101
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Fernandes BM, Kohn A, Pinto RM. Aspidogastrid and digenetic trematode parasites of marine fishes of the coast of Rio de Janeiro State, Brazil. REVISTA BRASILEIRA DE BIOLOGIA 1985; 45:109-16. [PMID: 4059605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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102
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Kohn A. [New developments in Rotavirus research]. HAREFUAH 1984; 107:208-10. [PMID: 6097517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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103
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Kühnreich E, Naschitz JE, Kohn A, Yeshurun D. [Familial Mediterranean fever presenting with recurrent severe myalgia]. HAREFUAH 1984; 106:209-10. [PMID: 6724410] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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104
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Kohn A, Macedo B. First record of Aspiculuris tetraptera (Nitzsch, 1821) (Nematoda : Oxyuroidea) and Dollfusentis chandleri (Golvan, 1969) (Acanthocephala : Illiosentidae) in Haemulon sciurus (Shaw 1803) (Pisces : Pomadasyidae). ANNALES DE PARASITOLOGIE HUMAINE ET COMPAREE 1984; 59:477-82. [PMID: 6508143 DOI: 10.1051/parasite/1984595477] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Forty specimens of Haemulon sciurus were examined for endoparasites and this paper refers to the recovered Nematodes and Acanthocephalans. Aspiculuris tetraptera is for the first time referred in fish and Dollfusentis chandleri is recorded in Brazil and in a new host.
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105
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Abstract
This chapter discusses the newer modifications of immunosorbent electron microscopy (ISEM) methods in both plant and animal virology. ISEM methods presented in the chapter include all the techniques where the “solid phase principle” is essential in a way similar to other solid phase immunoassays. These methods include (1) the antibody-coated grid technique (AB-CGT); (2) the protein A-coated grid technique (PA-CGT); (3) the protein A-coated bacteria technique (PA-CBT); and (4) the antigen-coated grid technique (AG-CGT). In all ISEM methods, one of the components of the system is adsorbed to a solid phase. In AG-CGT, PA-CGT, and AB-CGT, one of the reagents is adsorbed to an electron microscopic grid, while in PA-CBT protein A is naturally present on the surface of a bacterium that serves as a solid support. In ISEM methods, the viruses can be statistically evaluated and numerically expressed as number of virions per unit of area, and can, therefore, be statistically evaluated. Thus, these methods optimize the results of a test by quantifying the effects of the quality of the supporting grid, the time of adsorption, the pH, the presence of salts, and the type of staining. The ISEM also permits a detailed study of antigenic variations in the same genus of virus, and thus would visually pinpoint the type or strain differences.
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106
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Fernandes BM, Kohn A. Lintonium vibex (Linton, 1900) (Trematoda, Fellodistomidae) parasitizing Stephanolepis hispidus (Pisces, Balistidae). ANNALS OF TROPICAL MEDICINE AND PARASITOLOGY 1983; 77:539-40. [PMID: 6660960 DOI: 10.1080/00034983.1983.11811749] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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107
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Delle Fave G, Kohn A, De Magistris L, Annibale B, Bruzzone R, Sparvoli C, Severi C, Torsoli A. Effects of bombesin on gastrin and gastric acid secretion in patients with duodenal ulcer. Gut 1983; 24:231-5. [PMID: 6826108 PMCID: PMC1419938 DOI: 10.1136/gut.24.3.231] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The effect of bombesin, a possible neurotransmitter of gastrin release, upon gastrin and gastric acid secretion was investigated in 25 patients with duodenal ulcer and in 16 normal subjects. In patients with duodenal ulcer bombesin (10 ng/kg/min) produced an increase in plasma gastrin output (median 22.4 (range 7.5-75.8) pmol/l/min) similar to that obtained in normal subjects (median 24.4 (range 5.8-56.5) pmol/l/min), whereas gastrin stimulated by a meal was significantly higher in the group of patients with duodenal ulcer (median 20.7 (range 9.2-42.9) vs 16.2 (range 3.4-22.2) p<0.05). Peak acid output induced by bombesin was significantly higher in patients with duodenal ulcer than in normal subjects (median 24.4 (range 9.0-63.8) vs 14.0 (range 3.0-24.8) mmol/h, p<0.05) despite identical gastrin outputs. The ratio (%) obtained by dividing the acid secretory response to bombesin by the response to pentagastrin, however, was similar in both normal subjects and patients with duodenal ulcer (median 55 (range 20-116) vs 58 (range 31-95) respectively). The difference between the gastrin response to food and bombesin could be explained by the fact that bombesin releases gastrin directly, whereas a protein meal involves several mechanisms (neural, peptidergic, paracrine, endocrine), either stimulatory or inhibitory. The above results indicate that a higher concentration in antral and/or duodenal gastrin is unlikely to be present in patients with duodenal ulcer. An increased parietal cell mass could explain the higher gastric acid response after bombesin infusion in our group of patients with duodenal ulcer.
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108
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Kohn A. [Does influenza virus pave the way for bacteria?]. HAREFUAH 1983; 104:155-6. [PMID: 6654230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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109
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Fuchs P, Kohn A. Changes induced in cell membranes adsorbing animal viruses, bacteriophages, and colicins. Curr Top Microbiol Immunol 1983; 102:57-99. [PMID: 6301761 DOI: 10.1007/978-3-642-68906-2_2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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110
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Pinto RM, Kohn A, Fernandes BMM, Mello DA. Nematodes of rodents in Brazil, with description of Aspidodera vicentei n.sp. Syst Parasitol 1982. [DOI: 10.1007/bf00009627] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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111
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Corazziari E, Delle Fave G, Pozzessere C, Kohn A, de Magistris L, Anzini F, Torsoli A. Effect of bombesin on lower esophageal sphincter pressure in humans. Gastroenterology 1982; 83:10-4. [PMID: 7075935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
Intravenous infusion of bombesin in humans results in increased serum gastrin levels and increased lower esophageal sphincter pressure. To differentiate a gastrin- from a nongastrin-mediated mechanism, the effect of intravenous bombesin infusion on lower esophageal sphincter pressure was studied in 5 healthy subjects and in 5 antrectomized patients. Lower esophageal sphincter pressure was recorded by three continuously perfused catheters with side-openings located 5 mm apart. Blood samples were taken at regular intervals during the study periods to assay gastrin and pancreatic polypeptide. Manometric tracings and blood samples were coded and evaluated blindly. Lower esophageal sphincter pressure increased during bombesin infusion both in normal and antrectomized subjects. The increase had a delayed onset and persisted after discontinuation of bombesin. No correlation was found between lower esophageal sphincter pressure and serum gastrin or pancreatic polypeptide values. These data indicate that the effect of bombesin on lower esophageal sphincter pressure is not gastrin or pancreatic polypeptide mediated.
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112
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Kohn A, Macedo B, Fernandes BMM. About some trematodes parasites of Haemulon sciurus (Shaw, 1803). Mem Inst Oswaldo Cruz 1982. [DOI: 10.1590/s0074-02761982000200004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
From September, 1980 to August, 1981 forty specimens of Haemulon sciurus from "Praia da Ribeira, Ilha do Governador", Rio de Janeiro State, were examined for parasites. In this paper, parcial results concerning only the collected trematodes are reported: Diplomonorchis leiostomi Hopkins, 1941 (first record in Brazil and in a new host); Lasiotocus beauforti (Hopkins, 1941) Thomas, 1959 (new host record); Genolopa ampullacea Linton, 1910; Parahemiurus merus (Linton, 1910) Yamaguti, 1938 (new host record): Aponurus pyriformis (Linton, 1910) Overstreet, 1973 and Diplangus paxillus Linton, 1910. Figures, measurements and comments of each species are given.
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113
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Kohn A. [Toward a rotavirus vaccine]. HAREFUAH 1982; 102:349-50. [PMID: 6288530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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114
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Kohn A, Theves G. [Bovine leukosis]. BULLETIN DE LA SOCIETE DES SCIENCES MEDICALES DU GRAND-DUCHE DE LUXEMBOURG 1982; 119:45-49. [PMID: 7116549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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115
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Kohn A, López-Alvarez ML, Katz N. Transmission and scanning electron microscopical studies in the tegument of male Schistosoma mansoni after oxamniquine treatment. ANNALES DE PARASITOLOGIE HUMAINE ET COMPAREE 1982; 57:285-91. [PMID: 7137803 DOI: 10.1051/parasite/1982573285] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Schistosoma mansoni recovered from experimentally infected mice orally treated with oxamniquine were studied by transmission and scanning electron microscopy. The worms were examined 24 hours, 3, 7 and 10 days after a single dose of 100 mg/Kg of the drug. After oxamniquine treatment significant structural alterations were observed in tegumental, muscular and parenchymal levels. The initial alterations were confined to basal vacuolation in the tegument and to structural disorganization both in tegumental and non tegumental cells. Ten days after treatment, intercellular oedema became more prominent originating "bubble-like" lesions with varied dimensions. The intercellular oedema leading to the "bubble" formation seems to be the most striking feature caused by oxamniquine treatment.
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116
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Kohn A, Fernandes BM. Neoapocreadium chabaudi sp. n. (Apocreadiidae) and Schikhobalotrema acuta (Linton, 1910) (Haplosplanchnidae) trematodes parasites of marine fishes in Brazil. ANNALES DE PARASITOLOGIE HUMAINE ET COMPAREE 1982; 57:121-6. [PMID: 7125492 DOI: 10.1051/parasite/1982572121] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Neoapocreadium chabaudi sp. n. (Digenea, Apocreadiidae) is described from the intestine of a marine fish Stephanolepis hispidus from Brazil, and the genus Schikhobalotrema Skrjabin & Guschanskaja, 1955 represented by its type species S. acuta (Linton, 1910) Skrjabin and Guschanskaja, 1955, is for the first time reported from the intestine of Strongylura marina in Brazil. N. chabaudi sp. n. is more closely related to N. angustum (Sogandares-Bernal, 1959) from which differs mainly in the size of the eggs, by the presence of intercecal vitelline follicles in the region between the testes and acetabulum, and by the large genital atrium.
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117
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Kohn A, Fernandes BM, Pinto RM, Mello DA. Maritremopsis mariettavogeae sp. n. (Trematoda, Microphallidae) and Amphimerus lancea (Diesing, 1850) (Trematoda, Opisthorchiidae) parasites of Nectomys squamipes (Rodentia) in Brazil. Mem Inst Oswaldo Cruz 1981; 76:393-6. [PMID: 6757646 DOI: 10.1590/s0074-02761981000400007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
In this paper two species of trematodes recovered from nectomys squamipes from Goiás State, Brazil, are presented. Maritremopsis mariettavogeae sp. n. is compared to M. proxilum (Caballero & Montero-Gei, 1961) and M. belopolskaiae (Caballero, 1964). Amphimerus lancea originally described from a cetacean host, is for the first time referred in a rodent.
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118
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de Magistris L, Delle Fave G, Kohn A, Schwartz TW. Differential stimulation of pancreatic-polypeptide and gastrin secretion by bombesin in man. Life Sci 1981; 28:2617-21. [PMID: 7266241 DOI: 10.1016/0024-3205(81)90719-0] [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: 01/24/2023]
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119
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Kohn A, Gitelman J, Inbar M. Interaction of polyunsaturated fatty acids with animal cells and enveloped viruses. Antimicrob Agents Chemother 1980; 18:962-8. [PMID: 7235682 PMCID: PMC352998 DOI: 10.1128/aac.18.6.962] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Essential unsaturated fatty acids such as oleic, linoleic, or arachidonic were incorporated into the phospholipids of animal cells and induced in them a change in the fluidity of their membranes. Exposure of enveloped viruses such as arbo-, myxo-, paramyxo-, or herpesviruses to micromolar concentrations of these fatty acids (which are not toxic to animal cells) caused rapid loss of infectivity of these viruses. Naked viruses such as encephalomyocarditis virus, polio virus or simian virus 40 were not affected by incubation with linoleic acid. The loss of infectivity was attributed to a disruption of the lipoprotein envelope of these virions, as observed in an electron microscope.
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120
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Kohn A, Gitelman J, Inbar M. Unsaturated free fatty acids inactivate animal enveloped viruses. Arch Virol 1980; 66:301-7. [PMID: 7447706 DOI: 10.1007/bf01320626] [Citation(s) in RCA: 74] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Unsaturated free fatty acids such as oleic, arachidonic or linoleic at concentrations of 5-25 microgram/ml inactivate enveloped viruses such as herpes, influenza, Sendai, Sindbis within minutes of contact. At these concentrations the fatty acids are inocuous to animal host cells in vitro. Naked viruses, such as polio, SV40 or EMC are not affected by these acids. Saturated stearic acid does not inactivate any viruses at concentrations tested. Though the mode of action of unsaturated fatty acids is not understood, electronmicrographs of enveloped viruses treated by them indicate that the inactivation is associated with disintegration of the virus envelope.
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121
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Katz D, Straussman Y, Shahar A, Kohn A. Solid-phase immune electron microscopy (SPIEM) for rapid viral diagnosis. J Immunol Methods 1980; 38:171-4. [PMID: 7452001 DOI: 10.1016/0022-1759(80)90341-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Immune electron microscopy (IEM) is one of the fastest and most sensitive methods for the detection and diagnosis of viruses. This technique is based on formation of immune complexes of the virus with its corresponding antibody. In IEM optimal precipitation depends on a correct ratio, and there is a prozone effect. These problems can be overcome by using the solid-phase immune electron microscopic (SPIEM) technique. In this technique the antibody is attached to a particle which is used for 'fishing' the virus to be examined out of the suspension. After low speed centrifugation the preparation is treated either for observation in the transmission electron microscope or in the scanning electron microscope. In 'positive' samples the virus is seen attached to the surface of the particle. We report here results with S. aureus as the solid phase for the detection of Sindbis virus. The anti-Sindbis gamma globulins are attached to the bacteria by means of protein A present on their surface.
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122
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Delle Fave G, Kohn A, de Magistris L, Mancuso M, Sparvoli C. Effect of bombesin-stimulated gastrin on gastric acid secretion in man. Life Sci 1980; 27:993-9. [PMID: 7432100 DOI: 10.1016/0024-3205(80)90110-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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123
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Fuchs P, Gruber E, Gitelman J, Kohn A. Nature of permeability changes in membrane of HeLa cells adsorbing Sendai virus. J Cell Physiol 1980; 103:271-8. [PMID: 6254995 DOI: 10.1002/jcp.1041030212] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Adsorption of Sendai virus to HeLa cells induced in them an increased permeability to K+, Na+, Ca++, deoxyglucose, but not to fluorescein. The stimulation of uptake of 42K was temperature-dependent, did not occur below 15 degrees C, and was not inhibited by ouabain. The virus-induced increase in the uptake and release of 42K and of 3H deoxyglucose could not be mimicked by treatment of cells with linoleic acid, a procedure which increased the fluidity of the cellular membranes. The stimulatory effect of 0.5 mM ATP on the release of deoxyglucose was enhanced several fold in the presence of Sendai virus. These results seem to indicate the possible involvement of membranal enzymes such as e.g. protein kinase in the permeability changes induced by Sendai virus.
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124
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DelleFave G, Tamburrano G, de Magistris L, Mauceri M, Kohn A, BouFayad J. Glucagon-like immunoreactivity (GLI) induced by bombesin (BBS) in man. ACTA ACUST UNITED AC 1980. [DOI: 10.1016/0167-0115(80)90068-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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125
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Wilcox KW, Kohn A, Sklyanskaya E, Roizman B. Herpes simplex virus phosphoproteins. I. Phosphate cycles on and off some viral polypeptides and can alter their affinity for DNA. J Virol 1980; 33:167-82. [PMID: 6245226 PMCID: PMC288534 DOI: 10.1128/jvi.33.1.167-182.1980] [Citation(s) in RCA: 205] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
We report on phosphorylation, the stability of the bound phosphate, and the properties of several phosphorylated infected-cell polypeptides (ICPs) synthesized in cells infected with herpes simplex virus 1 and 2. Our results and conclusions are as follows. (i) Phosphorylation of ICPs occurs by at least two different pathways. Thus, the 4a and 4c electrophoretic forms of ICP 4 were labeled with 32P during a pulse concurrently with their synthesis, whereas ICP 22 and ICP 27 were labeled with 32P only during a subsequent chase in the presence of unlabeled phosphate. (ii) Pulse chase studies with [35S]methionine and 32P indicate that whereas most polypeptides are stable, the bound phosphate with few exceptions cycles on and off. Of special interest is the observation that the phosphate bound to ICP 4a and 4c cycles on and off, whereas that bound to ICP 4b is stably associated. Similar cycling was observed for ICP 6, 11, 22, and 27. The observation that 4a and 4c can be phosphorylated as late as 24 h after infection, i.e., long after their synthesis ceases, suggests that all three forms may have defined functions that persist throughout the reproductive cycle. (iii) All three forms of ICP 4 can be the translational products of only one of two copies of the ICP 4 gene in the viral genome. (iv) Analyses of the distribution of the viral proteins within the cell indicate that phosphorylation is not a major determinant in the compartmentalization of most viral phosphoproteins. (v) Comparisons of the binding to DNA-cellulose of artificial mixtures of 32P- and [35S]methionine-labeled proteins from infected cells indicate that phosphorylation in some instances enhances (e.g., ICP 29) and in other instances decreases (e.g., ICP 6) binding affinity for DNA. In light of previous reports that some of the proteins identified as phosphoproteins have regulatory functions, the data suggest that phosphorylation may modify the activity of regulatory proteins in herpes simplex virus-infected cells.
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