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Michelle Rosado - One of the best experts on this subject based on the ideXlab platform.
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Homogeneously Staining Region in anthracycline resistant hl 60 ar cells not associated with mdr1 amplification
Cancer Research, 1992Co-Authors: James E Gervasoni, Robert N Taub, Ming Tsung Yu, Dorothy Warburton, Marlene Sabbath, Stephanie Gilleran, Donald L Coppock, John Dalessandri, Sindu Krishna, Michelle RosadoAbstract:Abstract Anthracycline-resistant HL-60/AR cells and their drug-sensitive HL-60/S counterparts were characterized by karyotypic analysis and examined for the overexpression of DNA and mRNA sequences coding for P-glycoprotein (Pgp). The HL-60/S cells were karyotypically stable over a 5-year period of study (1986–1991), except for an additional small Giemsa-positive band noted at 7q22 in cultures harvested in 1987, but not in 1986. This change did not affect drug sensitivity. The drug-resistant HL-60/AR cells examined in 1986, 1987, and 1991 demonstrated a very stable karyotype. The most striking feature was a large Homogeneously Staining Region in the long arm of chromosome 7 (7q11.2), and translocation of the remainder of the long arm to another centromere. Other changes in the HL-60/AR cells included inversion in 9q, partial deletion of the short arm of chromosome 10p, addition of material to the p arm of der(16), loss of chromosome 22, and the appearance of a new marker chromosome. Both HL-60/S and the HL-60/AR cells were found not to amplify DNA or mRNA sequences coding for the Pgp. Thus, although the HL-60/AR cells possess the classical multidrug resistance phenotype and demonstrate a Homogeneously Staining Region near the Region of the MDR1 gene, their resistance is due to mechanisms other than those coded for by MDR1.
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Homogeneously Staining Region in anthracycline-resistant HL-60/AR cells not associated with MDR1 amplification.
Cancer Research, 1992Co-Authors: James E Gervasoni, Robert N Taub, Ming Tsung Yu, Dorothy Warburton, Marlene Sabbath, Stephanie Gilleran, Donald L Coppock, Sindu Krishna, John D'alessandri, Michelle RosadoAbstract:Abstract Anthracycline-resistant HL-60/AR cells and their drug-sensitive HL-60/S counterparts were characterized by karyotypic analysis and examined for the overexpression of DNA and mRNA sequences coding for P-glycoprotein (Pgp). The HL-60/S cells were karyotypically stable over a 5-year period of study (1986–1991), except for an additional small Giemsa-positive band noted at 7q22 in cultures harvested in 1987, but not in 1986. This change did not affect drug sensitivity. The drug-resistant HL-60/AR cells examined in 1986, 1987, and 1991 demonstrated a very stable karyotype. The most striking feature was a large Homogeneously Staining Region in the long arm of chromosome 7 (7q11.2), and translocation of the remainder of the long arm to another centromere. Other changes in the HL-60/AR cells included inversion in 9q, partial deletion of the short arm of chromosome 10p, addition of material to the p arm of der(16), loss of chromosome 22, and the appearance of a new marker chromosome. Both HL-60/S and the HL-60/AR cells were found not to amplify DNA or mRNA sequences coding for the Pgp. Thus, although the HL-60/AR cells possess the classical multidrug resistance phenotype and demonstrate a Homogeneously Staining Region near the Region of the MDR1 gene, their resistance is due to mechanisms other than those coded for by MDR1.
Walther Traut - One of the best experts on this subject based on the ideXlab platform.
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Zoogeography of the Chromosome 1 HSR in Natural Populations of the House Mouse (Mus Musculus)
Hereditas, 2004Co-Authors: Sergel Agulnik, Heinz Winking, Sabine Adolph, Walther TrautAbstract:: A polymorphism of the central part of chromosome 1 has been described from natural populations of the house mouse (Mus musculus). The Region shows up as a C band-positive Homogeneously Staining Region (HSR) under the light microscope. M. m. domesticus mice carry single band HSRs, whereas M. m. musculus animals have double band HSRs. HSR size variations have been described in both subspecies. The frequency of the HSR chromosome 1 in populations varies from 4% to 81%, but none of the large samples examined consisted only of homozygotes. In the subspecies M. m. domesticus, HSRs were found in North Africa and Western Europe, mainly in the hilly Regions of Southern Germany and Switzerland. Localities with double HSRs are distributed all over the area of M. m. musculus. Based on the population data presented and DNA similarity of different HSRs, the origin and distribution of HSR chromosomes in the house mouse are discussed.
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Restoration of the Mendelian transmission ratio by a deletion in the mouse chromosome 1 HSR.
Genetics Research, 1998Co-Authors: Dieter Weichenhan, Walther Traut, Barbel Kunze, Heinz WinkingAbstract:Summary The house mouse, Mus musculus , harbours a variable cluster of long-range repeats in chromosome1. As shown in previous studies, some high-copy clusters such as the MUT cluster arecytogenetically apparent as a Homogeneously Staining Region (HSR) and are associated with adistortion of the Mendelian recovery ratio when transmitted by heterozygous females. The effect iscaused by a decreased viability of ›}› embryos. It is compensated by maternal or paternal MUT . In this study, a deletion derivative of MUT , MUT del , shows normal transmission ratios andno compensating capability. In this respect, MUT del behaves like a wild-type cluster. Hence, bothproperties – transmission ratio distortion and compensating capability – map to the deleted Region.The deletion comprises three-quarters of the MUT HSR and does not extend to the nearestmarkers adjacent to the HSR. 1. Introduction Chromosome 1 of the house mouse ( Mus musculus )contains a cluster of long-range repeats (LRR; C100 kb repeat length) with variable copy numbers(locus
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an inherited Homogeneously Staining Region derived from a long range repeat family in the house mouse
1994Co-Authors: Walther Traut, Heinz Winking, Christoph Plass, Dieter Weichenhan, Barbel Kunze, Thomas Hellwig, S AgulnikAbstract:Homogeneously Staining Regions (HSRs) are extra chromosome segments of variable size which contain amplified DNA and — as their name implies — stain more or less Homogeneously with G-banding techniques (Biedler and Spengler 1976). They are rather well known from somatic cells. In cell cultures, they can be selected for with drugs like methotrexate (Schimke et al. 1980), and they are found in tumors like neuroblastomas (Alitalo and Schwab 1986). While the origin of classical chromosome aberrations e.g. inversions or translocations is mostly well described by the “breakage and fusion” theory (Muller 1938), no such general theory applies to HSRs. We have to choose among several hypotheses (see Windle and Wahl 1992).
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a long range repeat cluster in chromosome 1 of the house mouse mus musculus and its relation to a germline Homogeneously Staining Region
Genomics, 1992Co-Authors: L Purmann, Heinz Winking, Christoph Plass, M Gruneberg, Walther TrautAbstract:Abstract The laboratory mouse C57BL genome contains about 50 copies of a long-range repeat DNA family clustered in the C-D Region of chromosome 1. The repeat length is more than 50 kb and includes sequences homologous to at least two mRNAs. There are small differences in the copies of this repeat family such as restriction site mutations and gross differences like rearrangements and insertions of LINE1 elements. A germline Homogeneously Staining Region occurring as a chromosome 1 polymorphism in many feral populations of the house mouse is an amplified version of this long-range repeat cluster.
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transcripts from amplified sequences of an inherited Homogeneously Staining Region in chromosome 1 of the house mouse mus musculus
Molecular and Cellular Biology, 1991Co-Authors: Werner A Eckert, Christoph Plass, Walther Traut, Andreas Weith, Heinz WinkingAbstract:: Several populations of the house mouse, Mus musculus, are polymorphic for the presence or absence of an inherited Homogeneously Staining Region (HSR) in chromosome 1. The HSR consists of highly amplified DNA sequences, present in low copy numbers in the HSR- genome. A cloned HSR-derived genomic sequence detected transcripts of about 1.3 and 4.5 kb on blots of poly(A)+ RNA from liver of HSR+ mice but not from that of HSR- mice. A cDNA library was established from RNA of HSR+ mice and screened with the HSR-derived genomic clone. Positive clones were isolated and shown to be complementary to the 1.3-kb RNA species and to amplified DNA sequences in the HSR+ genome. The combined sequence of four overlapping cloned cDNAs is 959 nucleotides long and includes an open reading frame encoding a putative protein of 208 amino acids. The pertinent gene is unidentified. No homologous sequence is stored in the EMBL data base. A stretch of 109 nucleotides at the 3' end of the 1.3-kb RNA homology Region in the same genomic fragment, as indicated by hybridization data and sequence motifs resembling promoter elements. Thus, our data suggest that at least two genes or gene families are encoded in the HSR.
Heinz Winking - One of the best experts on this subject based on the ideXlab platform.
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Zoogeography of the Chromosome 1 HSR in Natural Populations of the House Mouse (Mus Musculus)
Hereditas, 2004Co-Authors: Sergel Agulnik, Heinz Winking, Sabine Adolph, Walther TrautAbstract:: A polymorphism of the central part of chromosome 1 has been described from natural populations of the house mouse (Mus musculus). The Region shows up as a C band-positive Homogeneously Staining Region (HSR) under the light microscope. M. m. domesticus mice carry single band HSRs, whereas M. m. musculus animals have double band HSRs. HSR size variations have been described in both subspecies. The frequency of the HSR chromosome 1 in populations varies from 4% to 81%, but none of the large samples examined consisted only of homozygotes. In the subspecies M. m. domesticus, HSRs were found in North Africa and Western Europe, mainly in the hilly Regions of Southern Germany and Switzerland. Localities with double HSRs are distributed all over the area of M. m. musculus. Based on the population data presented and DNA similarity of different HSRs, the origin and distribution of HSR chromosomes in the house mouse are discussed.
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Restoration of the Mendelian transmission ratio by a deletion in the mouse chromosome 1 HSR.
Genetics Research, 1998Co-Authors: Dieter Weichenhan, Walther Traut, Barbel Kunze, Heinz WinkingAbstract:Summary The house mouse, Mus musculus , harbours a variable cluster of long-range repeats in chromosome1. As shown in previous studies, some high-copy clusters such as the MUT cluster arecytogenetically apparent as a Homogeneously Staining Region (HSR) and are associated with adistortion of the Mendelian recovery ratio when transmitted by heterozygous females. The effect iscaused by a decreased viability of ›}› embryos. It is compensated by maternal or paternal MUT . In this study, a deletion derivative of MUT , MUT del , shows normal transmission ratios andno compensating capability. In this respect, MUT del behaves like a wild-type cluster. Hence, bothproperties – transmission ratio distortion and compensating capability – map to the deleted Region.The deletion comprises three-quarters of the MUT HSR and does not extend to the nearestmarkers adjacent to the HSR. 1. Introduction Chromosome 1 of the house mouse ( Mus musculus )contains a cluster of long-range repeats (LRR; C100 kb repeat length) with variable copy numbers(locus
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an inherited Homogeneously Staining Region derived from a long range repeat family in the house mouse
1994Co-Authors: Walther Traut, Heinz Winking, Christoph Plass, Dieter Weichenhan, Barbel Kunze, Thomas Hellwig, S AgulnikAbstract:Homogeneously Staining Regions (HSRs) are extra chromosome segments of variable size which contain amplified DNA and — as their name implies — stain more or less Homogeneously with G-banding techniques (Biedler and Spengler 1976). They are rather well known from somatic cells. In cell cultures, they can be selected for with drugs like methotrexate (Schimke et al. 1980), and they are found in tumors like neuroblastomas (Alitalo and Schwab 1986). While the origin of classical chromosome aberrations e.g. inversions or translocations is mostly well described by the “breakage and fusion” theory (Muller 1938), no such general theory applies to HSRs. We have to choose among several hypotheses (see Windle and Wahl 1992).
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a long range repeat cluster in chromosome 1 of the house mouse mus musculus and its relation to a germline Homogeneously Staining Region
Genomics, 1992Co-Authors: L Purmann, Heinz Winking, Christoph Plass, M Gruneberg, Walther TrautAbstract:Abstract The laboratory mouse C57BL genome contains about 50 copies of a long-range repeat DNA family clustered in the C-D Region of chromosome 1. The repeat length is more than 50 kb and includes sequences homologous to at least two mRNAs. There are small differences in the copies of this repeat family such as restriction site mutations and gross differences like rearrangements and insertions of LINE1 elements. A germline Homogeneously Staining Region occurring as a chromosome 1 polymorphism in many feral populations of the house mouse is an amplified version of this long-range repeat cluster.
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transcripts from amplified sequences of an inherited Homogeneously Staining Region in chromosome 1 of the house mouse mus musculus
Molecular and Cellular Biology, 1991Co-Authors: Werner A Eckert, Christoph Plass, Walther Traut, Andreas Weith, Heinz WinkingAbstract:: Several populations of the house mouse, Mus musculus, are polymorphic for the presence or absence of an inherited Homogeneously Staining Region (HSR) in chromosome 1. The HSR consists of highly amplified DNA sequences, present in low copy numbers in the HSR- genome. A cloned HSR-derived genomic sequence detected transcripts of about 1.3 and 4.5 kb on blots of poly(A)+ RNA from liver of HSR+ mice but not from that of HSR- mice. A cDNA library was established from RNA of HSR+ mice and screened with the HSR-derived genomic clone. Positive clones were isolated and shown to be complementary to the 1.3-kb RNA species and to amplified DNA sequences in the HSR+ genome. The combined sequence of four overlapping cloned cDNAs is 959 nucleotides long and includes an open reading frame encoding a putative protein of 208 amino acids. The pertinent gene is unidentified. No homologous sequence is stored in the EMBL data base. A stretch of 109 nucleotides at the 3' end of the 1.3-kb RNA homology Region in the same genomic fragment, as indicated by hybridization data and sequence motifs resembling promoter elements. Thus, our data suggest that at least two genes or gene families are encoded in the HSR.
H. Winking - One of the best experts on this subject based on the ideXlab platform.
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Evolution of a long-range repeat family in Chromosome 1 of the genus Mus
Mammalian Genome, 1993Co-Authors: S Agulnik, C. Plass, W. Traut, H. WinkingAbstract:Copy numbers and variation of a clustered long-range repeat family on Chromosome (Chr) 1 have been studied in different species of the genus Mus . The repeat sequence was present in all, as inferred from cross-hybridization with probes derived from the Mus musculus repeat family. Copy numbers determined by dot blot hybridization were very low, from three to six per haploid genome in M. caroli, M. cervicolor , and M. cookii . These species form one branch of the phylogenetic tree in the genus Mus . In the other group of phylogenetically related species— M. spicilegus, M. spretus, M. musculus and M. macedonicus —copy numbers ranged from 6 to 1810 per haploid genome. The repeat cluster is cytogenetically visible as a fine C-band in M. macedonicus and as a C-band positive Homogeneously Staining Region (HSR) in several populations of M. m. domesticus and M. m. musculus . When cytogenetically visible, the clusters contained from 179 to 1810 repeats. Intragenomic restriction fragment length polymorphisms (RFLPs), which reflect sequence variation among different copies of the long-range repeat family, increased with higher copy numbers. The high similarity of the RFLP pattern among genomes with C-band positive Regions in Chr 1 of M. m. musculus, M. m. domesticus , and M. macedonicus points to a close evolutionary relationship of their Chr 1 repeat families.
Andrew S Belmont - One of the best experts on this subject based on the ideXlab platform.
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interphase cell cycle dynamics of a late replicating heterochromatic Homogeneously Staining Region precise choreography of condensation decondensation and nuclear positioning
Journal of Cell Biology, 1998Co-Authors: Gang Li, Gail Sudlow, Andrew S BelmontAbstract:Recently we described a new method for in situ localization of specific DNA sequences, based on lac operator/repressor recognition (Robinett, C.C., A. Straight, G. Li, C. Willhelm, G. Sudlow, A. Murray, and A.S. Belmont. 1996. J. Cell Biol. 135:1685–1700). We have applied this methodology to visualize the cell cycle dynamics of an ∼90 Mbp, late-replicating, heterochromatic Homogeneously Staining Region (HSR) in CHO cells, combining immunoStaining with direct in vivo observations. Between anaphase and early G1, the HSR extends approximately twofold to a linear, ∼0.3-μm-diam chromatid, and then recondenses to a compact mass adjacent to the nuclear envelope. No further changes in HSR conformation or position are seen through mid-S phase. However, HSR DNA replication is preceded by a decondensation and movement of the HSR into the nuclear interior 4–6 h into S phase. During DNA replication the HSR resolves into linear chromatids and then recondenses into a compact mass; this is followed by a third extension of the HSR during G2/ prophase. Surprisingly, compaction of the HSR is extremely high at all stages of interphase. Preliminary ultrastructural analysis of the HSR suggests at least three levels of large-scale chromatin organization above the 30-nm fiber.
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Interphase cell cycle dynamics of a late-replicating, heterochromatic Homogeneously Staining Region : Precise choreography of condensation/decondensation and nuclear positioning
Journal of Cell Biology, 1998Co-Authors: Gang Li, Gail Sudlow, Andrew S BelmontAbstract:Recently we described a new method for in situ localization of specific DNA sequences, based on lac operator/repressor recognition (Robinett, C.C., A. Straight, G. Li, C. Willhelm, G. Sudlow, A. Murray, and A.S. Belmont. 1996. J. Cell Biol. 135:1685–1700). We have applied this methodology to visualize the cell cycle dynamics of an ∼90 Mbp, late-replicating, heterochromatic Homogeneously Staining Region (HSR) in CHO cells, combining immunoStaining with direct in vivo observations. Between anaphase and early G1, the HSR extends approximately twofold to a linear, ∼0.3-μm-diam chromatid, and then recondenses to a compact mass adjacent to the nuclear envelope. No further changes in HSR conformation or position are seen through mid-S phase. However, HSR DNA replication is preceded by a decondensation and movement of the HSR into the nuclear interior 4–6 h into S phase. During DNA replication the HSR resolves into linear chromatids and then recondenses into a compact mass; this is followed by a third extension of the HSR during G2/ prophase. Surprisingly, compaction of the HSR is extremely high at all stages of interphase. Preliminary ultrastructural analysis of the HSR suggests at least three levels of large-scale chromatin organization above the 30-nm fiber.