1
|
|
2
|
Pouckova P, Skvor J, Gotte G, Vottariello F, Slavik JT, Matousek J, Laurents DV, Libonati M, Soucek J. Some biological actions of PEG-conjugated RNase A oligomers. Neoplasma 2006; 53:79-85. [PMID: 16416018] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Previously we have shown that monomeric RNase A has no significant biological activity, whereas its oligomers (dimer to tetramer) prepared by lyophilizing from 50% acetic acid solutions, show remarkable aspermatogenic and antitumor activities. Furthermore, conjugates prepared by chemical binding of native RNase A to polyethylene glycol (PEG) have shown a significant aspermatogenic and antitumor activities. In this work we show that the chemical conjugation of PEG to the RNase A C-dimer, and to the two RNase A trimers (NC-trimer and C- trimer) decreases the aspermatogenic activity of the oligomers while increasing their inhibitory activity on the growth of the human UB900518 amelanotic melanoma transplanted in athymic nude mice. Moreover, the PEG-conjugated RNaseA oligomers are devoid, like the free oligomers, of any embryotoxic activity.
Collapse
Affiliation(s)
- P Pouckova
- Institute of Hematology and Blood Transfusion, 12820 Prague, Czech Republic
| | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Affiliation(s)
- M Libonati
- Dipartimento di Scienze Neurologiche e della Visione, Sezione di Chimica Biologica, Facoltà di Medicina e Chirurgia, Università di Verona, Strada Le Grazie 8, 37134, Verona, Italy.
| |
Collapse
|
4
|
Affiliation(s)
- M Libonati
- Dipartimento di Scienze Neurologiche e della Visione, Sezione di Chimica Biologica, Università di Verona, Verona 37134, Italy
| | | |
Collapse
|
5
|
Abstract
Ribonuclease A aggregates (dimers, trimers, tetramers, pentamers) can be obtained by lyophilization from 40% acetic acid solutions. Each aggregate forms two conformational isomers distinguishable by different basic net charge. The crystal structure of the two dimers has recently been determined; the structure of the higher oligomers is unknown. The results of the study of the two trimeric and tetrameric conformers can be summarized as follows: (1) RNase A trimers and tetramers form by a 3D domain-swapping mechanism. N-terminal and C-terminal types of domain swapping could coexist; (2) the secondary structures of the trimeric and tetrameric conformers do not show significant differences if compared with the secondary structure of monomeric RNase A or its two dimers; (3) a different exposure of tyrosine residues indicates that in the aggregates they have different microenvironments; (4) the two trimeric and tetrameric conformers show different susceptibility to digestion by subtilisin; (5) dimers, trimers, and tetramers of RNase A show unwinding activity on double-helical poly(dA-dT) x poly(dA-dT), that increases as a function of the size of the oligomers; (6) the less basic conformers are more stable than the more basic ones, and a low concentration in solution of trimers and tetramers favors their stability, which is definitely increased by the interaction of the aggregates with poly(dA-dT) x poly(dA-dT); (7) the products of thermal dissociation of the two trimers indicate that their structures could be remarkably different. The dissociation products of the two tetramers allow the proposal of two models for their putative structures.
Collapse
Affiliation(s)
- A Nenci
- Dipartimento di Scienze Neurologiche e della Visione, Sezione di Chimica Biologica, Università di Verona, Verona, Italy
| | | | | | | |
Collapse
|
6
|
Abstract
Bovine pancreatic ribonuclease (RNase A) forms two types of dimers (a major and a minor component) upon concentration in mild acid. These two dimers exhibit different biophysical and biochemical properties. Earlier we reported that the minor dimer forms by swapping its N-terminal alpha-helix with that of an identical molecule. Here we find that the major dimer forms by swapping its C-terminal beta-strand, thus revealing the first example of three-dimensional (3D) domain swapping taking place in different parts of the same protein. This feature permits RNase A to form tightly bonded higher oligomers. The hinge loop of the major dimer, connecting the swapped beta-strand to the protein core, resembles a short segment of the polar zipper proposed by Perutz and suggests a model for aggregate formation by 3D domain swapping with a polar zipper.
Collapse
Affiliation(s)
- Y Liu
- UCLA-DOE Laboratory of Structural Biology and Molecular Medicine, Department of Chemistry and Biochemistry and Biological Chemistry, University of California, Los Angeles, California 90095-1570, USA
| | | | | | | |
Collapse
|
7
|
Nenci A, Gotte G, Maras B, Libonati M. Different susceptibility of the two dimers of ribonuclease A to subtilisin. Implications for their structure. Biochim Biophys Acta 2001; 1545:255-62. [PMID: 11342051 DOI: 10.1016/s0167-4838(00)00287-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
RNase A and its minor and major dimers were digested with subtilisin under controlled conditions. The major dimer was found to be slightly more resistant, the minor dimer markedly less resistant to subtilisin than monomeric RNase A. Two S-proteins formed for each RNase A species, one starting with Ser-21, the other with Ser-22. Their relative proportions indicate that the structure of the minor dimer, whose identity with that of a RNase A dimer shown to be 3D domain-swapped is strongly suggested by recent work [S. Sorrentino et al. (2000) FEBS Lett. 466, 35-39], makes its peptide bond between Ser-21 and Ser-22 more accessible to subtilisin than it is in RNase A and its major dimer. Moreover, (i) both subunits constituting the minor dimer are more susceptible to subtilisin than monomeric RNase A, and (ii) the susceptible bonds in one of its two exchanging N-terminal arms are more accessible to the protease than in the other. The properties of the major dimer suggest that its structure could be different.
Collapse
Affiliation(s)
- A Nenci
- Dipartimento di Scienze Neurologiche e della Visione, Facoltà di Medicina, Università di Verona, Italy
| | | | | | | |
Collapse
|
8
|
Abstract
In 1965 Fruchter and Crestfield (J. Biol. Chem. 240, 2868-3874) observed that dimeric RNase A prepared by lyophilization from acetic acid could be separated into two forms. Surprisingly, no other structural or functional differences could be detected between the two forms. In 1998 a structure for dimeric RNase A was determined by X-ray crystallography by Liu et al. (Proc. Natl. Acad. Sci. USA 95, 3437-3442). We found that the two forms of dimeric RNase A have indeed different structural and functional properties, and suggest that the dimer whose structure was investigated by Liu and coworkers may be identified with the lesser form of dimeric RNase A.
Collapse
Affiliation(s)
- S Sorrentino
- Dipartimento di Chimica Organica e Biologica, Università di Napoli Federico II, Via Mezzocannone 16, 80134, Naples, Italy
| | | | | | | | | | | | | |
Collapse
|
9
|
Gotte G, Bertoldi M, Libonati M. Structural versatility of bovine ribonuclease A. Distinct conformers of trimeric and tetrameric aggregates of the enzyme. Eur J Biochem 1999; 265:680-7. [PMID: 10504400 DOI: 10.1046/j.1432-1327.1999.00761.x] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Lyophilization of bovine ribonuclease A (RNase A; Sigma, type XII-A) from 40% acetic acid solutions leads to the formation of approximately 14 aggregated species that can be separated by ion-exchange chromatography. Several aggregates were identified, including two variously deamidated dimeric subspecies, two distinct trimeric and two distinct tetrameric RNase A conformers, besides the two forms of dimer characterized previously [Gotte, G. & Libonati, M. (1998) Two different forms of aggregated dimers of ribonuclease A. Biochim. Biophys. Acta 1386, 106-112]. We also have possible evidence for the existence of two forms of pentameric RNase A. The two forms of trimers and tetramers are characterized by: (a) slightly different gel filtration patterns; (b) different retention times in ion-exchange chromatography; and (c) different mobilities in cathodic gel electrophoresis under nondenaturing conditions. Therefore, they appear to have distinct structural organizations responsible for a different availability of their positively charged amino acid residues. All RNase A oligomers, in particular the two distinct trimeric and tetrameric conformers, degrade poly(A).poly(U), viral double-stranded RNA and polyadenylate with a catalytic efficiency that is in general higher for the more basic species. On the contrary, the activity of the RNase A oligomers, from dimer to pentamer, on yeast RNA and poly(C) (Kunitz assay) is lower than that of monomeric RNase A.
Collapse
Affiliation(s)
- G Gotte
- Dipartimento di Scienze Neurologiche e della Visione, Sezione di Chimica Biologica, Facoltà di Medicina e Chirurgia, Università di Verona, Italy
| | | | | |
Collapse
|
10
|
Sorrentino S, D'Alessandro AM, Maras B, Di Ciccio L, D'Andrea G, De Prisco R, Bossa F, Libonati M, Oratore A. Purification of a 76-kDa iron-binding protein from human seminal plasma by affinity chromatography specific for ribonuclease: structural and functional identity with milk lactoferrin. Biochim Biophys Acta 1999; 1430:103-10. [PMID: 10082938 DOI: 10.1016/s0167-4838(98)00269-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
A pink-colored iron-binding protein has been found in large amount in human seminal plasma and identified as a lactoferrin isoform. Its purification, by a modification of a three-step chromatography procedure developed in an attempt to purify a ribonuclease from the same fluid, provided about 15-18 mg of pure protein from 100 ml of seminal plasma. Despite its ability to bind a ribonuclease ligand during the affinity step, the iron-binding protein did not display any detectable RNase activity in a standard assay with yeast RNA as substrate. It showed an apparent molecular weight of 76 kDa and resulted to be quite similar, if not identical, to human milk lactoferrin in many respects. Its N-terminal sequence (31 amino acid residues) starting with Arg-3 was identical to that of one of the N-terminally truncated lactoferrin variants isolated from human milk. Moreover, the amino acid sequence of a number of peptides, which represented about 23% of the entire sequence, has been also shown to be identical to that of the corresponding peptides of human milk lactoferrin. Double diffusion analysis revealed full recognition by antibodies anti-human milk lactoferrin of the human seminal plasma protein. Using immunoblotting analysis, both human milk lactoferrin and human seminal protein were recognized by antibodies anti-milk lactoferrin. When tested for its iron binding capacity, with Fe-NTA as iron donor, the protein purified was able to bind iron up to 100% saturation, as judged by absorbance at 465 nm.
Collapse
Affiliation(s)
- S Sorrentino
- Dipartimento di Chimica Organica e Biologica, Università di Napoli, via Mezzocannone 16, I-80136, Naples, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Cavallini G, Bovo P, Bianchini E, Carsana A, Costanzo C, Merola M, Sgarbi D, Frulloni L, Di Francesco V, Libonati M, Palmieri M. Lithostathine messenger RNA expression in different types of chronic pancreatitis. Mol Cell Biochem 1998; 185:147-52. [PMID: 9746220 DOI: 10.1023/a:1006843309128] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [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: 01/03/2023]
Abstract
Lithostathine may play a physiological role in preventing the precipitation of excess calcium in the pancreatic juice. The hypothesis has been advanced that in chronic calcifying pancreatitis the abnormal biosynthesis of lithostathine might be the original defect to which genetic proneness to the disease may be ascribed. The aim of the present work was to study lithostathine messenger RNA expression in the pancreas of patients with different types of pancreatitis. Lithostathine and chymotrypsinogen mRNA were determined in surgical specimens obtained from the pancreases of the following subjects: (a) 13 patients with chronic alcoholic pancreatitis (84.6% calcified); (b) 4 patients with chronic hereditary pancreatitis (all calcified); (c) 6 patients with chronic obstructive pancreatitis (4 calcified); and (d) 27 subjects suffering from pancreatic cancer. Significantly lower concentrations of both mRNAs were found in the pancreases of chronic pancreatitis patients than in non-cancerous tissue from pancreatic cancer subjects. However, about 70% of the pancreatic cancer subjects showed lithostathine and chymotrypsinogen mRNA levels comparable to those of chronic pancreatitis patients. These results indicate that the decrease in the level of mRNA is not specific to lithostathine and it is unrelated to the presence of pancreatic stones.
Collapse
Affiliation(s)
- G Cavallini
- Istituto di Clinica Medica, Cattedra di Gastroenterologia, Università degli Studi di Verona, Italy
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
12
|
Abstract
Results of gel filtration experiments performed with two different chromatographic media (Superose 12 HR 10/30 and Superdex 75 HR 10/30) and of polyacrylamide gel electrophoresis under non-denaturing and denaturing conditions suggest that aggregated dimers of bovine RNase A, obtained by lyophilization of the enzyme from 40% acetic acid solutions (5 mg RNase A per ml), might consist of two differently structured forms. These two species have slightly different retention times in gel-filtration experiments and migrate differently in electrophoresis under non-denaturing conditions. The fast migrating dimer in non-denaturing gel electrophoresis is able to degrade double-stranded poly(A).poly(U) more efficiently than the other, and the two forms are found in a ratio of about 3:1.
Collapse
Affiliation(s)
- G Gotte
- Dipartimento di Scienze Neurologiche e della Visione, Sezione di Chimica Biologica, Facoltà di Medicina e Chirurgia, Università di Verona, Strada Le Grazie 8, I-37134 Verona, Italy
| | | |
Collapse
|
13
|
Gotte G, Testolin L, Costanzo C, Sorrentino S, Armato U, Libonati M. Cross-linked trimers of bovine ribonuclease A: activity on double-stranded RNA and antitumor action. FEBS Lett 1997; 415:308-12. [PMID: 9357989 DOI: 10.1016/s0014-5793(97)01147-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.9] [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: 02/05/2023]
Abstract
Trimers of bovine pancreatic RNase A were obtained by cross-linking native RNase A with dimethyl suberimidate. They degrade double-stranded RNA more efficiently than dimers and monomers of RNase A, and display significant cytotoxic and/or cytostatic actions against C4-I cells (a human cell line derived from squamous carcinoma of the uterus cervix). On the same cell line cross-linked dimers of RNase A appear to be ineffective.
Collapse
Affiliation(s)
- G Gotte
- Institute of Biological Chemistry, Faculty of Medicine, The University of Verona, Italy
| | | | | | | | | | | |
Collapse
|
14
|
Yakovlev G, Moiseyev GP, Sorrentino S, De Prisco R, Libonati M. Single-strand-preferring RNases degrade double-stranded RNAs by destabilizing its secondary structure. J Biomol Struct Dyn 1997; 15:243-50. [PMID: 9399152 DOI: 10.1080/07391102.1997.10508189] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [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: 02/05/2023]
Abstract
To establish the mechanism of dsRNA degradation by mammalian single-stranded-preferring ribonucleases, and, in particular, the influence of their positively charged non-catalytic amino acid residues, we have studied the kinetic parameters of the depolimerization of single- and double-stranded polyribonucleotides such as poly(U), poly(U).poly(A), poly(C) and poly(C).poly(I) by the action of human seminal RNase, bovine seminal RNase and ox pancreas RNase A. While the activities of these RNases on poly(I).poly(C) were definitely lower than those on poly(C), the activities of human seminal and bovine seminal RNases on poly(U).poly(A) and poly(U) were of the same order of magnitude under physiological salt conditions. The ratio of the RNase A degrading activities towards poly(U) and poly(U).poly(A) at I = 0.16 M is ten times higher than the corresponding ratios determined with bovine seminal and human seminal ribonucleases. The high activities of these two RNases towards poly(U).poly(A) are discussed on the basis of their efficient estabilishing action on this double-helical nucleic acid due to their high affinity for poly(A). The destabilizing action of human seminal RNase and bovine seminal RNase on the poly (U).poly(A) duplex is higher than that measurable with bovine RNase A because of the higher number of positive charges present on those enzyme molecules. This may therefore explain why human seminal and bovine seminal ribonucleases are more efficient than RNase A in the depolymerization of poly(U).poly(A) at physiological ionic strength.
Collapse
Affiliation(s)
- G Yakovlev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow, Russia.
| | | | | | | | | |
Collapse
|
15
|
Abstract
Human extracellular ribonucleases (RNase), together with other members of the mammalian RNase superfamily, can be classified into four different enzyme types on the basis of their structural, catalytic and/or biological properties. Their occurrence and main distinctive features have been described, and catalytic differences (action on single- and double-stranded RNAs, dependence of enzyme activity on pH, ionic strength and cations, and hydrolysis of cyclic nucleotides) have been comparatively analyzed and discussed. In addition, some data considered here concerning human nonpancreatic-type RNases may support the suggestion [Chuchillo et al. (1993) FEBS Lett. 333, 207-210] that the enzyme 'ribonuclease', presently classified as 'hydrolase', should be reclassified as 'transferase'.
Collapse
Affiliation(s)
- S Sorrentino
- Dipartimento di Chimica Organica e Biologica, Universita di Napoli, Italy
| | | |
Collapse
|
16
|
Bankiewicz KS, Leff SE, Nagy D, Jungles S, Rokovich J, Spratt K, Cohen L, Libonati M, Snyder RO, Mandel RJ. Practical aspects of the development of ex vivo and in vivo gene therapy for Parkinson's disease. Exp Neurol 1997; 144:147-56. [PMID: 9126164 DOI: 10.1006/exnr.1996.6401] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [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: 02/04/2023]
Abstract
Current approaches to gene therapy of CNS disorders include grafting genetically modified autologous cells or introducing genetic material into cells in situ using a variety of viral or synthetic vectors to produce and deliver therapeutic substances to specific sites within the brain. Here we discuss issues related to the application of ex-vivo and in-vivo gene therapies as possible treatments for Parkinson's disease. Autologous monkey fibroblasts engineered ex-vivo to express tyrosine hydroxylase were grafted into MPTP-treated monkeys and found to express for up to 4 months. Adeno-associated (AAV) viral vectors expressing beta-galactosidase or tyrosine hydroxylase were introduced into monkey brains to determine the extent of infection and the types of cells infected by the vector at 21 days and 3 months. Gene expression was detected at both time points and was restricted to neurons in the striatum. These experiments demonstrate that two different approaches can be used to deliver proteins into the CNS. However, further technological advances are required to optimize gene delivery, regulation of gene expression, and testing in appropriate functional models before gene therapy can be considered for treating human disease.
Collapse
Affiliation(s)
- K S Bankiewicz
- Somatix Therapy Corporation, Alameda, California 94501, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Libonati M, Bertoldi M, Sorrentino S. The activity on double-stranded RNA of aggregates of ribonuclease A higher than dimers increases as a function of the size of the aggregates. Biochem J 1996; 318 ( Pt 1):287-90. [PMID: 8761484 PMCID: PMC1217620 DOI: 10.1042/bj3180287] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [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: 02/02/2023]
Abstract
Stable bovine RNase A aggregates larger than dimers (identified as trimers, tetramers, pentamers and hexamers) were obtained by lyophilization of RNase A from 40-50% acetic acid solutions. The RNase activity of these aggregates was compared with that of monomeric RNase A on single- and double-stranded polyribonucleotides. Their activity toward poly(U) and yeast RNA slightly decreases as a function of the size of the aggregates. In contrast, their action on poly(A).poly(U) as substrate progressively increases from a relative activity of 1 for the RNase monomer to 10 for the hexamer. These results are discussed in the light of an already advanced hypothesis about a possible mechanism of RNase attack on double-stranded RNA.
Collapse
Affiliation(s)
- M Libonati
- Istituto di Chimica Biologica, Facoltà di Medicine e Chirurgla, Università di Verona, Italy
| | | | | |
Collapse
|
18
|
Carra G, Giunta M, Benati C, Bovolenta C, Tridente G, Libonati M, Gerosa F. Selective association of a 22-38 kDa glycoprotein with MHC class II DP antigen on activated human lymphocytes at the plasma membrane. Mol Immunol 1996; 33:269-78. [PMID: 8649448 DOI: 10.1016/0161-5890(95)00143-3] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Two-dimensional electrophoretic analysis (2D-PAGE) of cell surface human DP and DR class II antigens identified a glycoprotein, designated pX, that is associated at the cell surface with DP but not DR class II antigen in activated T, B and NK lymphocytes but not in resting B lymphocytes, Raji B lymphoma cells, activated thymic epithelial cells or activated monocytes. pX is a heavily glycosylated protein with an apparent molecular mass spanning between 38 kDa and 22 kDa, that is reduced, after deglycosylation with Endo-F, to 22 kDa. The pX structure appears nonpolymorphic and independent of DP polymorphism, as suggested by 2D-PAGE migrational pattern of 125I-labelled Endo-F deglycosylated DP immunoprecipitates from T cells blasts derived from four donors with different DP allotypes. The apparent absence of polymorphism of pX is further suggested by two-dimensional peptide mapping of a single spot derived from 2D-PAGE of 125I-labelled DP deglycosylated immunoprecipitates from two donors.
Collapse
Affiliation(s)
- G Carra
- Istituto di Chimica Biologica, Università di Verona, Italy
| | | | | | | | | | | | | |
Collapse
|
19
|
Sorrentino S, Libonati M. Human pancreatic-type and nonpancreatic-type ribonucleases: a direct side-by-side comparison of their catalytic properties. Arch Biochem Biophys 1994; 312:340-8. [PMID: 8037446 DOI: 10.1006/abbi.1994.1318] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.3] [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: 01/28/2023]
Abstract
The catalytic properties and substrate preference of several highly purified human ribonucleases from different organs and body fluids have been examined in detail using various low-molecular-weight compounds and single- or double-stranded polyribonucleotides as substrates. All single-stranded polyribonucleotides were degraded by nonpancreatic-type (npt) RNases at a slower rate than by pancreatic-type (pt) enzymes: ptRNases were 20 times more active on RNA and poly(U) substrates and more than 6000 times more active on poly(C). Pancreatic-type RNases degraded poly(C) faster than RNA, showing a strong preference for poly(C) over poly(U) with the following activity ratios: RNA/poly(C), 0.44; RNA/poly(U), 12; poly(C)/poly(U), 27. In contrast, nptRNases cleaved RNA more rapidly than synthetic homopolymers, preferring poly(U) over poly(C) with the following ratios: RNA/poly(C), 130; RNA/poly(U), 10; poly(C)/poly(U), 0.08. Human ptRNases degraded poly(A) and double-stranded polyribonucleotides about 100 and 400 times faster, respectively, than bovine RNase A. However, no measurable activity could be detected on these substrates with nptRNases. The activities of ptRNases on dinucleoside phosphates (CpN and UpN) or uridine and cytidine 2',3'-cyclic phosphates were similar to those of bovine RNase A; nptRNases, instead, cleaved only CpA and UpA at an appreciable rate. The effects of pH, ionic strength, and divalent cations on the activity of these ribonucleases were also investigated using yeast RNA as a substrate.
Collapse
Affiliation(s)
- S Sorrentino
- Department of Organic and Biological Chemistry, Faculty of Sciences, University of Naples, Italy
| | | |
Collapse
|
20
|
Gerosa F, Tommasi M, Benati C, Gandini G, Libonati M, Tridente G, Carra G, Trinchieri G. Differential effects of tyrosine kinase inhibition in CD69 antigen expression and lytic activity induced by rIL-2, rIL-12, and rIFN-alpha in human NK cells. Cell Immunol 1993; 150:382-90. [PMID: 8103709 DOI: 10.1006/cimm.1993.1206] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [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: 01/28/2023]
Abstract
The effect of rIL-12 on induction of CD69 antigen expression and cytolytic activity in purified human NK cells was evaluated in comparison to the effects of rIL-2 and rIFN-alpha. It was found that rIL-12 directly induced CD69 antigen expression in NK cells, although the period of incubation required by rIL-12 was longer than the period required by rIL-2 or by rIFN-alpha. Similarly, the cytolytic activity induced by rIL-12 in NK cells against the NK-resistant target cell line Raji was consistently lower than the cytolytic activity induced by rIL-2 or rIFN-alpha when measured after 6 hr of incubation, and increased during the following 18 hr of incubation. To compare the involvement of tyrosin kinases in activation of NK cells induced by rIL-2, rIL-12, and rIFN-alpha, the effect of the specific inhibitor of tyrosin kinases, genistein, was evaluated on induction of CD69 antigen expression and lytic function mediated by the three cytokines. It was found that genistein inhibited CD69 antigen expression induced by rIL-2 and by rIL-12, but not that induced by rIFN-alpha. Unlike the effect on CD69 antigen expression, the cytolytic activity induced by all three cytokines was inhibited by genistein. These results, together with the finding that CD69 antigen expression induced by rIL-2 but not by rIL-12 or rIFN-alpha was inhibited by addition of rIL-4, strongly suggest that IL-2, IL-12, and IFN-alpha mediate their effects, leading to induction of CD69 antigen expression through different activation pathways.
Collapse
Affiliation(s)
- F Gerosa
- Istituto di Immunologia e Malattie Infettive, Policlinico di Borgo Roma, Verona, Italy
| | | | | | | | | | | | | | | |
Collapse
|
21
|
Abstract
Single-strand-preferring ribonucleases of the pancreatic type, structurally and/or catalytically similar to bovine RNase A but endowed with a higher protein basicity, are able to degrade double-stranded RNA (dsRNA) or DNA:RNA hybrids under standard assay conditions (0.15 M NaCl, 0.015 M sodium citrate, pH 7), where RNase A is inactive. This enzyme too, however, becomes quite active if assay conditions are slightly modified or its basicity is increased (polyspermine-RNase). In the attempt to review these facts, we have analyzed and discussed the role that in the process have the secondary structure of dsRNA as well as other variables whose influence has come to light in addition to that of the basicity of the enzyme protein, i.e., the ionic strength, the presence of carbohydrates on the RNase molecule, and the structure (monomeric or dimeric) of the enzyme. A possible mechanism by which dsRNAs are attacked by pancreatic-type RNases has been proposed.
Collapse
Affiliation(s)
- M Libonati
- Istituto di Chimica Biologica, Facoltà di Medicina e Chirurgia, Università di Verona, Italy
| | | |
Collapse
|
22
|
Menegazzi M, Carcereri de Prati A, Ogura T, Columbano A, Ledda-Columbano GM, Libonati M, Esumi H, Suzuki H. Involvement of DNA polymerase beta in proliferation of rat liver induced by lead nitrate or partial hepatectomy. FEBS Lett 1992; 310:135-8. [PMID: 1397262 DOI: 10.1016/0014-5793(92)81314-c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [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: 12/26/2022]
Abstract
We have studied the expression pattern of DNA polymerase beta in two different models of in vivo cell proliferation. Both mRNA levels and enzyme activity of DNA polymerase beta markedly increased before and/or during DNA synthesis in proliferating hepatocytes in mitogen-treated and partially hepatectomized rats. The time-courses of the expression of the gene coding for DNA polymerase beta were significantly different in the two cell systems. A 5-fold increase in DNA polymerase beta mRNA was observed 8 h after lead nitrate administration, i.e. well before the onset of DNA synthesis. In the regenerative liver cells a 3-fold increase in the amount of mRNA was observed 24-48 h after partial hepatectomy, the event being coincident with extensive DNA synthesis. In both systems, the increase of mRNA levels was always paralleled by an increase in enzyme activity, suggesting that DNA polymerase beta activity may be regulated at a pre-translational level.
Collapse
Affiliation(s)
- M Menegazzi
- Istituto di Chimica Biologica, Università di Verona, Italy
| | | | | | | | | | | | | | | |
Collapse
|
23
|
Menegazzi M, Carcereri de Prati A, Miwa M, Suzuki H, Libonati M. Regulation of poly(ADP-ribose) polymerase gene expression in mitogen-stimulated human peripheral blood mononuclear cells. Biochem Int 1992; 26:69-77. [PMID: 1616499] [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] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The level of mRNA for poly(ADP-ribose) polymerase in human PBMC increased 8 h after addition of PHA, reaching its maximum (9-fold over the basal level) 3-4 days after the stimulation and decreasing thereafter. mRNA maximum slightly preceded in time the maximal value of DNA synthesis. The half-life of poly(ADP-ribose) polymerase mRNA, which is 1.2 h in quiescent PBMC, increased up to 3.4 h in stimulated PBMC. This PHA-induced stabilization of the mRNA for poly(ADP-ribose) polymerase could account for the accumulation of the transcript in mitogen-treated PBMC.
Collapse
Affiliation(s)
- M Menegazzi
- Istituto di Chimica Biologica, Università di Verona, Italy
| | | | | | | | | |
Collapse
|
24
|
Suzuki H, Menegazzi M, De Prati AC, Ogura T, Esumi H, Matsukage A, Libonati M. Induction of DNA polymerase beta during proliferation of mitogen-stimulated human lymphocytes. Biochem Biophys Res Commun 1991; 181:623-8. [PMID: 1755846 DOI: 10.1016/0006-291x(91)91236-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [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: 12/28/2022]
Abstract
On induction of proliferation of human peripheral blood mononuclear cells by phytohemagglutinin treatment, DNA polymerase beta activity increases markedly before and during DNA replication. The increase of enzymatic activity seems to be well correlated with the increase of DNA polymerase beta mRNA, which is induced by enhanced expression of the DNA polymerase beta gene. These data suggest that DNA polymerase beta is involved in DNA repair, which is linked to replicative DNA synthesis, or directly in replicative DNA synthesis in normal proliferating cells.
Collapse
Affiliation(s)
- H Suzuki
- Istituto di Chimica Biologica, Università di Verona, Italy
| | | | | | | | | | | | | |
Collapse
|
25
|
Gerosa F, Scardoni M, Tommasi M, Benati C, Snelli L, Gandini G, Libonati M, Tridente G, Carra G. Interferon alpha induces expression of the CD69 activation antigen in human resting NK cells, while interferon gamma and tumor necrosis factor alpha are ineffective. Int J Cancer 1991; 48:473-5. [PMID: 1904052 DOI: 10.1002/ijc.2910480328] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
|
26
|
Gerosa F, Tommasi M, Scardoni M, Accolla RS, Pozzan T, Libonati M, Tridente G, Carra G. Structural analysis of the CD69 early activation antigen by two monoclonal antibodies directed to different epitopes. Mol Immunol 1991; 28:159-68. [PMID: 1707136 DOI: 10.1016/0161-5890(91)90100-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [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: 12/28/2022]
Abstract
The biochemical structure of CD69 early activation antigen has been characterized by means of two newly isolated mAb, namely C1.18 and E16.5. Upon analysis by SDS-PAGE, C1.18-reactive molecules immunoprecipitated from 125I-surface labeled PMA activated PBL consisted of a 32 + 32 kD dimer, a 32 + 26 kD dimer, a 26 + 26 kD dimer and a 21 + 21 kD dimer. E16.5-reactive molecules consisted of a 26 + 26 kD dimer and a 21 + 21 kD dimer. Cross absorption experiments showed that E16.5 mAb reacts with an epitope of the CD69 molecule distinct from the one recognized by C1.18 mAb and present only on a subpopulation of the CD69 molecular pool. The patterns of migration of C1.18- and E16.5-reactive molecules in two-dimensional gel-electrophoresis, under reducing conditions before and after treatment with Endoglycosidase F enzyme suggest that the two mAb recognize the same glycoprotein structure, but in two distinct glycosylation forms, both expressed on the cell surface membrane. Finally, p32, p26 and p21 of CD69 complex obtained from three distinct normal donors did not show appreciable structural polymorphism, by two-dimensional peptide mapping, not only among single subunits within the same individual, but also among homologous subunits in distinct individuals. Further, it was found that CD69 complex is expressed at the cell surface of resting PBL, although at a very reduced level in comparison to PMA activated cells. C1.18 and E16.5 mAb induced comparable cell proliferation and IL-2 production in PBL in the presence of PMA. C1.18 mAb increased intracellular free calcium concn in PMA activated PBL after cross-linking with goat anti mouse Ig, while the effect induced by E16.5 mAb after cross-linking was consistently lower. Finally, it was found that Sepharose-linked C1.18 mAb, in the presence of rIL-2 or PMA, did not induce TNF release from 6 NK cell clones.
Collapse
MESH Headings
- Antibodies, Monoclonal/immunology
- Antigens, CD/chemistry
- Antigens, CD/immunology
- Antigens, Differentiation, T-Lymphocyte/chemistry
- Antigens, Differentiation, T-Lymphocyte/immunology
- Calcium/metabolism
- Cell Membrane/immunology
- Electrophoresis, Gel, Two-Dimensional
- Epitopes
- Glycoproteins/immunology
- Glycoside Hydrolases/pharmacology
- Humans
- In Vitro Techniques
- Killer Cells, Natural/immunology
- Lectins, C-Type
- Lymphocyte Activation
- Lymphocytes/immunology
- Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase
- Molecular Weight
- Peptide Mapping
- Protein Processing, Post-Translational
Collapse
Affiliation(s)
- F Gerosa
- Istituto di Scienze Immunologiche, Università di Verona, Italy
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Sorrentino S, De Prisco R, Libonati M. Human seminal ribonuclease. Immunological quantitation of cross-reactive enzymes in serum, urine and seminal plasma. Biochim Biophys Acta 1989; 998:97-101. [PMID: 2790056 DOI: 10.1016/0167-4838(89)90125-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The distribution of secretory-type ribonuclease in human serum, urine and seminal plasma has been studied by immunological measurements. Inhibition of enzyme activity by antibodies against pure human seminal RNAase shows that a cross-reactive enzyme is predominant (90%) in seminal plasma and is a significant component (70-80%) in urine and serum. A competitive binding radioimmunoassay has been developed by using specific antibodies and 125I-labelled RNAase as radioligand. The procedure, very sensitive, reproducible and specific, has been used to determine seminal RNAase levels in seminal plasma samples from 48 healthy individuals (age range, 20-58 years). The mean concentration of the enzyme was found to be 6.6 micrograms/ml (S.D. +/- 1.9).
Collapse
Affiliation(s)
- S Sorrentino
- Dipartimento di Chimica Organica e Biologica, Facoltà di Scienze, Università di Napoli, Italy
| | | | | |
Collapse
|
28
|
Beintema JJ, Blank A, Schieven GL, Dekker CA, Sorrentino S, Libonati M. Differences in glycosylation pattern of human secretory ribonucleases. Biochem J 1988; 255:501-5. [PMID: 3202829 PMCID: PMC1135256] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The major secretory ribonuclease (RNase) of human urine (RNase HUA) was isolated and sequenced by automatic Edman degradation and analysis of peptides and glycopeptides. The isolated enzyme was shown to be free of other urine RNase activities by SDS/polyacrylamide-gel electrophoresis and activity staining. It is a glycoprotein 128 amino acids long, differing from human pancreatic RNase in the presence of an additional threonine residue at the C-terminus. It differs from the pancreatic enzyme in its glycosylation pattern as well, and contains about 45 sugar residues. Each of the three Asn-Xaa-Ser/Thr sequences (Asn-34, Asn-76, Asn-88) is glycosylated with a complex-type oligosaccharide chain. Glycosylation at Asn-88 has not been observed previously in mammalian secretory RNases. Preliminary sequence data on the major RNase of human seminal plasma have revealed no difference between it and the major urinary enzyme; their similarities include the presence of threonine at the C-terminus. The glycosylation pattern of human seminal RNase is very similar to that of the pancreatic enzyme. The structural differences between the secretory RNases from human pancreas, urine and seminal plasma must originate from organ-specific post-translational modifications of the one primary gene product. Detailed characterization of peptides and the results of gel filtration of tryptic and tryptic/chymotryptic digests of performic acid-oxidized RNase have been deposited as Supplementary Publication SUP 50146 (4 pages) at the British Library Lending Division, Boston Spa, Wetherby, West Yorkshire LS23 7BQ, U.K., from whom copies can be obtained on the terms indicated in Biochem. J. (1988) 249, 5.
Collapse
Affiliation(s)
- J J Beintema
- Biochemisch Laboratorium, Rijksuniversiteit Groningen, The Netherlands
| | | | | | | | | | | |
Collapse
|
29
|
Carsana A, Confalone E, Palmieri M, Libonati M, Furia A. Structure of the bovine pancreatic ribonuclease gene: the unique intervening sequence in the 5' untranslated region contains a promoter-like element. Nucleic Acids Res 1988; 16:5491-502. [PMID: 2838818 PMCID: PMC336780 DOI: 10.1093/nar/16.12.5491] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [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: 01/02/2023] Open
Abstract
Although pancreatic ribonucleases are extensively studied proteins, little information is available on nucleic acids coding for these enzymes. Here, for the first time, the structure of a gene coding for such an enzyme, the well known bovine pancreatic ribonuclease, is reported. The coding region of this gene is devoid of introns, whereas the 5' untranslated sequence of the pancreatic transcript contains an intron of 735 nucleotides. This intervening sequence is endowed with signals (CAAT and TATA boxes) which might act as regulatory elements. The structural organization of this gene suggests that the sequence coding for the bovine pancreatic ribonuclease might be expressed under the control of two different promoters.
Collapse
Affiliation(s)
- A Carsana
- Dipartimento di Chimica Organica e Biologica, Università di Napoli, Italy
| | | | | | | | | |
Collapse
|
30
|
Menegazzi M, Scarpa A, Libonati M. Analysis of the methylation pattern of c-Ha-ras oncogene in human prostatic cancer. Ital J Biochem 1988; 37:104-10. [PMID: 3042687] [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] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
To determine the methylation pattern of c-Ha-ras oncogene in prostatic tissue and to identify possible changes of methylation associated with cancer, high molecular weight DNA was extracted from 7 normal and 6 carcinomatous human prostates. Analysis of the samples was performed by cleaving DNA with the restriction endonucleases Msp I, Hpa II and Cfo I, and by Southern hybridizing the DNA digests with the 32P-labelled c-Ha-ras (pT24-C3) probe. Several discrete fragments were obtained with Hpa II and Cfo I digestion while the Msp I pattern showed fewer and smaller bands. Therefore, c-Ha-ras appears to be partially methylated. While a considerable polymorphism of the sequence 5'-CCGG-3' was observed at several Msp I sites in all cases, no significant differences could be evidenced in the methylation patterns of normal and neoplastic prostatic DNA samples extracted and purified from each patient.
Collapse
Affiliation(s)
- M Menegazzi
- Istituto di Chimica Biologica, Facoltà di Medicina e Chirurgia, Università di Verona
| | | | | |
Collapse
|
31
|
Merli GJ, Weitz H, Martin JH, McClay EF, Adler AG, Fellin FM, Libonati M. Cardiac dysrhythmias associated with ophthalmic atropine. Arch Intern Med 1986; 146:45-7. [PMID: 3942464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Atropine sulfate, a mydriatic and cycloplegic agent, is frequently used in patients undergoing glaucoma surgery. Trabeculectomy with peripheral iridectomy is the most common glaucoma surgery performed to decrease intraocular pressure and preserve vision. Systemic absorption of ophthalmic atropine does occur and may result in toxic and adverse side effects. Cardiac dysrhythmias are one of the major adverse reactions. This case study reviews three patients who had a trabeculectomy for glaucoma and received ophthalmic atropine. One patient received both systemic and ocular atropine. Two patients developed atrial fibrillation and one a supraventricular tachycardia. Two patients required admission to a cardiac intensive care unit for management of the dysrhythmia and a third reverted to normal sinus rhythm spontaneously. The cardiac effects of ophthalmic atropine should be considered in the preoperative and postoperative assessment of patients with dysrhythmias.
Collapse
|
32
|
Abstract
The sequence of a cloned cDNA coding for bovine seminal ribonuclease, an enzyme secreted in the bull seminal vesicles, was determined. The cDNA starts at the amino acid residue 47 and terminates 12 nucleotides beyond the consensus sequence AAUAAA in the 3' non-coding region of the mRNA. Northern blotting analysis shows that the mRNA for bovine seminal ribonuclease consists of about 950 nucleotides, a value that is similar to that of other mRNAs coding for ribonucleases of the pancreatic type.
Collapse
|
33
|
Lavitrano M, Osman AM, Sorrentino S, Libonati M. Base composition of dromedary thymus DNA. Ital J Biochem 1985; 34:322-7. [PMID: 4077466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The base composition of dromedary thymus DNA was determined by reversed-phase HPLC determination of the four major deoxyribonucleosides. No significant differences were found between dromedary and calf thymus DNA. The elution system used (different from that suggested in the literature) was ammonium phosphate buffer/acetonitrile.
Collapse
|
34
|
Sorrentino S, Lavitrano M, De Prisco R, Libonati M. Human seminal ribonuclease. A tool to check the role of basic charges and glycosylation of a ribonuclease in the action of the enzyme on double-stranded RNA. Biochim Biophys Acta 1985; 827:135-9. [PMID: 3967033 DOI: 10.1016/0167-4838(85)90081-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Human seminal ribonuclease (a basic protein occurring in a glycosylated and in a non-glycosylated form) is very active against double-stranded RNAs (De Prisco, R., Sorrentino, S., Leone, E. and Libonati, M. (1984) Biochim. Biophys. Acta 788, 356-363). The action of the two enzyme forms on single-stranded and double-stranded substrates was studied as a function of pH and ionic strength. Results indicate (1) that glycosylation of the RNAase molecule does not affect enzyme action on single-stranded RNAs, while (2) degradation of double-stranded RNAs is moderately increased by the presence of carbohydrates in the enzyme molecule. Human seminal RNAase shows a marked helix-destabilizing activity on poly(dA-dT) X poly(dA-dT). Under various conditions, this action (1) is definitely stronger than that of bovine RNAase A, and (2) seems to be less dependent on the glycosylation than on the basicity of the enzyme protein. The remarkable activity of human seminal RNAase on double-stranded RNA may, at least partly, be related to the enzyme properties mentioned above.
Collapse
|
35
|
De Prisco R, Sorrentino S, Leone E, Libonati M. A ribonuclease from human seminal plasma active on double-stranded RNA. Biochim Biophys Acta 1984; 788:356-63. [PMID: 6466685 DOI: 10.1016/0167-4838(84)90049-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A ribonuclease, active on single- and double-stranded RNAs, has been isolated from human seminal plasma 3-5 micrograms of enzyme were recovered per ml of seminal plasma, equivalent to 71% of total activity and a 2500-fold purification (measured with poly(A) X poly(U) as substrate) from the initial dialyzed material. Similar amounts of RNAase were found per g (wet weight) of human prostate, where the enzyme appears to be produced. Human seminal RNAase degrades poly(U) 3-times faster than poly(A) X poly(U), and poly(C) or viral single-stranded RNA about 10-times faster than poly(U). Degradation of poly(A) X poly(U), viral double-stranded RNA, and poly(A) by human seminal RNAase is 500-, 380- and 140-times more efficient, respectively, than by bovine RNAase A. The enzyme, a basic protein with maximum absorbance at 276 nm, occurs in two almost equivalent forms, one of which is glycosylated. Mr values of the glycosylated and non-glycosylated form are 21000 and 16000, respectively. The amino-acid composition of the RNAase is very similar to that of human pancreatic RNAase. The same is true for the carbohydrate content of its glycosylated form.
Collapse
|
36
|
Carsana A, Lavitrano ML, Libonati M. Proteins with preferential affinity for single-stranded DNA in tissues of Octopus vulgaris lam. Ital J Biochem 1984; 33:88-97. [PMID: 6539759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
An investigation was carried out to search for proteins with preferential affinity for single-stranded DNA in nuclei of testicles, white bodies and optic lobes of Octopus Vulgaris Lam, as examples of organs characterized by high meiotic, high mitotic, and no or low mitotic activity, respectively. The results obtained are the following. Single strand binding proteins are present in testicles nuclei and, in much lower amount, in white bodies nuclei. Testicles cells have at least three protein species with affinity for single-stranded DNA, which, on the basis of elution characteristics and electrophoretic mobility, appear to be specific of testicle tissue. No single strand binding proteins could be found in Octopus optic lobes nuclei.
Collapse
|
37
|
Abstract
Native bovine seminal ribonuclease is a dimeric protein, whose identical subunits (Mr 14500), linked through two disulfide bridges, can be dissociated by a selective reduction procedure. Evidence is presented that the synthesis in vitro, under reducing conditions, of bovine seminal RNAase, directed by polyadenylated RNA isolated from bull seminal vesicles (where the enzyme is synthesized in vivo), occurs in the form of a precursor, 18000-Da polypeptide. The precursor nature of this translation product was deduced by two criteria: (1) its specific immunoprecipitation with anti-bovine seminal RNAase antibodies; (2) its processing by dog pancreas microsomal membranes to produce a protein with a molecular weight similar to that of the subunit(s) of bovine seminal RNAase. Moreover, evidence is offered that the precursor polypeptide is able to form in vitro a dimeric molecule under conditions where no exogenous reducing agents were added.
Collapse
|
38
|
Carsana A, Furia A, Libonati M. Influence of protein net charge on the nucleic acid helix-destabilizing activity of various pancreatic ribonucleases. Mol Cell Biochem 1983; 56:89-92. [PMID: 6685223 DOI: 10.1007/bf00228773] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Helix-destabilization of double-stranded poly[d(A-T)]induced by various homologous pancreatic ribonucleases which differ in their net charges has been studied under different ionic strength conditions. The response of the destabilizing activity of the various proteins to ionic strength is represented by bell-shaped curves, whose maxima are shifted to higher ionic strength values the higher the number of positive charges of the RNAase involved in the nucleic acid-protein complex. This observation is discussed, and a model proposed, that could explain the experimental results presented.
Collapse
|
39
|
Sorrentino S, Yakovlev GI, Libonati M. Dimerization of deoxyribonuclease I, lysozyme and papain. Effects of ionic strength on enzymic activity. Eur J Biochem 1982; 124:183-9. [PMID: 6282587 DOI: 10.1111/j.1432-1033.1982.tb05923.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Transition of bovine ribonuclease A from its monomeric to a dimeric form changes the pattern of enzymic activity response to ionic strength [Sorrentino, S., Carsana, A., Furia, A., Doskocil, J., and Libonati, M. (1980) Biochim. Biophys. Acta. 609, 40-52]. To see whether this phenomenon could be common to other enzyme-substrate systems, the action of various dimeric and monomeric enzymes (ox pancreas deoxyribonuclease, hog spleen acid deoxyribonuclease, bovine seminal ribonuclease, egg-white lysozyme, and papain) on polyelectrolytic substrates has been studied under different conditions of ionic strength. Dimerization of ox pancreas deoxyribonuclease, lysozyme and papain was obtained by cross-linkage with dimethyl suberimidate. The main results of the investigation, similar to those obtained with ribonuclease A, are the following. 1. Enzyme monomers and dimers show markedly different patterns of activity response to ionic strength at given pH values: the reactions catalyzed by monomeric enzymes are highly modulated by salt, whereas those catalyzed by dimeric enzymes are not. In particular, at the reaction optimum the monomeric form of an enzyme is significantly more active than the dimeric one. 2. The optimum of the reaction catalyzed by a dimeric enzyme is shifted to higher ionic strengths in comparison with that of the reaction catalyzed by a monomeric enzyme. A model is proposed that could explain these results on the basis of the influence of ionic strength on the intramolecular dynamics of the enzyme molecule and its non-specific interactions with polyelectrolytic substrates.
Collapse
|
40
|
Carsana A, Furia A, Gallo A, Beintema JJ, Libonati M. Nucleic acid-protein interactions. Degradation of double-stranded RNA by glycosylated ribonucleases. Biochim Biophys Acta 1981; 654:77-85. [PMID: 7272311 DOI: 10.1016/0005-2787(81)90138-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
1. Extensively glycosylated ribonucleases, like the enzymes from pig and horse pancreas, show a much higher activity on double-stranded RNAs than similarly charged, carbohydrate-free RNAases under stranded assay conditions (relatively high salt concentrations). Glycosylated pig and horse pancreas RNAases also show a larger destabilizing effect on double-stranded poly[d(A-T)] X poly[d(A-T)], than that displayed by bovine RNAase A under these conditions. Both activities show a similar dependence on the ionic strength of the medium. 2. A partial enzymic removal of the heterosaccharide side chains from pig and horse RNAases reduces but their degradative activity on double-stranded RNA and their destabilizing action on poly[d(A-T)] X poly[d(A-T)]. 3. These results are tentatively correlated with a modification of the microenvironment of the enzyme protein caused by its extensive glycosylation.
Collapse
|
41
|
|
42
|
Sorrentino S, Carsana A, Furia A, Doskocil J, Libonati M. Ionic control of enzymic degradation of double-stranded RNA. Biochim Biophys Acta 1980; 609:40-52. [PMID: 6250614 DOI: 10.1016/0005-2787(80)90199-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The pattern of the degradation of various double-stranded polyribonucleotides by several ribonucleases (bovine RNAase A and its cross-linked dimer, bovine seminal RNAase, and pike-whale pancreatic RNAase) has been studied as a function of ionic strength and pH. It appears that (1) there is no direct correlation between the secondary structure of double-stranded RNA and its resistance against enzymatic breakdown, i.e., the stability of the secondary structure of double-helical RNA is not the main variable in the process. (2) The acstivity responses of the enzymes examined to changes of ionic strength and pH suggest that enzymic degradation of double-stranded RNA is mainly controlled by ion concentration, and that the process may fall within the phenomena interpreted by the theory of the ionic control of biochemical reactions advanced by Douzou and Maurel (Douzou, P. and Maurel, P. (1977) Proc. Natl. Acad. Sci. U.S.A. 74, 1013--1015). (3) The activity curves of the enzyme studied show, at a given pH, a shift toward higher ionic strengths as a function of the basicity of the enzyme protein. This finding explains the already observed correlation between number and/or density of positive charges of a ribonuclease molecule and its ability to attack double-stranded RNA in 0.15 M sodium chloride/0.015 M sodium citrate (SSC). (4) A careful analysis of the influence of ionic strength and pH on the reaction appears to be necessary in order to characterize a ribonuclease which shows activity towards double-stranded RNAs, and to allow a meaningful comparison between different enzymes capable of attacking these substrates.
Collapse
|
43
|
Abstract
High molecular weight, fully double-stranded RNA (dsRNA) has been recognized as the genetic material of many plant, animal, fungal, and bacterial viruses (Diplornaviruses): virusspecific dsRNA is also found in cells infected with single-stranded RNA viruses. DsRNA has identified in a variety of apparently normal eucaryotic cells and is associated with the "killer" character of certain strains of Saccaromyces cerevisiae.
Collapse
|
44
|
Gallo A, Sorrentino S, Iorio S, Libonati M. [Analysis of deoxyribonuclease I and II activity as a function of ionic strength and pH]. Boll Soc Ital Biol Sper 1979; 55:2006-11. [PMID: 45303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The action of deoxyribonucleases I and II has been studied as a function of ionic strength and pH, in the light of the theory of the ionic control of biochemical reactions (P. Douzou and P. Maurel (1977) Proc. Nat. Acad. Sci. USA, 74, 1013-1015). The pattern of DNA degradation by the two enzymes fits the general principles of the theory. However, the activity of DNAase II, a dimeric, basic protein (pI = 10,2) appears to be scarcely modulated by variables such as ionic strength and pH. This is reminiscent of what was elsewhere observed with the system double stranded RNA-seminal RNAase (also a very basic, dimeric enzyme), and could, therefore, tentatively be correlated with the dimeric and/or the very basic nature of the enzyme protein.
Collapse
|
45
|
Furia A, Carsana A, Libonati M. [DNA-protein interactions. Destabilizing activity of sheep pancreatic RNAase]. Boll Soc Ital Biol Sper 1979; 55:261-7. [PMID: 233346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Evidence is presented that ovine pancreatic ribonuclease, a protein strictly homologous to bovine RNAase A but with one positive charge less, has a definite 'destabilizing' activity (quite similar to that of the bovine enzyme) on double-stranded DNA. This action of sheep pancreas RNAase has been measured by differential spectrophotometry and determining the thermal-transition profiles of the protein-DNA complexes.
Collapse
|
46
|
Libonati M, Palmieri M. How much is secondary structure responsible for resistance of double-stranded RNA to pancreatic ribonuclease A? Biochim Biophys Acta 1978; 518:277-89. [PMID: 26405 DOI: 10.1016/0005-2787(78)90184-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
1. Double-stranded f2 sus11 or Qbeta RNAs, resistant to bovine pancreatic RNAase A in 0.15 M NaCl/0.015 M sodium citrate (SSC), are quickly and completely degraded at 10-fold lower ionic strength (0.1 X SSC) under otherwise similar conditions. At this ionic strength the secondary structure of double-stranded RNA is maintained, as judged by the following: (a) the unchanged resistance of double-stranded RNA and DNA, under similar low ionic strength conditions, to nuclease S1 from Aspergillus oryzae, in contrast with the sensitivity of the corresponding denatured nucleic acids to this enzyme, specific for single-stranded RNA and DNA; (b) the co-operative pattern of the thermal-transition profile of double-stranded RNA (with a Tm of 89 degrees C) in 0.1 X SSC. 2. Whereas in SSC bovine seminal RNAase (RNAase BS-1) and whale pancreatic RNAase show an activity on double-stranded RNA significantly higher than that of RNAase A, in 0.1 X SSC the activity of the latter enzyme on this substrate becomes distinctly higher than that of RNAase BS-1, and similar to that of whale RNAase. 3. From these results it is deduced that the secondary structure is probably not the only nor the most important variable in determining the susceptibility double-stranded RNA to ribonuclease. Other factors, such as the effect of ionic strength on the enzyme and/or the binding of enzyme to nucleic acids, may play an important role in the process of double-stranded RNA degradation by ribonucleases specific for single-stranded RNA.
Collapse
|
47
|
Libonati M, Beintema JJ. Basic charges on ribonuclease molecules and activity towards double-stranded polyribonucleotides. Biochem Soc Trans 1977; 5:470-4. [PMID: 902866 DOI: 10.1042/bst0050470] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
48
|
Sorrentino S, Palmieri M, Libonati M. [Influence of the ionic strength on the effect of monomeric and dimeric RNAse on poly(A)]. Boll Soc Ital Biol Sper 1977; 53:461-5. [PMID: 20909] [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: 12/12/2022]
|
49
|
Parente A, Palmieri M, De Prisco R, Libonati M. [Relationship between the basicity of the ribonuclease molecule and the degradation of double spiral RNA: recent contribution]. Boll Soc Ital Biol Sper 1977; 53:466-70. [PMID: 911502] [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: 12/24/2022]
|
50
|
Palmieri M, Libonati M. Differential, structure-dependent susceptibility of poly(A) and RNA to monomeric and dimeric pancreatic ribonuclease A. Biochim Biophys Acta 1977; 474:456-66. [PMID: 12819 DOI: 10.1016/0005-2787(77)90274-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cross-linked dimers of bovine RNAase A are definitely more efficient than monomers at degrading polyadenylic acid under conditions of ionic strength and pH, where the polymer assumes either a double-helical or an ordered single-stranded, base-stacked structure. The opposite occurs, i.e., monomers of RNAase A are definitely more active than dimers,when poly(A) is digested by the two enzyme species under conditions where the conformation of the polymer is essentially that of a random coil. The same pattern of events occurs when total RNA from Escherichia coli or single-stranded RNA of f2 sus11 bacteriophage are used as substrates under opposite ionic-strength conditions. In the presence of high salt concentrations, favouring the formation and the stability of a secondary structure in self-complementary sequences of RNA, the ribonucleic acids are degraded at a higher rate by dimers than by monomers of bovine RNAase A. The opposite occurs in the presence of very low salt concentrations, i.e. when the RNAs are in solution presumably as random coils. These observations are discussed in the light of a hypothesis already advanced to understand the mechanism of enzymic degradation of secondary structures of polyribonucleotides.
Collapse
|