51
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Saumweber H, Frasch M, Korge G. Two puff-specific proteins bind within the 2.5 kb upstream region of the Drosophila melanogaster Sgs-4 gene. Chromosoma 1990; 99:52-60. [PMID: 2160364 DOI: 10.1007/bf01737289] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Drosophila nuclear proteins Bj6 and Bx42 characterized previously are detected in a series of developmentally active puffs on salivary gland chromosomes. Here the binding of both proteins at puff 3C11-12 containing the glue protein gene Sgs-4 is described in more detail. By deletion analysis we show that both proteins bind within a chromosomal segment containing 17-19 kb of DNA surrounding the Sgs-4 gene. They are detectable at this site during the intermoult stages, before the puff regresses in response to the moulting hormone ecdysone. If the Sgs-4 gene together with flanking DNA sequences is brought into a different chromosomal position by P element transfer, both proteins are detected at this new location. Both proteins are bound to the chromosome within the range of 2.5 kb DNA upstream of the Sgs-4 gene. A strain containing a 52 bp deletion within this region fails to bind Bx42 protein suggesting that the missing DNA, which overlaps a hypersensitive region, may be required for the binding of the Bx42 protein.
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Affiliation(s)
- H Saumweber
- Institut für Entwicklungsphysiologie Universität zu Köln, Federal Republic of Germany
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52
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Schuldt C, Kloetzel PM, Bautz EK. Molecular organization of RNP complexes containing P11 antigen in heat-shocked and non-heat-shocked Drosophila cells. EUROPEAN JOURNAL OF BIOCHEMISTRY 1989; 181:135-42. [PMID: 2496981 DOI: 10.1111/j.1432-1033.1989.tb14704.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Immunofluorescence analysis of polytene chromosomes of Drosophila melanogaster using the monoclonal antibody P11 has shown that after heat-shock the 38-kDa P11 antigen almost exclusively localizes at heat-shock puff 93D where it is part of giant puff-specific RNP granules. The biochemical experiments reported here show that, independent of growth temperature, the P11 antigen is a component of nuclear 10S RNP particles. The P11-containing 10S snRNPs can be stabilized in CsCl with 20 mM Mg2+ and possess a buoyant density of rho = 1.4 g/cm3. Sucrose gradient analysis of nuclear RNP extracts of heat-shocked Schneider's S-3 tissue culture cells shows that, after a 37 degree C heat-shock, the 10S RNPs associate with large RNP complexes sedimenting at 170-220S. The change in distribution is a temperature-dependent process with intermediate forms at 29 degrees C and 33 degrees C. In thermotolerant cells this observed change in distribution is strongly reduced. DEAE-Sephacel column chromatography and sucrose gradient analysis of nuclear RNP, followed by Northern blot analysis using 93D-specific probes of the TaqI repeat and immunoblotting experiments, show that the P11-containing 10S snRNPs are distinct from the RNP complexes formed by the 93D transcripts, suggesting an indirect association after heat-shock. Our experiments demonstrate that, despite the fact that a 37 degrees C heat-shock does not affect the overall integrity of nuclear RNP, it imposes changes on the general organization and interaction of the nuclear RNP population, resulting in the formation of large nuclear RNP aggregates and complexes. Such changes may be important for the survival strategy of the cell and for hnRNA processing and storage events which are effected by heat-shock.
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Affiliation(s)
- C Schuldt
- Zentrum für Molekulare Biologie und Institut für Molekulare Genetik der Universität Heidelberg, Federal Republic of Germany
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53
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Fleischmann B, Filipski R, Fleischmann G. Isolation and distribution of a Drosophila protein preferentially associated with active regions of the genome. Chromosoma 1989; 97:381-9. [PMID: 2498046 DOI: 10.1007/bf00292765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
A non-histone chromosomal protein of Mr = 75,000 was isolated from Drosophila embryos. The distribution pattern of this protein was determined by indirect immunofluorescence on salivary gland chromosomes of Drosophila melanogaster third instar larvae and compared with the distribution pattern of RNA polymerase II. Despite its preferential association with transcriptionally active regions of the chromosomes there was in many cases an almost inverse correlation with the RNA polymerase II content of a given locus. We postulate a function of the Mr = 75,000 protein in posttranscriptional regulation of gene expression by storing the newly synthesized RNA.
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Affiliation(s)
- B Fleischmann
- Lehrstuhl für Biochemie, Ruhr-Universität, Bochum, Federal Republic of Germany
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54
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Frasch M, Saumweber H. Two proteins from Drosophila nuclei are bound to chromatin and are detected in a series of puffs on polytene chromosomes. Chromosoma 1989; 97:272-81. [PMID: 2495915 DOI: 10.1007/bf00371966] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Immunizing chromatin protein fractions from Drosophila melanogaster embryos, monoclonal antibodies have been generated against two nuclear proteins of different molecular weight. These proteins are present in a chromatin fraction of Drosophila Kc-cell nuclei and both proteins could be shown to cosediment with nucleosomes following separation on sucrose gradients. Early in development both proteins are located in the embryo cytoplasm. Later, at times when transcription starts at blastoderm, they become redistributed into the nuclei. On salivary gland chromosomes both proteins are detected in a series of developmentally active puffs. The number of sites where these antigens can be detected, as well as the qualitative properties of the antigens at these sites differ between both proteins.
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Affiliation(s)
- M Frasch
- Max Planck Institut für Entwicklungsbiologie Abt. 1, Tübingen, Federal Republic of Germany
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55
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Ragghianti M, Bucci S, Mancino G, Lacroix JC, Boucher D, Charlemagne J. A novel approach to cytotaxonomic and cytogenetic studies in the genus Triturus using monoclonal antibodies to lampbrush chromosomes antigens. Chromosoma 1988. [DOI: 10.1007/bf00327370] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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56
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Zusman SB, Sweeton D, Wieschaus EF. short gastrulation, a mutation causing delays in stage-specific cell shape changes during gastrulation in Drosophila melanogaster. Dev Biol 1988; 129:417-27. [PMID: 3138149 DOI: 10.1016/0012-1606(88)90389-2] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Mutations at the short gastrulation locus affect the timing of certain early morphogenetic events occurring during gastrulation in Drosophila melanogaster. Specifically, the invagination and subsequent closing of the posterior midgut and the anterior midgut appear to be delayed in these embryos. In addition, their germbands do not extent the full distance anteriorly on the dorsal side of the embryo. The dorsal cells are abnormally thick and fall into extremely deep dorsal folds as the germband extends. sog embryos continue development, but form disorganized first instar larvae. Normal sog expression is required in the zygote, but not in the mother for normal embryonic development and viability. Analysis of adult and larval gynandromorphs indicates that sog expression is required only in the ventral and/or anterior and posterior ends of the embryo, arguing that the dorsal abnormalities caused by the mutation are secondary consequences of defects elsewhere in mutant embryos.
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57
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Lutz Y, Jacob M, Fuchs JP. The distribution of two hnRNP-associated proteins defined by a monoclonal antibody is altered in heat-shocked HeLa cells. Exp Cell Res 1988; 175:109-24. [PMID: 3278913 DOI: 10.1016/0014-4827(88)90259-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A monoclonal antibody obtained after mice were immunized with hnRNP purified from HeLa cells recognizes two polypeptides of Mr 35,000 and 37,000. By immunocytofluorescence, these antigens can be visualized only in cells previously heat shocked at 45 degrees C for 5 or 10 min, although they are present at the same level in unstressed and stressed cells. The signal, which is mostly concentrated in the interchromatin space, where hnRNP fibrils are located, does not accumulate with time and disappears 4 to 5 h after heat shock. Discrimination between the two types of hnRNP substructures, the 30-50 S monoparticles and the nuclear matrix fibrils, based on differential sensitivity to salt or ribonuclease treatment, showed that in unstressed cells the antigens behave as monoparticle proteins. In contrast, in heat-shocked cells, most 35-37K antigens behave as nuclear matrix proteins. Thus, heat shock seems to induce a rapid and reversible switch of these two antigens from hnRNP monoparticles to the nuclear matrix. The data demonstrate that heat shock, which was previously shown not to alter the overall RNA: protein packaging ratio of hnRNP, induces subtle modifications of their substructure. Such modifications might be of importance since heat shock is known for instance to affect pre-mRNA processing.
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Affiliation(s)
- Y Lutz
- Laboratoire de Génétique Moléculaire des Eucaryotes du CNRS, Strasbourg, France
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58
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Nigg EA. Nuclear function and organization: the potential of immunochemical approaches. INTERNATIONAL REVIEW OF CYTOLOGY 1988; 110:27-92. [PMID: 3053500 DOI: 10.1016/s0074-7696(08)61847-1] [Citation(s) in RCA: 59] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- E A Nigg
- Swiss Institute for Experimental Cancer Research, Chemin des Boveresses, Epalinges s/Lausanne
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59
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Fleischmann G, Filipski R, Elgin SC. Isolation and distribution of a Drosophila protein preferentially associated with inactive regions of the genome. Chromosoma 1987; 96:83-90. [PMID: 3125020 DOI: 10.1007/bf00285889] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The distribution patterns of chromosomal proteins from Drosophila can be observed by immunofluorescent staining of the polytene chromosomes from larval salivary glands. We have purified a non-histone chromosomal protein of Mr = 69,000 molecular weight which has a high affinity for DNA with little sequence specificity. Immunofluorescent staining indicates that this protein is preferentially associated with the inactive portions of the genome, including the centric heterochromatin and the condensed bands within the euchromatic arms of the chromosomes. Observation of both the heat shock loci 87A and 87C and the developmentally regulated loci 74EF and 75B shows an inverse correlation between immunofluorescent staining for the Mr = 69,000 protein and for RNA polymerase. The presence of this protein appears to be correlated with the packaging of the chromatin in an inactive form.
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Affiliation(s)
- G Fleischmann
- Lehrstuhl für Biochemie, Ruhr-Universität, Bochum, Federal Republic of Germany
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60
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Lakomek HJ, Schwochau M, Decken K, Juli E, Will H, Krüskemper HL. Attempts towards a serological diagnosis of ankylosing spondylitis. Clin Rheumatol 1987; 6 Suppl 2:67-72. [PMID: 3319358 DOI: 10.1007/bf02203387] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Polytene chromosomes of salivary glands as well as nuclear proteins from Kc-cells of Drosophila melanogaster have been used as substrate to identify and evaluate the diagnostic value of crossreacting antibodies present in sera of AS patients. The diagnostic significance of the recently described anti-93D antibody (Lakomek et al., 1984) was confirmed by screening sera of patients with definite or suspected AS using cytoimmunofluorescence on the polytene chromosomes. In addition, four new antibodies could be identified in AS sera by immunoblotting. Simultaneous detection of these antibodies supports the diagnosis of AS and is most useful in diagnosis of early stages of this disease.
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Affiliation(s)
- H J Lakomek
- Department of Medicine C, University of Düsseldorf, West Germany
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61
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Roth MB, Gall JG. Monoclonal antibodies that recognize transcription unit proteins on newt lampbrush chromosomes. J Biophys Biochem Cytol 1987; 105:1047-54. [PMID: 3308902 PMCID: PMC2114812 DOI: 10.1083/jcb.105.3.1047] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
We prepared hybridoma cell lines from mice injected with newt germinal vesicle proteins. We tested culture supernates from these cell lines for antibodies that bound to specific morphological structures in lampbrush chromosome preparations (nucleoli, loops, chromomeres, etc.). Four mAbs that recognize antigens on the lateral transcription loops are described here. We suggest that these antigens are proteins associated with nascent RNA transcripts, although they are not among the 30-40-kD "core" heterogeneous nuclear ribonucleoproteins.
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Affiliation(s)
- M B Roth
- Department of Embryology, Carnegie Institution, Baltimore, Maryland 21210
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62
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Hochstrasser M. Chromosome structure in four wild-type polytene tissues of Drosophila melanogaster. The 87A and 87C heat shock loci are induced unequally in the midgut in a manner dependent on growth temperature. Chromosoma 1987; 95:197-208. [PMID: 3111801 DOI: 10.1007/bf00330351] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
A systematic screen of wild-type Drosophila melanogaster larval organs has revealed three tissues besides the salivary gland with suitable polyteny for detailed cytogenetic analysis: the prothoracic gland, hindgut, and middle midgut. Chromosome banding patterns are very similar between tissues, but puffing patterns show considerable differences. In intact nuclei, oblique substructural elements can sometimes be detected in bands from some of the tissues. As a way of exploiting these newly characterized chromosomes, the heat shock puff response in midgut cells has been studied in detail. The puffing pattern is very similar to that in salivary glands, but an unexpected difference is found in the relative activity of the 87A7 and 87C1 loci, which contain the hsp70 genes. When larvae are raised at 16 degrees C, heat shocks ranging from 10 to 60 min induce only a weak midgut puff at 87A7 that is much smaller than that at 87C1, in contrast to other tissues where both are strongly induced. In pulse-labeled nuclei, an approximately five fold difference in transcriptional activity at the two loci is observed. However, when larvae are raised at 25 degrees C, the converse is found: the 87A7 puff is large, and little or no puffing is detectable at 87C1. Thus, in the midgut, heat shock induced puffing at these two loci is inversely modulated by a mechanism dependent on growth temperature.
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63
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Identification of a nonhistone chromosomal protein associated with heterochromatin in Drosophila melanogaster and its gene. Mol Cell Biol 1987. [PMID: 3099166 DOI: 10.1128/mcb.6.11.3862] [Citation(s) in RCA: 354] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Monoclonal antibodies were prepared against a fraction of nuclear proteins of Drosophila melanogaster identified as tightly binding to DNA. Four of these antibodies were directed against a 19-kilodalton nuclear protein; immunofluorescence staining of the polytene chromosomes localized the antigen to the alpha, beta, and intercalary heterochromatic regions. Screening of a lambda gt11 cDNA expression library with one of the monoclonal antibodies identified a recombinant DNA phage clone that produced a fusion protein immunologically similar to the heterochromatin-associated protein. Polyclonal sera directed against the bacterial lacZ fusion protein recognized the same nuclear protein on Western blots. A full-length cDNA clone was isolated from a lambda gt10 library, and its DNA sequence was obtained. Analysis of the open reading frame revealed an 18,101-dalton protein encoded by this cDNA. Two overlapping genomic DNA clones were isolated from a Charon 4 library of D. melanogaster with the cDNA clone, and a restriction map was obtained. In situ hybridization with these probes indicated that the gene maps to a single chromosome location at 29A on the 2L chromosome. This general strategy should be effective for cloning the genes and identifying the genetic loci of chromosomal proteins which cannot be readily assayed by other means.
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64
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Hill RJ, Mott MR, Steffensen DM. The preparation of polytene chromosomes for localization of nucleic acid sequences, proteins, and chromatin conformation. INTERNATIONAL REVIEW OF CYTOLOGY 1987; 108:61-118. [PMID: 2444550 DOI: 10.1016/s0074-7696(08)61436-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- R J Hill
- CSIRO Division of Molecular Biology, North Ryde, NSW, Australia
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65
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Glätzer KH, Kloetzel PM. Differential chromosomal distribution of ribonucleoprotein antigens in nuclei of Drosophila spermatocytes. J Cell Biol 1986; 103:2113-9. [PMID: 3536959 PMCID: PMC2114595 DOI: 10.1083/jcb.103.6.2113] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
The ribonucleoprotein (RNP) composition of the active Y chromosomal structures in spermatocyte nuclei of Drosophila hydei has been investigated using the anti-RNP antibodies Dm 28K2 and pp60 as a probe. Antibody Dm 28K2 was raised against an RNP protein of cytoplasmic RNP particles in D. melanogaster cells, while antibody pp60 was raised against a pre-messenger RNP fraction from oocytes of Xenopus laevis. Both antibodies detect nuclear RNP (nRNP) antigens of D. hydei. This is shown by CsCl density centrifugation of nRNP from D. hydei cells and immunoblotting across the density gradient. Dm 28K2 and pp60 recognize antigens of nRNP complexes which band at a characteristic buoyant density of approximately 1.4 g/cm3 in CsCl. By indirect immunofluorescence we observe that the nRNP complexes identified by Dm 28K2 are localized at only two of the five Y chromosomal loop structures which are named according to their distinct morphology. Dm 28K2 decorates RNPs within the "clubs," within the cones, and within the matrix of the "pseudonucleolus." Ultrastructural bodies that are candidates for this immunoreaction are RNP granules that resemble the so-called perichromatin granules. Antibody pp60 recognizes RNP complexes close to the axes of the active Y chromatin. In the "pseudonucleolus" it can be shown that the structures recognized by pp60 are quite distinct from those detected by Dm 28K2. Thus, the "pseudonucleolus" is a striking example for the presence of different RNP populations within a same defined nuclear compartment. Together with previous results (Glätzer, K. H., 1984, Mol. Gen. Genet., 196:236-243), our data represent evidence that the morphological and apparently functional differences between the active Y chromosomal loops, which are involved in male fertility, are caused by the presence of qualitatively and possibly also functionally different RNP populations within these nuclear compartments. Because both RNP antigens are discussed in the literature in connection with repressed mRNP the observed cross-reaction of the respective antibodies in D. hydei suggests a more general and important function of these proteins in the RNA metabolism of eukaryotic cells.
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66
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James TC, Elgin SC. Identification of a nonhistone chromosomal protein associated with heterochromatin in Drosophila melanogaster and its gene. Mol Cell Biol 1986; 6:3862-72. [PMID: 3099166 PMCID: PMC367149 DOI: 10.1128/mcb.6.11.3862-3872.1986] [Citation(s) in RCA: 217] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Monoclonal antibodies were prepared against a fraction of nuclear proteins of Drosophila melanogaster identified as tightly binding to DNA. Four of these antibodies were directed against a 19-kilodalton nuclear protein; immunofluorescence staining of the polytene chromosomes localized the antigen to the alpha, beta, and intercalary heterochromatic regions. Screening of a lambda gt11 cDNA expression library with one of the monoclonal antibodies identified a recombinant DNA phage clone that produced a fusion protein immunologically similar to the heterochromatin-associated protein. Polyclonal sera directed against the bacterial lacZ fusion protein recognized the same nuclear protein on Western blots. A full-length cDNA clone was isolated from a lambda gt10 library, and its DNA sequence was obtained. Analysis of the open reading frame revealed an 18,101-dalton protein encoded by this cDNA. Two overlapping genomic DNA clones were isolated from a Charon 4 library of D. melanogaster with the cDNA clone, and a restriction map was obtained. In situ hybridization with these probes indicated that the gene maps to a single chromosome location at 29A on the 2L chromosome. This general strategy should be effective for cloning the genes and identifying the genetic loci of chromosomal proteins which cannot be readily assayed by other means.
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67
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The localisation of an Mr 74,000 major chromatin antigen on native salivary chromosomes of Drosophila melanogaster. Chromosoma 1986. [DOI: 10.1007/bf00292753] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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68
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Greiser-Wilke I, Moennig V, Thon D, Rauter K. Characterization of monoclonal antibodies against Brucella melitensis. ZENTRALBLATT FUR VETERINARMEDIZIN. REIHE B. JOURNAL OF VETERINARY MEDICINE. SERIES B 1985; 32:616-27. [PMID: 3907209 DOI: 10.1111/j.1439-0450.1985.tb02002.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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69
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Lacroix JC, Azzouz R, Boucher D, Abbadie C, Pyne CK, Charlemagne J. Monoclonal antibodies to lampbrush chromosome antigens of Pleurodeles waltlii. Chromosoma 1985; 92:69-80. [PMID: 3891248 DOI: 10.1007/bf00327246] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Germinal vesicles of oocytes from Pleurodeles waltlii were used for immunization of BALB/c mice to obtain hybridomas secreting monoclonal antibodies. The hybridomas were screened for reactivity of their antibodies against lampbrush chromosomes of oocytes, as revealed by indirect immunostaining. Antibodies labelling the lampbrush chromosomes were also tested on histological sections of oocytes, embryos, and larvae of Pleurodeles. Characterization of the antigens was accomplished through immunoblotting of two-dimensional electrophoretic gels of germinal vesicle proteins. The ten monoclonal antibodies giving a positive reaction were classed into five groups. Group 1, exemplified by antibody A33, recognizes all the lampbrush chromosome transcribing sites (loops). Moreover, it differentially labels the cell nuclei during embryonic and larval development. Group 2, antibody B71, also stains all the loops of the lampbrush chromosomes, but does not react with cell nuclei of embryos and larvae. Group 3, antibody A1, labels specific loops, some of which are heterozygous in the strain of P. waltlii used. These heterozygosities have allowed us to localize and to characterize a chromosomal segment on bivalent IV which is heteromorphic in the two partners of the bivalent. We suggest that this heteromorphism represents a morphological distinction between Z and W heterochromosomes. Moreover, this antibody reacts with only one transcription unit along a loop that contains several units. Group 4, antibody B24, stains the only two structures in the lampbrush chromosomes of P. waltlii that do not have a loop organization, the mass "M" and the spheres. Group 5, antibody A35, reacts with the chromomeres. The antigens corresponding to antibodies A33 and B24 have been identified as proteins, which have apparent molecular weights of 80 and 104 kilodaltons, respectively. They correspond to proteins abundant in the germinal vesicles. All the antibodies described here cross-react with the lampbrush chromosomes of five other species of Urodeles.
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70
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Lukàcs N, Thiel HJ, Mettenleiter TC, Rziha HJ. Demonstration of three major species of pseudorabies virus glycoproteins and identification of a disulfide-linked glycoprotein complex. J Virol 1985; 53:166-73. [PMID: 2578194 PMCID: PMC255000 DOI: 10.1128/jvi.53.1.166-173.1985] [Citation(s) in RCA: 82] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The glycoproteins of pseudorabies virus (PRV) Phylaxia were characterized with monoclonal antibodies as specific reagents. Three major structural glycoproteins with molecular weights of 155,000 (155K) (gC), 122K (gA), and 90K (gB) could be identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under nonreducing conditions. We investigated the processing of glycoproteins gA, gB, and gC by in vitro translation, pulse-chase experiments, and in the presence of the ionophore monensin which inhibits glycosylation. gA and gB were found to compose a single polypeptide, whereas gC was found to be a disulfide-linked glycoprotein complex. Immunoprecipitates formed with the aid of anti-gC monoclonal antibodies gave rise to three glycoprotein bands (gC0 [120K], gC1 [67K], and gC2 [58K]) by sodium dodecyl sulfate-polyacrylamide gel electrophoresis under reducing conditions. Limited proteolysis of gC0, gC1, and gC2 resulted in peptide maps of gC0 related to those of both gC1 and gC2. No common peptide bands between gC1 and gC2, however, were seen. We suggest that (i) gC1 and gC2 arise by proteolytic cleavage from the same precursor molecule and stay joined via disulfide bridges and (ii) gC0 is an uncleaved precursor.
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71
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Fleischmann G, Pflugfelder G, Steiner EK, Javaherian K, Howard GC, Wang JC, Elgin SC. Drosophila DNA topoisomerase I is associated with transcriptionally active regions of the genome. Proc Natl Acad Sci U S A 1984; 81:6958-62. [PMID: 6095263 PMCID: PMC392055 DOI: 10.1073/pnas.81.22.6958] [Citation(s) in RCA: 160] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The distribution of DNA topoisomerase I within Drosophila polytene chromosomes was observed by immunofluorescent staining with affinity-purified antibodies. The enzyme is preferentially associated with active loci, as shown by prominent staining of puffs. The heat shock loci 87A-87C are stained after, but not before, heat shock induction. A detailed comparison of the distribution of topoisomerase I with that of RNA polymerase II reveals a similar, although not identical, pattern of association. Topoisomerase I is also found in association with the nucleolus, the site of transcription by RNA polymerase I.
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72
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Abstract
Eukaryotic chromatin has a dynamic, complex hierarchical structure. Active gene transcription takes place on only a small proportion of it at a time. While many workers have tried to characterize active chromatin, we are still far from understanding all the biochemical, morphological and compositional features that distinguish it from inactive nuclear material. Active genes are apparently packaged in an altered nucleosome structure and are associated with domains of chromatin that are less condensed or more open than inactive domains. Active genes are more sensitive to nuclease digestions and probably contain specific nonhistone proteins which may establish and/or maintain the active state. Variant or modified histones as well as altered configurations or modifications of the DNA itself may likewise be involved. Practically nothing is known about the mechanisms that control these nuclear characteristics. However, controlled accessibility to regions of chromatin and specific sequences of DNA may be one of the primary regulatory mechanisms by which higher cells establish potentially active chromatin domains. Another control mechanism may be compartmentalization of active chromatin to certain regions within the nucleus, perhaps to the nuclear matrix. Topological constraints and DNA supercoiling may influence the active regions of chromatin and be involved in eukaryotic genomic functions. Further, the chromatin structure of various DNA regulatory sequences, such as promoters, terminators and enhancers, appears to partially regulate transcriptional activity.
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73
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Shallal A, Campbell AM. A monoclonal antibody (HNo-g7) with specificity for a human nucleolar protein. Biosci Rep 1984; 4:789-95. [PMID: 6210117 DOI: 10.1007/bf01128821] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
A murine monoclonal antibody which reacts strongly with the nucleoli of human epithelial cells has been isolated. The antibody is of the IgM class and the antigen has a molecular weight of 45 000. The antibody appears to react with interphase chromatin only and to have specificity for epithelial cells.
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74
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Glätzer KH. Preservation of nuclear RNP antigens in male germ cell development of Drosophila hydei. ACTA ACUST UNITED AC 1984. [DOI: 10.1007/bf00328055] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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75
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Dequin R, Saumweber H, Sedat JW. Proteins shifting from the cytoplasm into the nuclei during early embryogenesis of Drosophila melanogaster. Dev Biol 1984; 104:37-48. [PMID: 6428951 DOI: 10.1016/0012-1606(84)90034-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Monoclonal antibodies have been used to study the distribution of several proteins in cleavage and blastoderm stages of Drosophila melanogaster. These antigens are known to be associated with hnRNA-containing particles in tissue culture cells. Protein blotting shows that they are present in the embryo 1 hr after egg deposition. A redistribution from the cytoplasm into the somatic nuclei can be observed during developmental stage 12/13, one stage prior to the formation of the cellular blastoderm. Yolk nuclei become stained by these antibodies at about the same time. The shift into pole cell nuclei, however, occurs 1 1/2 hr later, during the migration of these cells into the posterior midgut rudiment.
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76
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Hulsebos TJ, Hackstein JH, Hennig W. Lampbrush loop-specific protein of Drosophila hydei. Proc Natl Acad Sci U S A 1984; 81:3404-8. [PMID: 6587357 PMCID: PMC345516 DOI: 10.1073/pnas.81.11.3404] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
By immunofluorescence techniques and protein blotting experiments we have shown that an antiserum specifically reacts with a Mr 80,000 protein (the "Ps protein") in the lampbrush loop " pseudonucleolus " in spermatocyte nuclei of Drosophila hydei. Comparative studies of X/Y and X/0 testes indicate that the gene encoding the Ps protein is not located on the Y chromosome but on an autosome or the X chromosome. The Ps protein is tissue specific. It is likely to be a rather conserved protein since the antigenic determinant recognized by the antiserum could be detected in the spermatocyte nuclei of a number of other Drosophila species. For those species with prominent Y chromosomal lampbrush loops, it could be shown that the cross-reaction is, as in D. hydei, associated with a specific Y chromosomal loop.
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77
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Mathog D, Hochstrasser M, Gruenbaum Y, Saumweber H, Sedat J. Characteristic folding pattern of polytene chromosomes in Drosophila salivary gland nuclei. Nature 1984; 308:414-21. [PMID: 6424026 DOI: 10.1038/308414a0] [Citation(s) in RCA: 126] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
A computer-based system for recording and analysing light microscope images, combined with classical cytogenetic analysis, has revealed the spatial organization of the giant chromosomes of Drosophila salivary gland cells. Each polytene chromosome arm folds up in a characteristic way, contacts the nuclear surface at specific sites and is topologically isolated from all other arms.
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78
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Laskov R, Muller S, Hochberg M, Giloh H, Van Regenmortel MH, Eilat D. Monoclonal autoantibodies to histones from autoimmune NZB/NZW F1 mice. Eur J Immunol 1984; 14:74-81. [PMID: 6198184 DOI: 10.1002/eji.1830140114] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Fusion of spleen cells from autoimmune NZB/NZW female mice with drug-resistant myeloma cells (clones NSI/1, X63-Ag8.653 and NSO/1) produced hybrid clones which secreted antibodies to various nuclear components. Roughly 50% of the anti-nuclear hybridomas produced antibodies reacting with DNA, 20% with RNA and 30% reacted with other nuclear antigens. Two hybridomas of the latter group were cloned and studied in detail. They secreted antibodies which produced bright fluorescence staining of nuclei and metaphase chromosomes. The specificity of the antibodies was determined by testing them in an enzyme-linked immunosorbent assay and a radioimmunoassay against individual acid- and salt-extracted histones, against histones mixed two and three at a time and against histone complexes isolated as such from chromatin. One of the monoclonal antibodies was specific for histone H2B and reacted with the histone free in solution or when present as a H2A-H2B complex. The second monoclonal antibody recognized a specific conformation in the H3-H4 complex that was present only when the complex was obtained from chromatin by salt extraction. The same conformation, however, could be induced by adding histone H2B to a mixture of acid-extracted H3 and H4. Our findings show that the autoimmune syndrome in NZB/NZW mice resembles human systemic lupus erythematosus not only in the incidence of antibodies to DNA and RNA, but also in the production of autoantibodies to histones.
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79
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Dangli A, Bautz EK. Differential distribution of nonhistone proteins from polytene chromosomes of Drosophila melanogaster after heat shock. Chromosoma 1983; 88:201-7. [PMID: 6414786 DOI: 10.1007/bf00285621] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Nine monoclonal antibodies directed against chromosomal proteins of D. melanogaster were used to study, by indirect immunofluorescence, the distribution of their respective antigens on polytene chromosomes following heat shock. This treatment is known to induce a specific set of transcriptionally active puffs with concomitant reduction of transcriptional activity in previously active loci. Our studies revealed wide differences in the distribution of the individual chromosomal proteins under heat shock conditions with regard to pattern and rate of both elimination from the inactivated loci and accumulation in the activated loci.
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80
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Bhorjee JS, Barclay SL, Wedrychowski A, Smith AM. Monoclonal antibodies specific for tight-binding human chromatin antigens reveal structural rearrangements within the nucleus during the cell cycle. J Cell Biol 1983; 97:389-96. [PMID: 6350316 PMCID: PMC2112543 DOI: 10.1083/jcb.97.2.389] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
The class of nonhistone chromosomal proteins that remains bound to DNA in chromatin in the presence of 2.5 M NaCl-5 M urea has proven refractile to biochemical analysis. In order to study its role in chromatin organization, we have produced monoclonal antibodies that are specific for the HeLa DNA-protein complex that remains after extraction of chromatin with high salt and urea. The antibody-producing clones were identified with an ELISA assay. Of the six clones selected, five were stabilized by limiting dilution. All clones are IgG producers. None cross-react significantly with native DNA, core histones, or the high-mobility group nonhistone proteins. All antibodies are specific for nuclear or juxtanuclear antigens. Indirect immunofluorescence shows that three antibodies, which are nonidentical, stain three different nuclear networks. Available evidence indicates that two of these networks are the nuclear matrix. A fourth antibody reveals structures reminiscent of chromocenters. A fifth antibody, AhNA-1, binds to interphase HeLa chromatin and specifically decorates metaphase chromosomes. AhNA-1 similarly recognizes rat chromosomes. Each of these monoclonal antibodies also reveals a changing pattern of nuclear staining as cells progress through the cell cycle. Presumably, this reflects the rearrangement of the cognate antigens.
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81
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Risau W, Symmons P, Saumweber H, Frasch M. Nonpackaging and packaging proteins of hnRNA in Drosophila melanogaster. Cell 1983; 33:529-41. [PMID: 6407757 DOI: 10.1016/0092-8674(83)90434-8] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
Monoclonal antibodies have previously been raised against chromosomal proteins of Drosophila. Using a biochemical fractionation method for the isolation of large hnRNA-containing structures (hnRNP) of Drosophila tissue culture cells, we show that seven of these antibodies recognize different antigens, and that these antigens are associated with RNA. Analysis of the sedimentation behavior of antigen-containing structures in sucrose gradients reveals that the antigens are differentially distributed with respect both to one another and to pulse-labeled RNA. We demonstrate that the antigens are minor components of hnRNP and are different from the major Drosophila hnRNP packaging proteins, which we have also identified. The antigens are probably involved in the processing of hnRNA in the nucleus.
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82
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83
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Abstract
Little is known about factors which control the outgrowth of neurites in the central nervous system (CNS) during development, although in vitro studies with neurones from the peripheral nervous system have shown that neurites require an appropriate substrate and specific factors for growth. To investigate the role of cell-surface components in the development of the CNS, we have raised a series of monoclonal antibodies against membrane components of cells from the visual system of the chick embryo. We report here that one of these antibodies, T61/3/12, clearly inhibits axonal outgrowth from chick retinal explants but does not affect axon growth from the peripheral nervous system.
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84
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Turner BM. Immunofluorescent staining of human metaphase chromosomes with monoclonal antibody to histone H2B. Chromosoma 1982; 87:345-57. [PMID: 6761099 DOI: 10.1007/bf00327635] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
A mouse monoclonal IgM antibody against the core histone H2B has been shown, by indirect immunofluorescence, to stain metaphase chromosomes from a variety of cultured cell types. Experiments carried out with human HeLa cells showed that the intensity of staining varied along the length of chromosome arms giving in some cases a rudimentary banded staining pattern. Considerable variation in staining intensity was noted between individual chromosomes and between different metaphase spreads. It was noted that chromosomes having a more swollen appearance stained more intensely than those with a more compact structure, which were often unstained. Preincubation of unfixed metaphase chromosomes in buffered salt solutions virtually eliminated the cell to cell and chromosome to chromosome variation in staining, even when no visible effect on chromosome morphology was caused by such treatment. It is concluded that the determinant recognised by antibody HBC-7 is ubiquitous but is inaccessible in some chromosomes or chromosome regions. Digestion of purified chromatin (primarily interphase) with DNAase 1 or micrococcal nuclease resulted in a several-fold increase in the binding of antibody HBC-7 measured by solid-phase radioimmunoassay. This increase was abolished by subsequent treatment with trypsin, which suggests that the antigenic determinant recognised by antibody HBC-7 lies in the trypsin-sensitive N-terminal region of nucleosomal H2B. As the cationic N-terminal regions of the core histones are involved in DNA binding, it is likely that the accessibility of the determinant recognised by antibody HBC-7 is influenced by the relationship between the core histones and their associated DNA.
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85
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Kane CM, Cheng PF, Burch JB, Weintraub H. Tissue-specific and species-specific monoclonal antibodies to avian red cell nuclear proteins. Proc Natl Acad Sci U S A 1982; 79:6265-9. [PMID: 6959116 PMCID: PMC347101 DOI: 10.1073/pnas.79.20.6265] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
In order to identify potential red cell-specific regulatory proteins and to define additional red cell-specific markers, we have isolated a series of hybridomas that produce monoclonal antibodies that react with nuclear preparations from avian red blood cells. Several antibodies have been well characterized for their tissue- and species-specific reactions by using solid-phase and protein-transfer radioimmunoassays as well as immunofluorescence. These antibodies should allow isolation and characterization of individual nuclear proteins that are tissue and species specific and may prove useful for the study of gene expression in the erythropoietic system. The majority of the well-characterized antibodies appear to have tissue-specific properties. However, three antibodies react with all tested chicken tissues; one of these reacts with multiple peptides in a pattern that varies qualitatively and quantitatively between the tissues. This may reflect a common protein domain or modification that is used in several different tissues for similar functions but is nevertheless present in an overall protein framework that is tissue specific. Because the major fraction of the hybridomas initially produced is tissue specific, we presume that the immune system selects for tissue-specific determinants. This property of the immune system may prove to be a useful general feature of this type of analysis.
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86
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Kabisch R, Krause J, Bautz EK. Evolutionary changes in non-histone chromosomal proteins within the Drosophila melanogaster group revealed by monoclonal antibodies. Chromosoma 1982; 85:531-8. [PMID: 6813057 DOI: 10.1007/bf00327348] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Monoclonal antibodies directed against nonhistone chromosomal proteins of D. melanogaster were tested for crossreactivity with the homologous antigens of various Drosophila species. -- By indirect immunofluorescence it could be shown that three antibodies react only with polytene chromosomes of species of the D. melanogaster subgroup, and only much less with chromosomes of other species of Drosophila. -- With chromosomes of various other species of the Sophophora or Drosophila radiations only a reaction at background level could be observed. The results suggest that the three antibodies react with different antigenic determinants of a single protein whose conformation changed rather fast during evolution of the Drosophilidae.
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87
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Sass H, Bautz EK. Immunoelectron microscopic localization of RNA polymerase B on isolated polytene chromosomes of Chironomus tentans. Chromosoma 1982; 85:633-42. [PMID: 6751713 DOI: 10.1007/bf00330777] [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: 01/21/2023]
Abstract
RNA polymerase B (or II) was localized by immunoelectron microscopy in ultrathin sections of polytene chromosomes isolated from larval salivary glands of Chironomus tentans. The enzyme was found at decondensed sites (puffs and interbands), whereas no detectable RNA polymerase B was present in condensed loci (bands). Within each of the large puffs the highest enzyme concentration was observed wherever the chromatin was in the most decondensed state. Otherwise the enzyme appeared homogeneously distributed within puffs and interbands. This immunoelectron microscopic study, along with the recently published immunofluorescent and autoradiographic analysis of isolated Chironomus chromosomes (Sass, 1982) unequivocally demonstrates that RNA polymerase B is present in most, if not all interbands.
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88
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McCormack M, Dunn JH, Campbell AM. Solid-phase radioimmunoassay of cell specific chromosomal proteins. J Immunol Methods 1982; 49:151-7. [PMID: 6175702 DOI: 10.1016/0022-1759(82)90273-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
A solid-phase radioimmunoassay has been developed for the detection of cell specific chromosomal proteins which require the presence of DNA for their immunoreactivity. The assay involves the binding of chromatin particles sonicated under highly controlled conditions to PVC plates followed by first and second antibody with extensive detergent washing. The sensitivity and specificity of the assay system compares favourably with the complement fixation technique.
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89
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Fisher PA, Berrios M, Blobel G. Isolation and characterization of a proteinaceous subnuclear fraction composed of nuclear matrix, peripheral lamina, and nuclear pore complexes from embryos of Drosophila melanogaster. J Cell Biol 1982; 92:674-86. [PMID: 6177701 PMCID: PMC2112026 DOI: 10.1083/jcb.92.3.674] [Citation(s) in RCA: 179] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Morphologically intact nuclei have been prepared from embryos of Drosophila melanogaster by a simple and rapid procedure. These nuclei have been further treated with high concentrations of DNase I and RNase A followed by sequential extraction with 2% Triton X-100 and 1 M NaCl to produce a structurally and biochemically distinct preparation designated Drosophila subnuclear fraction I (DSNF-I). As seen by phase-contrast microscopy, DSNF-I is composed of material which closely resembles unfractionated nuclei; residual internal nuclear structures including nucleolar remnants are clearly visible. By transmission electron microscopy, nuclear lamina, pore complexes, and a nuclear matrix are similarly identified. Biochemically, DSNF-I is composed almost entirely of protein (greater than 93%). SDS PAGE analysis reveals several major polypeptides; species at 174,000, 74,000, and 42,000 predominate. A polypeptide coincident with the Coomassie Blue-stainable 174-kdalton band has been shown by a novel technique of lectin affinity labeling to be a glycoprotein; a glycoprotein of similar or identical molecular weight has been found to be a component of nuclear envelope fractions isolated from the livers of rats, guinea pigs, opossums, and chickens. Antisera against several of the polypeptides in DSNF-I have been obtained from rabbits, and all of them show only little or no cross-reactivity with Drosophila cytoplasmic fractions. Initial results of immunocytochemical studies, while failing to positively localize either the 174- or 16-kdalton polypeptides, demonstrate a nuclear localization of the 74-kdalton antigen in all of several interphase cell types obtained from both Drosophila embryos and third-instar larvae.
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90
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Cartwright IL, Abmayr SM, Fleischmann G, Lowenhaupt K, Elgin SC, Keene MA, Howard GC. Chromatin structure and gene activity: the role of nonhistone chromosomal proteins. CRC CRITICAL REVIEWS IN BIOCHEMISTRY 1982; 13:1-86. [PMID: 6751690 DOI: 10.3109/10409238209108709] [Citation(s) in RCA: 154] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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91
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Nordheim A, Pardue ML, Lafer EM, Möller A, Stollar BD, Rich A. Antibodies to left-handed Z-DNA bind to interband regions of Drosophila polytene chromosomes. Nature 1981; 294:417-22. [PMID: 6796893 DOI: 10.1038/294417a0] [Citation(s) in RCA: 302] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Antibodies which are specific to the Z-DNA conformation have been purified and characterized on the basis of their binding to three different DNA polymers which can form this left-handed helix. These antibodies bind specifically to polytene chromosomes of Drosophila melanogaster as visualized by fluorescent staining. The staining is found in the interband regions and its intensity varies among different interbands in a reproducible manner. This is the first identification of the Z-DNA conformation in material of biological origin.
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92
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93
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Falkner FG, Saumweber H, Biessmann H. Two Drosophila melanogaster proteins related to intermediate filament proteins of vertebrate cells. J Cell Biol 1981; 91:175-83. [PMID: 6795212 PMCID: PMC2111953 DOI: 10.1083/jcb.91.1.175] [Citation(s) in RCA: 85] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Monoclonal antibodies were prepared against a 46,000 mol wt major cytoplasmic protein from Drosophila melanogaster Kc cells. These antibodies reacted with the 46,000 and a 40,000 mol wt protein from Kc cells. Some antibodies showed cross-reaction with 55,000 (vimentin) and 52,000 mol wt (desmin) proteins from baby hamster kidney (BHK) cells that form intermediate sized filaments in vertebrate cells. In indirect immunofluorescence, the group of cross reacting antibodies stained a filamentous meshwork in the cytoplasm of vertebrate cells. In Kc cells the fluorescence seemed to be localized in a filamentous meshwork that became more obvious after the cells had flattened out on a surface. These cytoskeletal structures are heat-labile; the proteins in Kc or BHK cells rearrange after a brief heat shock, forming juxtanuclear cap structures.
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94
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Will H, Lakomek HJ, Bautz EK. Reaction of human auto-antibodies with antigens of polytene chromosomes of Drosophila. Exp Cell Res 1981; 134:129-40. [PMID: 6788575 DOI: 10.1016/0014-4827(81)90470-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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95
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Risau W, Saumweber H, Symmons P. Monoclonal antibodies against a nuclear membrane protein of Drosophila. Localization by indirect immunofluorescence and detection of antigen using a new protein blotting procedure. Exp Cell Res 1981; 133:47-54. [PMID: 6786899 DOI: 10.1016/0014-4827(81)90355-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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96
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Howard GC, Abmayr SM, Shinefeld LA, Sato VL, Elgin SC. Monoclonal antibodies against a specific nonhistone chromosomal protein of Drosophila associated with active genes. J Cell Biol 1981; 88:219-25. [PMID: 6782108 PMCID: PMC2111725 DOI: 10.1083/jcb.88.1.219] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Hybridomas secreting monoclonal antibodies have been produced by fusion of NS-1 mouse myeloma cells with the spleen cells of mice inoculated with a 60-65,000-mol wt fraction of proteins released from Drosophila embryo nuclei treated with DNase I. The antibodies secreted by the hybridomas were examined with polytene chromosomes of formaldehyde-fixed salivary gland squashes by an immunofluorescence assay. Most of the clonal antibodies obtained resulted in specific staining of the chromosomes relative to the cytoplasmic debris. In the case of clone 28, the antibodies showed a preferential association with sites of gene activity, both puffs and loci identified as puffing at some time during the third instar and prepupal period. In larvae that were heat shocked (exposed to 35 degrees C for 15 min before removal and fixation of the glands), the antibodies of clone 28 stained preferentially the induced heat-shock loci while continuing to stain most of the normal set of loci. The antigen for clone 28 was identified as a single protein of approximately 62,000 mol wt by using the antibodies followed by 125I-rabbit anti-mouse Ig to stain nitrocellulose replicas of SDS polyacrylamide gels of total chromosomal proteins. This study demonstrates that monoclonal antibodies can be used successfully in immunofluorescence staining of formaldehyde-fixed polytene chromosomes. The results verify the hypothesis that a specific nonhistone chromosomal protein is preferentially associated with the set of loci that includes both active sites and those scheduled to be active at some time in this developmental program. Such proteins may play a general role in the mechanisms of cell determination and gene activation.
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97
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Tissue specific nuclear antigens in the germinal vesicle ofXenopus laevis oocytes. ACTA ACUST UNITED AC 1981; 190:197-207. [DOI: 10.1007/bf00848303] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/1981] [Accepted: 05/01/1981] [Indexed: 10/26/2022]
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