indicate that residue 3 of bound peptides at the strong site is distant from His-80 but approximately 12 A from the amino terminus. The extended side chain of residue 1 of peptides at the strong site is calculated as less than or equal to 10 A from Tyr-49.
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Bothner-By AA, Lemarie B, Walter R, Tiao-Te Co R, Rabbani LD, Breslow E. N.M.R. and equilibrium dialysis studies of the interaction of bovine neurophysin-1 with vasopressin and small peptides. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1980; 16:450-63. [PMID: 7216620 DOI: 10.1111/j.1399-3011.1980.tb02969.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The binding to bovine neurophysin of lysine-vasopressin and of lysine-vasopressin selectively deuterated at the protons ortho to the tyrosine hydroxyl was studied by proton n.m.r. and equilibrium dialysis. The principal object of these studies was to investigate reports that, at standard salt concentrations, neurophysin contained a second site specific for vasopressin. At pH 6, the effects of neurophysin-I on the line-width, longitudinal relaxation rate and nuclear Overhauser properties of the lysine-vasopressin tyrosine ring protons were interpretable in terms of a slow-exchange 1:1 interaction between lysine-vasopressin and neurophysin. Additionally, n.m.r. competition studies between lysine-vasopressin and L-phenylalanyl-L tyrosinamide suggested 1:1 competition for a single binding site on neurophysin. No evidence pointing to a significant second lysine-vasopressin-binding site was obtained from the n.m.r. studies. The lack of a moderately strong second binding site for lysine-vasopressin at neutral pH was also indicated by equilibrium dialysis studies at relatively high free hormone concentrations. These studies demonstrated only a single thermodynamically significant site for either oxytocin or vasopressin and failed to confirm a reported effect of LiCl on the number of sites available to oxytocin. It is suggested that secondary sites for the hormones are probably markedly weaker and less specific than reported elsewhere.
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Kawano K, Kobayashi Y, Kyogoku Y, Morikawa T, Sakakibara S. Conformational studies of oxytocin analogues with different ring sizes. I. Circular dichroism. BIOCHIMICA ET BIOPHYSICA ACTA 1979; 578:87-95. [PMID: 36924 DOI: 10.1016/0005-2795(79)90116-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Circular dichroic spectra were measured for three analogues of deamino-oxytocin of different ring sizes where the disulfide group of oxytocin is replaced by the (CH2)n group. Their backbone rings are composed of different numbers of atoms, i.e., they are nineteen, twenty and twenty-one for [1,6-aminopimelic acid]oxytocin (n = 1), [1,6-aminosuberic acid]oxytocin (n = 2) and [1,6-aminoazelaic acid]oxytocin (n = 3), respectively. The pH dependence of the circular dichroism spectra indicates that the conformation of [1,6-aminoazelaic acid]oxytocin is different from those of others and the temperature dependency reveals that the conformation of [1,6-aminopimelic acid]oxytocin is most rigid. [1,6-Aminosuberic acid]oxytocin is biologically most active among three derivatives and their biological activities are related to the conformation and internal motions of the peptide hormone analogues.
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Cohen P, Nicolas P, Camier M. Biochemical aspects of neurosecretion: neurophysin--neurohypophyseal hormone complexes. CURRENT TOPICS IN CELLULAR REGULATION 1979; 15:263-318. [PMID: 527370 DOI: 10.1016/b978-0-12-152815-7.50011-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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13
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Nicolas P, Wolff J, Camier M, Di Bello C, Cohen P. Importance of neurophysin dimer and of tyrosine-49 in the binding of neurohypophyseal peptides. J Biol Chem 1978. [DOI: 10.1016/s0021-9258(17)40868-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Nicolas P, Camier M, Dessen P, Cohen P. Interactions of oxytocin and vasopressin with bovine neurophysins I and II. Effects of hormone binding on the protein quaternary structure: a simple model. J Biol Chem 1976. [DOI: 10.1016/s0021-9258(17)33342-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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15
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Yazawa M, Noda LH. Studies on tyrosine residues in porcine muscle adenylate kinase. Circular dichroism spectra and chemical modification with tetranitromethane. J Biol Chem 1976. [DOI: 10.1016/s0021-9258(17)33493-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Blumenstein M, Hruby VJ. Carbon-13 nuclear magnetic resonance studies of the interaction of specifically labeled (90%-13C) oxytocin and arginine vasopressin with neurophysins. Biochem Biophys Res Commun 1976; 68:1052-8. [PMID: 1267763 DOI: 10.1016/0006-291x(76)90302-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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Interactions of bovine neurophysins with neurohypophyseal hormones. On the role of tyrosine-49. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)41298-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Abstract
The active sites of enzymes can be studied in great detail using nuclear magnetic resonance spectroscopy. The determination of pKa values of active site histidine residues in bovine pancreatic ribonuclease and the characterization of the binding of peptide hormones to carrier proteins are two such examples. The study of the active site of staphylococcal nuclease is another example and is presented in detail in this paper. The structure of 3'5'-thymidine diphosphate bound in the active site of staphylococcal nuclease has been studied by measuring the relaxation rate enhancement of substrate analog nuclei by a paramagnetic metal ion. The lanthanide ion, Gd(III), was substituted for Ca(II) in the formation of the ternary complex of nuclease: Gd(III) : 3'5'-thymidine diphosphate. Measurements were made of the transverse relaxation rates of protons and the longitudinal and transverse relaxation rates of the phosphorus nuclei of bound nucleotide. Internuclear distances between the metal ion and atoms of the 3'5'-thymidine diphosphate nucleotide were determined from these data by using the Solomon-Bloembergen equation. In general, these distances corresponded closely to those determined by previous X-ray crystallography of the thymidine diphosphate complex. These internuclear distances were also used with a computer program and graphics display to solve for metal : nucleotide geometries which were consistent with the experimental data. A geometry similar to the structure of the metal : nucleotide complex bound to nuclease determined by X-ray analysis was one of the solutions to this computer modeling process. For staphylococcal nuclease the NMR and X-ray methods yield compatible high resolution information about the structure of the active site.
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Cohen P, Camier M, Wolff J, Alazard R, Cohen JS, Griffin JH. Studies of bovine neurophysin-neurohypophyseal hormone interactions. Ann N Y Acad Sci 1975; 248:463-79. [PMID: 235235 DOI: 10.1111/j.1749-6632.1975.tb34207.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Breslow E. On the mechanism of binding of neurohypophyseal hormones and analogs to neurophysins. Ann N Y Acad Sci 1975; 248:423-41. [PMID: 1054557 DOI: 10.1111/j.1749-6632.1975.tb34203.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Di Bello C, Griffin JH. Circular dichroism and absorbance properties of nitrotyrosyl chromophores in staphylococcal nuclease and in a model diketopiperazine. J Biol Chem 1975. [DOI: 10.1016/s0021-9258(19)41833-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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23
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Alazard R, Cohen P, Cohen JS, Griffin JH. Interactions of Bovine Neurophysin II with Oxytocin and [8-Lysine] Vasopressin. J Biol Chem 1974. [DOI: 10.1016/s0021-9258(19)42142-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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