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VersKiK: Study protocol of an observational registry-based study on the current state of follow-up care and adherence to follow-up guidelines after cancer in childhood or adolescence. Cancer Epidemiol 2023; 87:102469. [PMID: 37806118 DOI: 10.1016/j.canep.2023.102469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 09/14/2023] [Accepted: 10/02/2023] [Indexed: 10/10/2023]
Abstract
BACKGROUND This article describes the study design of the quantitative part of the VersKiK study, The primary objectives of this study are to examine the occurrence of late effects in survivors of childhood or adolescent cancer (module 1), investigate health-related vulnerabilities and medical service utilization within this survivor group (modules 1 and 3), and assess the alignment between documented follow-up care for cardiological and audiological late effects with guideline recommendations, along with evaluating the extent of adherence among paediatric cancer survivors (module 3). METHODS This is a non-interventional retrospective observational cohort study. It is based on stochastically linked insurance claims data from approximately 150,000 statutory insured persons with information concerning around 25,000-30,000 cancer survivors recorded in the German Childhood Cancer Register (GCCR). To explore adherence to selected follow-up guidelines, intention to treat treatment data from clinical study groups for particular diagnostic entities will be additionally included. DISCUSSION The growing group of survivors after cancer in childhood and adolescence is representing a special population with an increasing demand for life-long healthcare services through relative high probability of late effects. Currently, there is a limited evidence in Germany on utilization of corresponding medical services and adherence to follow-up guidelines. With this study design, we are aiming to address these gaps and, consequently, suggest improvements to existing follow-up guidelines and follow-up care provision in Germany.
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Long-term care, care needs and wellbeing of individuals after cancer in childhood or adolescence (VersKiK): study protocol of a large scale multi-methods non-interventional study. BMC Health Serv Res 2022; 22:1176. [PMID: 36127717 PMCID: PMC9487026 DOI: 10.1186/s12913-022-08549-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 09/08/2022] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND It has been shown previously that a relevant proportion of childhood cancer survivors suffers from late effects, which are often directly related to the cancer itself or its therapy, resulting in particular follow-up needs, additionally burdening healthcare systems. Being diagnosed with cancer at a vulnerable stage of development, this group of cancer survivors is at comparatively higher risk of relapse or subsequent cancer. Although national and international follow-up guidelines based on treatment modalities have been developed, their implementation seems to leave room for improvement. Additionally, they lack a sufficient consideration of the survivors' psychosocial needs, affecting their adherence to them. The aim of the VersKiK study is to provide representative information on late effects in childhood and adolescence cancer survivors in Germany. The main research objectives are: (1) to describe the state of follow-up care among survivors after a cancer diagnosis in childhood or adolescence; (2) to quantify the occurrence of late effects among this group of survivors; (3) to examine the adherence to selected audiological and cardiological follow-up guidelines and to identify factors affecting it; (4) to explore actual follow-up needs of paediatric cancer survivors; (5) to review selected follow-up guidelines with the aim to improve and expand them. METHODS VersKiK is designed as a mixed-methods non-interventional study. We will use claims data from statutory health insurance companies in combination with individually linked population-based registry data from the German Childhood Cancer Registry (GCCR). This data base will permit us to quantify diagnoses and procedures in comparison to the general population as well as the adherence to existing follow-up guidelines. Additional information will be obtained through interviews with childhood and adolescence cancer survivors and their informal caregivers, as well as in focus groups with healthcare professionals. DISCUSSION The present study aims to research the actual needs of individuals after cancer diagnosis and treatment in childhood or adolescence - physical, psychological and organisational - in order to improve existing follow-up guidelines. These improvements might further positively affect not only actual care provided to paediatric cancer survivors, but also benefit healthcare systems in general while decreasing consequent medical visits in this group of patients. TRIAL REGISTRATION Registered at German Clinical Trial Register (ID: DRKS00025960 and DRKS00026092).
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Zusammenführung von Daten aus dem Deutschen
Kinderkrebsregister (DKKR) mit Routinedaten aus gesetzlichen Krankenkassen:
methodische Aspekte aus der VersKiK-Studie. DAS GESUNDHEITSWESEN 2022. [DOI: 10.1055/s-0042-1753627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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[Latent Tuberculosis Infection (LTBI) among Medical Personnel after Foreign Assignments]. Pneumologie 2020; 74:429-435. [PMID: 32259872 DOI: 10.1055/a-1127-9537] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
INTRODUCTION Every year, medical personnel are sent abroad via relief organisations in order to provide humanitarian aid. The areas they are sent to are often countries with a high incidence of tuberculosis. The prevalence of latent tuberculosis infections (LTBI) and associated risk factors among returnees in Germany have not yet been systematically investigated. METHODS In a cross-sectional study (N = 95), medical personnel in Germany who had completed at least one foreign assignment were tested for LTBI with the Interferon-Gamma Release Assay in order to examine the LTBI prevalence among them. Relevant risk factors were assessed using a questionnaire. Statistical evaluation was carried out using cross-tables and multiple logistic regression. RESULTS The LTBI prevalence in our sample was 12.63 %, 95 %CI (7.70 %; 23.89 %). The odds of LTBI increased with age (OR = 1.06, 95 %CI [1.01; 1.12], p-value = 0.021, per one life-year) and length of stay abroad (OR = 1.11, 95 %CI [1.03; 1.21], p-value = 0.009, per month). DISCUSSION The study showed a higher LTBI prevalence among returnees after assignments abroad than among medical personnel in Germany after TB contact who had been investigated in previous studies. In order to be able to detect LTBI infections acquired abroad, routine testing before and after an assignment abroad seems to be necessary.
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Treatment trial with recombinant human erythropoietin in children with congenital hypoplastic anemia. CONTRIBUTIONS TO NEPHROLOGY 2015; 88:276-80; discussion 281. [PMID: 2040190 DOI: 10.1159/000419537] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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Discussion of correlation patterns based on automated analysis of VCG and constitutional data. Adv Cardiol 2015; 21:296-9. [PMID: 619555 DOI: 10.1159/000400467] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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033. IMPORTIN α2 MEDIATES SUBNUCLEAR TARGETING OF THE CAJAL BODY COMPONENT COILIN; A KEY ROLE IN SPERMATOGENESIS? Reprod Fertil Dev 2010. [DOI: 10.1071/srb10abs033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Spermatogenesis, the progressive maturation of immature germ cells to form spermatozoa, requires nucleocytoplasmic shuttling of nuclear factors to implement changes in gene transcription, as well as the storage and alternative splicing of mRNA transcripts in the nucleus that is vital for fertility. The key cellular mediators of nuclear entry are members of the importin (IMP) superfamily, of which the five different IMPα proteins in mouse testis are expressed dynamically throughout spermatogenesis, consistent with roles in transporting distinct, specific cargoes critical to gamete maturation. We identified the central Cajal body (CB) component Coilin as a specific testicular binding partner of IMPα2 in a yeast 2-hybrid screen and confirmed this interaction by coimmunoprecipitation from testis lysates. CBs are small nuclear inclusions that can associate with histone genes and facilitate histone pre-mRNA processing by recruiting RNA processing factors; intriguingly, expression of IMPα2 but not other IMPαs can regulate the number and size of CBs, as shown in cell culture experiments. Immunohistochemical analysis revealed that Coilin is predominantly in spermatocytes and in round and elongating spermatids in the rodent testis. The physiological importance of its role is indicated by the fact that Coilin knockout mice have reduced fertility, smaller testes and aberrant spermatogenesis. Our future work will focus on the testicular functions of Coilin and IMPα2 during spermatogenesis, and their roles in coordinating the pre-assembly, storage and targeting of transcription complexes to RNA processing machinery in the nucleus.
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Abstract
Ran is a multi-functional small GTPase of the Ras super-family involved in nucleocytoplasmic transport, mitotic spindle assembly, cell cycle control and nuclear envelope (NE) formation. Its roles are accomplished by the asymmetric distribution of its GTP- and GDP-bound forms, enabled by the specific localization of Ran accessory proteins, the Ran GTPase-activating protein RanGAP and the nucleotide exchange factor RCC1. Mammalian RanGAP1 is targeted to the NE during interphase and to the spindle and kinetochores during mitosis via a SUMOylated C-terminal domain and interaction with the nucleoporin Nup358/RanBP2. Arabidopsis RanGAP1 (AtRanGAP1) lacks the SUMOylated C-terminal domain of vertebrate RanGAP, but contains a plant-specific N-terminal domain (WPP domain), which is necessary and sufficient for its targeting to the NE in interphase. AtRanGAP1 has a mitotic trafficking pattern uniquely different from that of vertebrate RanGAP, which includes targeting to the outward-growing rim of the cell plate. The WPP domain is necessary and sufficient for this targeting. Now, a novel family of plant-specific, nuclear pore-associated proteins has been identified in Arabidopsis, which is essential for anchoring RanGAP to the Arabidopsis nuclear envelope at the root meristem. This suggests that RanGAP anchoring to the nuclear pore has been solved in two fundamentally different ways in animals and plants. These findings support a separate evolution of RanGAP targeting mechanisms in different kingdoms, possibly related to different functional geometries of the Ran gradient in animal and higher plant cell division.
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131 Gene expression profile in irradiated and non-irradiated lymphoblastoid cell lines differing in P53 status. Radiother Oncol 2006. [DOI: 10.1016/s0167-8140(06)80610-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Scaffolds, levers, rods and springs: diverse cellular functions of long coiled-coil proteins. Cell Mol Life Sci 2004; 61:1996-2009. [PMID: 15316650 DOI: 10.1007/s00018-004-4039-6] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Long alpha-helical coiled-coil proteins are involved in a variety of organizational and regulatory processes in eukaryotic cells. They provide cables and networks in the cyto- and nucleoskeleton, molecular scaffolds that organize membrane systems, motors, levers, rotating arms and possibly springs. A growing number of human diseases are found to be caused by mutations in long coiled-coil proteins. This review summarizes our current understanding of the multifaceted group of long coiled-coil proteins in the cytoskeleton, nucleus, Golgi and cell division apparatus. The biophysical features of coiled-coil domains provide first clues toward their contribution to the diverse protein functions and promise potential future applications in the area of nanotechnology. Combining the power of fully sequenced genomes and structure prediction algorithms, it is now possible to comprehensively summarize and compare the complete inventory of coiled-coil proteins of different organisms.
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A domain unique to plant RanGAP is responsible for its targeting to the plant nuclear rim. Proc Natl Acad Sci U S A 2001; 98:15377-82. [PMID: 11752475 PMCID: PMC65037 DOI: 10.1073/pnas.261459698] [Citation(s) in RCA: 122] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ran is a small signaling GTPase that is involved in nucleocytoplasmic transport. Two additional functions of animal Ran in the formation of spindle asters and the reassembly of the nuclear envelope in mitotic cells have been recently reported. In contrast to Ras or Rho, Ran is not associated with membranes. Instead, the spatial sequestering of its accessory proteins, the Ran GTPase-activating protein RanGAP and the nucleotide exchange factor RCC1, appears to define the local concentration of RanGTP vs. RanGDP involved in signaling. Mammalian RanGAP is bound to the nuclear pore by a mechanism involving the attachment of small ubiquitin-related modifier protein (SUMO) to its C terminus and the subsequent binding of the SUMOylated domain to the nucleoporin Nup358. Here we show that plant RanGAP utilizes a different mechanism for nuclear envelope association, involving a novel targeting domain that appears to be unique to plants. The N-terminal WPP domain is highly conserved among plant RanGAPs and the small, plant-specific nuclear envelope-associated protein MAF1, but not present in yeast or animal RanGAP. Confocal laser scanning microscopy of green fluorescent protein (GFP) fusion proteins showed that it is necessary for RanGAP targeting and sufficient to target the heterologous protein GFP to the plant nuclear rim. The highly conserved tryptophan and proline residues of the WPP motif are necessary for its function. The 110-aa WPP domain is the first nuclear-envelope targeting domain identified in plants. Its fundamental difference to its mammalian counterpart implies that different mechanisms have evolved in plants and animals to anchor RanGAP at the nuclear surface.
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Abstract
This review summarizes our present knowledge about the composition and function of the plant nuclear envelope. Compared with animals or yeast, our molecular knowledge of the nuclear envelope in higher plants is in its infancy. However, there are fundamental differences between plants and animals in the structure and function of the nuclear envelope. This review will compare and contrast these differences for nuclear pore complexes, nuclear transport, inner nuclear envelope proteins and the role of the nuclear envelope during mitosis. In some cases, seemingly 'novel' aspects of plant nuclear envelope function may provide new insight into the animal cell nucleus.
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Characterisation and high-resolution distribution of a matrix attachment region-binding protein (MFP1) in proliferating cells of onion. PLANTA 2001; 212:535-546. [PMID: 11525510 DOI: 10.1007/s004250000446] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The first matrix attachment region (MAR)-binding protein sequenced in plants, MFP1, has been characterised in two dicot species. Based on their antigenic relationship, we report here the conservation of MFP1-like proteins in proliferating root cells of onion (Allium cepa L). Two MFP1-like proteins with different molecular masses and solubilities were detected. The most abundant was a 90-kDa basic protein, presenting several separate spots in two-dimensional blots. The MFP1 was partially soluble and, similar to the proliferating cell nuclear antigen (PCNA)-labelled replication factories in the nucleus and nuclear matrix, was localised at discrete foci as detected by confocal microscopy. High-resolution immunolocalisation of MFP1 by electron microscopy identified the foci as nuclear structures, some of them containing PCNA, which are ultrastructurally similar to the replication factories described in animal cells. Our data provide the first report on MFP1-like proteins in the Alliaceae. In addition, we present evidence of the presence of AcMFP1 in the putative replication factories.
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A novel link between ran signal transduction and nuclear envelope proteins in plants. PLANT PHYSIOLOGY 2000; 124:1507-10. [PMID: 11115866 PMCID: PMC1539304 DOI: 10.1104/pp.124.4.1507] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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Disruption of the gene encoding the ubiquitin-conjugating enzyme UbcM4 has no effect on proliferation and in vitro differentiation of mouse embryonic stem cells. BIOCHIMICA ET BIOPHYSICA ACTA 2000; 1494:75-82. [PMID: 11072070 DOI: 10.1016/s0167-4781(00)00221-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The ubiquitin-conjugating enzyme UbcM4, which is identical to the human enzyme UbcH7, was previously shown to be essential for normal mouse development. In order to study the possible role of UbcM4 for cell proliferation and in vitro differentiation, we here describe the establishment and characterization of fibroblast and embryonic stem cell lines with partial or complete inactivation of the UbcM4 gene. ES cell lines in which both alleles of the gene were inactivated by targeted mutagenesis showed no differences in growth rates, cell cycle progression and in vitro differentiation when compared to wild-type ES cells. Fibroblast cell lines with a partially inactivated UbcM4 gene were derived from embryos of the previously described A6 mouse mutant, where retrovirus integration has resulted in a recessive lethal mutation. As in the mutant embryos, steady levels of RNA and protein in the cell lines were reduced by about 70%. The mutant cell lines showed no differences in immortalization kinetics, growth rates and cell cycle progression when compared to wild-type fibroblasts. Taken together, our results strongly suggest that UbcM4-mediated ubiquitination and degradation are not necessary for proteins involved in the maintenance and growth of cells.
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Conservation of matrix attachment region-binding filament-like protein 1 among higher plants. PLANT PHYSIOLOGY 2000; 122:225-34. [PMID: 10631266 PMCID: PMC58861 DOI: 10.1104/pp.122.1.225] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/1999] [Accepted: 10/11/1999] [Indexed: 05/21/2023]
Abstract
The interaction of chromatin with the nuclear matrix via matrix attachment regions (MARs) on the DNA is considered to be of fundamental importance for higher-order chromatin organization and the regulation of gene expression. We have previously isolated a novel nuclear matrix-localized protein (MFP1) from tomato (Lycopersicon esculentum) that preferentially binds to MAR DNA. Tomato MFP1 has a predicted filament-protein-like structure and is associated with the nuclear envelope via an N-terminal targeting domain. Based on the antigenic relationship, we report here that MFP1 is conserved in a large number of dicot and monocot species. Several cDNAs were cloned from tobacco (Nicotiana tabacum) and shown to correspond to two tobacco MFP1 genes. Comparison of the primary and predicted secondary structures of MFP1 from tomato, tobacco, and Arabidopsis indicates a high degree of conservation of the N-terminal targeting domain, the overall putative coiled-coil structure of the protein, and the C-terminal DNA-binding domain. In addition, we show that tobacco MFP1 is regulated in an organ-specific and developmental fashion, and that this regulation occurs at the level of transcription or RNA stability.
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The tomato I-box binding factor LeMYBI is a member of a novel class of myb-like proteins. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1999; 20:641-652. [PMID: 10652136 DOI: 10.1046/j.1365-313x.1999.00638.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The RBCS3A gene of tomato belongs to a small gene family consisting of five members. Although the RBCS1, RBCS2 and RBCS3A promoters contain closely related cis regulatory sequences, the expression patterns of the genes are different. Whereas the RBCS1 and RBCS2 genes are expressed in both leaves and young fruit, the RBCS3A promoter is highly active in leaves, but not in young fruit. This lack of transcription could be due to a mutation in the RBCS3A promoter creating the so-called F-box, a protein binding site located between the activating cis elements, the I-box and G-box. In order to identify proteins that bind to the RBCS3A I-box/F-box region, the yeast one-hybrid system was used. One clone, LeMYBI was isolated which contains strong similarity to plant myb transcription factors. The encoded LeMYBI protein is at least 188 amino acids in length and contains two myb-like domains located at the amino terminus and close to the carboxy terminus, separated by a negatively charged domain. The protein contains a SHAQKYF amino acid signature motif in the second myb-like repeat, which is highly conserved in a number of recently identified plant myb-related genes, thus defining a new class of plant DNA-binding proteins. LeMYBI binds specifically to the I-box sequence of the RBCS1, RBCS2 and RBCS3A promoters, therefore representing the first cloned I-box binding factor. LeMYBI acts as a transcriptional activator in yeast and plants, and binds to the I-box with a DNA-binding domain located in the carboxyterminal domain.
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MESH Headings
- Amino Acid Sequence
- Base Sequence
- Binding Sites/genetics
- Cloning, Molecular
- DNA, Complementary/genetics
- DNA, Plant/genetics
- DNA, Plant/metabolism
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation, Plant
- Genes, Plant
- Solanum lycopersicum/genetics
- Solanum lycopersicum/metabolism
- Molecular Sequence Data
- Multigene Family
- Plant Proteins/genetics
- Plant Proteins/metabolism
- Promoter Regions, Genetic
- Proto-Oncogene Proteins c-myb
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- RNA, Plant/genetics
- RNA, Plant/metabolism
- Saccharomyces cerevisiae/genetics
- Sequence Homology, Amino Acid
- Transcription Factors/genetics
- Transcription Factors/metabolism
- Transcriptional Activation
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MAF1, a novel plant protein interacting with matrix attachment region binding protein MFP1, is located at the nuclear envelope. THE PLANT CELL 1999; 11:1755-68. [PMID: 10488241 PMCID: PMC144308 DOI: 10.1105/tpc.11.9.1755] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The interaction of chromatin with the nuclear matrix via matrix attachment region (MAR) DNA is considered to be of fundamental importance for chromatin organization in all eukaryotic cells. MAR binding filament-like protein 1 (MFP1) from tomato is a novel plant protein that specifically binds to MAR DNA. Its filament protein-like structure makes it a likely candidate for a structural component of the nuclear matrix. MFP1 is located at nuclear matrix-associated, specklelike structures at the nuclear envelope. Here, we report the identification of a novel protein that specifically interacts with MFP1 in yeast two-hybrid and in vitro binding assays. MFP1 associated factor 1 (MAF1) is a small, soluble, serine/threonine-rich protein that is ubiquitously expressed and has no similarity to known proteins. MAF1, like MFP1, is located at the nuclear periphery and is a component of the nuclear matrix. These data suggest that MFP1 and MAF1 are in vivo interaction partners and that both proteins are components of a nuclear substructure, previously undescribed in plants, that connects the nuclear envelope and the internal nuclear matrix.
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Reduction of G-box binding factor DNA binding activity, but not G-box binding factor abundance, causes the downregulation of RBCS2 expression during early tomato fruit development. FEBS Lett 1999; 454:95-9. [PMID: 10413103 DOI: 10.1016/s0014-5793(99)00784-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The downregulation of RBCS2 promoter activity during tomato fruit development has been investigated by transient gene expression. A major drop in promoter activity occurs between 5 and 25 mm fruit diameter, corresponding to the late cell division to early cell enlargement phase. This drop is abolished by a mutation of the single G-box element necessary for high RBCS2 promoter activity in young tomato fruit. The G-box binding activity of fruit nuclear and total protein extracts drops concomitantly with the reduction of RBCS2 promoter activity while G-box binding factor expression is not affected. The data indicate that the developmental signal that downregulates the RBCS2 promoter acts on the regulation of DNA binding activity of constitutively expressed G-box binding factors.
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Matrix attachment region binding protein MFP1 is localized in discrete domains at the nuclear envelope. THE PLANT CELL 1999; 11:1117-28. [PMID: 10368182 PMCID: PMC144256 DOI: 10.1105/tpc.11.6.1117] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Recently, it has been suggested that nuclear processes, such as replication, transcription, and splicing, are spatially organized and associated with a nuclear framework called the nuclear matrix, a structure of unknown molecular composition. It has been shown that chromatin is attached to the nuclear matrix via specific DNA fragments called matrix attachment regions (MARs). We have begun to dissect the plant nuclear matrix by isolating a DNA binding protein with specific affinity for MARs. Here, it is shown that MAR binding filament-like protein 1 (MFP1) is associated with specklelike structures at the nuclear periphery that are part of isolated nuclei and the nuclear matrix. A predicted N-terminal transmembrane domain is necessary for the specific targeting of MFP1 to the speckles, indicating an association with the nuclear envelope-endoplasmic reticulum continuum. In addition, it is shown that a marker protein for plant microtubule organizing centers, which has been shown to be localized on the outside of the plant nuclear envelope, is also part of the nuclear matrix. These findings indicate a close and previously undescribed connection in plants between the nuclear envelope and the internal nuclear matrix, and they suggest a function for MFP1 in attaching chromatin to specific sites at the nuclear periphery.
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The tomato RBCS3A promoter requires integration into the chromatin for correct organ-specific regulation. FEBS Lett 1997; 415:91-5. [PMID: 9326376 DOI: 10.1016/s0014-5793(97)01102-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
In tomato, the RBCS1, RBCS2 and RBCS3A genes, encoding the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase, are expressed in leaves and light-grown seedlings, but only RBCS1 and RBCS2 are expressed in developing tomato fruits. The activities of the three promoters have been compared in transgenic plants and after transient transformation. Fruit-specific repression of the RBCS3A promoter was observed in transgenic plants, but not after ballistic transient transformation, indicating that chromatin integration is necessary for its correct organ-specific regulation. In addition, matrix attachment regions have been identified in the RBCS1, RBCS2 and RBCS3A promoters. This is the second case in plants of absence of correct regulation of a plasmid-borne plant promoter and correlating potential nuclear matrix attachment of the gene.
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Improved ballistic transient transformation conditions for tomato fruit allow identification of organ-specific contributions of I-box and G-box to the RBCS2 promoter activity. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 1997; 12:463-469. [PMID: 9301095 DOI: 10.1046/j.1365-313x.1997.12020463.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
An improved protocol for the ballistic transient transformation of developing tomato (Lycopersicon esculentum) fruits is reported, which allows high-resolution cis-analysis of fruit-specific transcriptional activation. The tomato RBCS2 promoter fused to the firefly luciferase gene was used as a model system for this study. Osmotic treatment of fruit slices before, during and after particle bombardment, together with the optimization of bombardment conditions, resulted in a 100-fold increase in RBCS2 promoter-driven transient luciferase expression compared with previously reported protocols. Under these conditions, the transformed RBCS2 promoter was shown to be properly regulated in a developmental fashion. A cis-analysis of the RBCS2 promoter was performed. A 37 bp domain is required for high-level RBCS2 promoter activity both in leaves and young fruits. Two conserved sequence elements within this domain, an I-box element (GATAAG) and a G-box element (CACGTG), are necessary for its activity in leaves. In contrast, in young fruits, the G-box is the single dominant cis-acting element. These findings are discussed with respect to the proposed functions of G-box and I-box binding factors in regulating plant genes in different organs.
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MFP1, a novel plant filament-like protein with affinity for matrix attachment region DNA. THE PLANT CELL 1996; 8:2105-15. [PMID: 8953774 PMCID: PMC161338 DOI: 10.1105/tpc.8.11.2105] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
The interaction of chromatin with the nuclear matrix via matrix attachment regions (MARs) on the DNA is considered to be of fundamental importance for higher order chromatin organization and regulation of gene expression. Here, we report a novel nuclear matrix-localized MAR DNA binding protein, designated MAR binding filament-like protein 1 (MFP1), from tomato. In contrast to the few animal MAR DNA binding proteins thus far identified, MFP1 contains a predicted N-terminal transmembrane domain and a long filament-like alpha-helical domain that is similar to diverse nuclear and cytoplasmic filament proteins from animals and yeast. DNA binding assays established that MFP1 can discriminate between animal and plant MAR DNAs and non-MAR DNA fragments of similar size and AT content. Deletion mutants of MFP1 revealed a novel, discrete DNA binding domain near the C terminus of the protein. MFP1 is an in vitro substrate for casein kinase II, a nuclear matrix-associated protein kinase. Its structure, MAR DNA binding activity, and nuclear matrix localization suggest that MFP1 is likely to participate in nuclear architecture by connecting chromatin with the nuclear matrix and potentially with the nuclear envelope.
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Subunit structure and organization of the genes of the A1A0 ATPase from the Archaeon Methanosarcina mazei Gö1. J Biol Chem 1996; 271:18843-52. [PMID: 8702544 DOI: 10.1074/jbc.271.31.18843] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The proton-translocating A1A0 ATP synthase/hydrolase of Methanosarcina mazei Gö1 was purified and shown to consist of six subunits of molecular masses of 65, 49, 40, 36, 25, and 7 kDa. Electron microscopy revealed that this enzyme is organized in two domains, the hydrophilic A1 and the hydrophobic A0 domain, which are connected by a stalk. Genes coding for seven hydrophilic subunits were cloned and sequenced. From these data it is evident that the 65-, 49-, 40- and 25-kDa subunits are encoded by ahaA, ahaB, ahaC, and ahaD, respectively; they are part of the A1 domain or the stalk. In addition there are three more genes, ahaE, ahaF, and ahaG, encoding hydrophilic subunits, which were apparently lost during the purification of the protein. The A0 domain consists of at least the 7-kDa proteolipid and the 36-kDa subunit for which the genes have not yet been found. In summary, it is proposed that the A1A0 ATPase of Methanosarcina mazei Gö1 contains at least nine subunits, of which seven are located in A1 and/or the stalk and two in A0.
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Organ-specific differential regulation of a promoter subfamily for the ribulose-1,5-bisphosphate carboxylase/oxygenase small subunit genes in tomato. PLANT PHYSIOLOGY 1995; 107:1105-18. [PMID: 7770521 PMCID: PMC157243 DOI: 10.1104/pp.107.4.1105] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The tomato (Lycopersicon esculentum) gene family for the small subunit of ribulose-1,5-bisphosphate carboxylase/oxygenase (RBCS) has been investigated to determine the role of promoter regions and DNA-protein interactions in the differential organ-specific transcription of individual genes. Transgenic plants expressing RBCS-promoter-beta-glucuronidase fusion genes have confirmed that promoter fragments ranging from 0.6 to 3.0 kb of the RBCS1, RBCS2, and RBCS3A genes were sufficient to confer the temporal, organ-specific, and differential expression pattern observed for the endogenous genes. The individual temporal and organ-specific beta-glucuronidase enzyme activities closely reflect the qualitative and quantitative transcription activities of the respective RBCS genes, including the strongly reduced activity of RBCS3A (L.A. Wanner, W. Gruissem [1991] Plant Cell 3: 1289-1303). In particular, tissue-specific activity of all three promoters is similar in developing fruit, with high activity in the locular tissue and extremely reduced activity in the pericarp. This specific pattern of gene activity was further substantiated by in situ analysis of RBCS mRNA levels. Together, the data suggest an interesting correlation between RBCS gene activity and sink strength in different fruit tissues. DNA-protein interaction studies have revealed a novel fruit-specific DNA-binding protein called FBF that specifically interacts with a sequence element directly upstream of the G-box in the RBCS3A promoter. FBF binding thus correlates with the reduced activity of this promoter in developing tomato fruit, rendering it a candidate for a fruit-specific negative regulator of transcription in tomato.
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MESH Headings
- Base Sequence
- Binding Sites/genetics
- DNA, Plant/genetics
- DNA, Plant/metabolism
- DNA-Binding Proteins/metabolism
- Gene Expression Regulation, Enzymologic
- Gene Expression Regulation, Plant
- Genes, Plant
- Glucuronidase/genetics
- Solanum lycopersicum/enzymology
- Solanum lycopersicum/genetics
- Solanum lycopersicum/growth & development
- Molecular Sequence Data
- Multigene Family
- Organ Specificity
- Plant Proteins/metabolism
- Plants, Genetically Modified
- Promoter Regions, Genetic
- RNA, Messenger/genetics
- RNA, Messenger/metabolism
- Ribulose-Bisphosphate Carboxylase/genetics
- Transformation, Genetic
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Plant homeodomain protein involved in transcriptional regulation of a pathogen defense-related gene. THE PLANT CELL 1994; 6:695-708. [PMID: 7913642 PMCID: PMC160469 DOI: 10.1105/tpc.6.5.695] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Transcription of the parsley pr2 gene, encoding pathogenesis-related protein 2 (PR2), is rapidly stimulated by fungal or bacterial elicitors. Previous work has revealed a 125-bp region within the pr2 promoter; this region encompasses all important cis-regulatory elements required for fungal elicitor-mediated expression. We now report the identification of a functionally relevant 11-bp DNA motif (CTAATTGTTTA) contained within this region; it specifically binds to factors present in both parsley and Arabidopsis nuclear protein extracts. From both plant species, full-length cDNA clones were isolated that encode proteins with high affinity fo this DNA motif. The proteins from both species contain stretches of 61 amino acids that are characteristic of homeodomain (HD) proteins. Binding studies and use of a polyclonal antiserum raised against a fusion polypeptide of glutathione S-transferase with the HD portion of the parsley protein indicated that the 11-bp DNA motif is a potential in vivo target site and that the HD protein is contained within the observed complex formed between the DNA motif and nuclear protein extracts. Transient expression studies using the authentic and a mutated target site suggested a functional role of the HD-DNA interaction in the regulation of the pr2 gene expression.
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Novel conserved sequence motifs in plant G-box binding proteins and implications for interactive domains. Nucleic Acids Res 1994; 22:470-8. [PMID: 8127687 PMCID: PMC523606 DOI: 10.1093/nar/22.3.470] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The G-box is a cis-acting DNA sequence present in several plant promoters that are regulated by diverse signals such as UV irradiation, anaerobiosis, abscissic acid and light. Several basic/leucine zipper (bZIP) proteins from different plant species have been identified as high affinity G-box binding proteins. Although their capability to enhance transcription has been demonstrated, their precise function in transcriptional activation is still unknown. We have isolated three cDNAs from young tomato fruit that encode bZIP G-box binding proteins (GBF4, GBF9 and GBF12). They bind to the G-box sequence in the tomato rbcS1, rbcS2 and rbcS3A promoters. GBF9 binding resulted in a DNase I footprint identical to that obtained with tomato nuclear extract and different from the DNase I protection obtained with GBF4 and GBF12. The mRNAs of all three GBFs were most abundant in tomato fruit and seeds, moderately abundant in root and least abundant in leaves. Protein sequences outside of the bZIP domains were compared with the known GBFs from other plants and seven conserved motifs of seven to 35 amino acids length have been identified. Based on the presence of these motifs, three classes of GBFs can be defined that are conserved among plant species. GBF9, the predominantly expressed tomato GBF, is the first member of its class isolated from dicot plants. Three conserved motifs from two of the classes are highly hydrophilic and are predicted to be exposed on the surface of the proteins. These motifs likely define novel interactive domains in the different classes of GBFs that could provide a new tool to determine how distinct regulatory signals are transmitted through GBFs to activate transcription.
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Elicitor-inducible and constitutive in vivo DNA footprints indicate novel cis-acting elements in the promoter of a parsley gene encoding pathogenesis-related protein 1. THE PLANT CELL 1991; 3:309-15. [PMID: 1840913 PMCID: PMC160001 DOI: 10.1105/tpc.3.3.309] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
The presence of three genes encoding pathogenesis-related protein 1 (PR1) in cultured parsley cells and the activation of all three genes by fungal elicitor are demonstrated. In vivo dimethyl sulfate footprinting was used to identify two putative sites of protein-DNA interaction in the promoter of one PR1 gene, located around positions -240 and -130 relative to the transcription start site. The TATA-distal footprint was elicitor dependent and appeared within 30 minutes of elicitor treatment, concomitant with the onset of PR1 transcription. The second footprint was observed irrespective of whether elicitor was present or absent. The two footprinted regions contain, in opposite orientation, nearly identical 11-base pair motifs that are unrelated to any known cis-acting element in elicitor-activated or pathogen-activated plant genes. The results demonstrate the usefulness of in vivo footprinting for the identification of cis-acting elements within promoters not accessible to other types of analysis.
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Abstract
We describe the nucleotide sequence and some structural characteristics of a single copy gene encoding pathogenesis-related protein 2 (PR2) in parsley (Petroselinum crispum). Transcriptional activation of this gene in cultured parsley cells treated with fungal elicitor leads to a rapid, large and transient accumulation of PR2 mRNA. The deduced PR2 protein belongs to a novel class of evolutionarily conserved polypeptides which are closely related to disease resistance in plants. Functional analysis of a series of truncated PR2 promoter fusions with the beta-glucuronidase reporter gene, using parsley protoplasts for transient expression studies, identified a 5' upstream element between positions -168 and -52 necessary for strong elicitor responsiveness. This small promoter fragment is active in conjunction with its own TATA box region as well as with the corresponding region from a heterologous promoter. The PR2 regulatory region exhibits no sequence similarity to any other elicitor-responsive promoter known to date.
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30
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Nitrosation of aspartic acid, aspartame, and glycine ethylester. Alkylation of 4-(p-nitrobenzyl)pyridine (NBP) in vitro and binding to DNA in the rat. Mutat Res 1990; 238:193-201. [PMID: 2342512 DOI: 10.1016/0165-1110(90)90011-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
In a colorimetric assay using 4-(p-nitrobenzyl)pyridine (NBP) as a nucleophilic scavenger of alkylating agents, the nitrosation and alkylation reactions were investigated for a number of amino acids and derivatives. The alkylating activity increased with the square of the nitrite concentration. The nitrosation rate constants for aspartic acid, aspartame, and glycine ethylester (= precursors C) were 0.08, 1.4 and less than or equal to 0.2, respectively, expressed in terms of the pH-dependent k2 rate constant of the equation dNOC/dt = k2.[C].[nitrite]2. The rates correlated inversely with the basicity of the amino group. The stability of the alkylating activity was astonishingly high, both in acid and at neutral pH. Half-lives of 500, 200, and 30 min were determined for aspartic acid (pH 3.5), aspartame (pH 2.5), and glycine ethylester (pH 2.5). Values of 60, 15, and 2 min, respectively, were found at pH 7. It is concluded that rearrangement of the primary N-nitroso product to the ultimate alkylating agent could be rate-limiting. The potential of nitrosated alpha-amino acids to bind to DNA in vivo was investigated by oral gavage of radiolabelled glycine ethylester to rats, followed immediately by sodium nitrite. DNA was isolated from stomach and liver and analysed for radioactivity and modified nucleotides. No indication of DNA adduct formation was obtained. Based on an estimation of the dose fraction converted from glycine ethylester to the nitroso product under the given experimental conditions, the maximum possible DNA-binding potency of nitroso glycine ethylester is about one order of magnitude below the methylating potency of N-nitrosomethylurea in rat stomach. The apparent discrepancy to the in vitro data could be due to efficient detoxification processes in mammalian cells.
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31
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Saturation mutagenesis of the Tn10-encoded tet operator O1. Identification of base-pairs involved in Tet repressor recognition. J Mol Biol 1988; 202:397-406. [PMID: 2845099 DOI: 10.1016/0022-2836(88)90273-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Saturation mutagenesis of Tn10-encoded tet operator O1 was performed by chemical synthesis of 30 sequence variants yielding all possible point mutations of an operator half side. Their effect on Tet repressor binding was scored by an in-vivo repressor titration system. Tet repressor affinities of selected operator mutants were further characterized in vitro by dissociation rate measurements. The O1 sequence spans 19 base-pairs. Out of these, all 18 palindromic base-pairs are involved in Tet repressor recognition. The central base-pair does not contribute to sequence-specific binding of Tet repressor. At position 1 a pyrimidine residue is sufficient for maximal affinity to the repressor. At positions 2, 3 and 4, each mutation reduces repressor binding at least tenfold. Mutations at positions 5, 6, 7, 8 and 9 result in less drastic reductions of Tet repressor binding. Differential effects of mutations at a given position are used to deduce the chemical functions contacted by Tet repressor. The T.A to A.T transversion at position 9 increases Tet repressor affinity slightly, while all other mutations decrease repressor binding. The increased affinity of the wild-type tet operator O2 compared to wild-type O1 results from the addition of two favorable transversions at positions +/- 9 and an unfavorable T.A to C.G transition at position -7. Deletion or palindromic doubling of the central base-pair of the O1 palindrome reveals that the wild-type spacing of both operator half sides is crucial for efficient Tet repressor binding.
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Differential regulation of the Tn10-encoded tetracycline resistance genes tetA and tetR by the tandem tet operators O1 and O2. EMBO J 1988; 7:567-72. [PMID: 2835235 PMCID: PMC454355 DOI: 10.1002/j.1460-2075.1988.tb02846.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The Tn10-encoded tet transcriptional control sequence consists of bidirectional, overlapping promoters which are superimposed by a tandem operator arrangement. Three mutations have been constructed by oligonucleotide-directed mutagenesis which reduce binding of Tet repressor to either one or both of the tandem tet operators 1000-fold as determined by DNAseI footprinting in vitro. The affinity of Tet repressor for mutant tet operators is not affected by the presence of an already occupied neighbouring wild-type operator, indicating little or no cooperativity. The regulation of the divergently oriented tet promoters PA and PR by the tet operators O1 and O2 and Tet repressor provided in trans is determined using transcriptional fusions of the promoters to lacZ and galK indicator genes located with different polarity on the same plasmid. The results demonstrate that expression of the resistance gene tetA is regulated by Tet repressor bound to either O1 or O2. Expression of the repressor gene tetR is only marginally reduced when Tet repressor is bound to O2. This result is discussed with respect to the double promoter structure found for PR. Occupation of O1 with Tet repressor turns off transcription from PR completely. The implications of these findings on the establishment of tetracycline resistance upon induction are discussed.
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33
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Dimensions of the 'endangered self' in anorexia nervosa. Empirical study based on comparison with normal controls. PSYCHOTHERAPY AND PSYCHOSOMATICS 1988; 50:72-80. [PMID: 3255980 DOI: 10.1159/000288103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
In addition to the diagnosis of symptoms we recently proposed the empirical analysis of psychodynamic levels; this paper aims at an empirical study of a third, and most essential, problem area: disturbances and/or regulatory processes of the self-system. Based on Deneke's newly developed questionnaire, 30 anorexia nervosa patients were examined, and then compared with 64 normal controls (female university students). A self-profile comprising 18 scales is used to graphically illustrate the disturbances. The primary deficits were found in the subscales of the 'endangered self' and the 'hypochondriac self', while the subscales of the 'classic narcissistic self' and the 'idealistic self' were found to be irrelevant. The significant self-system scales were then related to the symptomatology. The conclusion of the paper contains some therapy considerations.
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Clinical process studies on anxiety and aggressiveness affects in the inpatient therapy of anorexia nervosa. PSYCHOTHERAPY AND PSYCHOSOMATICS 1988; 50:125-33. [PMID: 3267823 DOI: 10.1159/000288110] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Under the assumption of affect defense (alexithymia), 20 anorexia nervosa patients being treated in the University Hospital of Hamburg-Eppendorf were examined with respect to their affects of anxiety and aggressivity by employing speech samples (three times a week)--according to Gottschalk-Gleser--and questionnaires (ANIS) during hospitalization and compared to 10 control patients from somatic clinics (orthopedics, surgery, gynecology). Particular attention was given to emotional responses toward events during the inpatient period. The most important result found was the distinct affectivity in the anorexia patients, which was partly stronger than that of the somatic control patients, so that judging from our anorexia nervosa sample the hypothesis of alexithymia will have to be renewed and requires a more differentiated discussion.
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Abstract
The effect of single base pair alterations of the Tn10 encoded tet operator on recognition of Tet repressor was studied in vivo using a repressor titration system and in vitro by dissociation rate determinations of the respective complexes. Both methods reveal that the two operators, O1 and O2, which are in a tandem arrangement in the wild type, are recognized with a two-fold different affinity when separated. Studies on synthetic operator sequences indicate that the Tet repressor binds with higher affinity to the non-palindromic O2 wildtype than to the respective palindromic sequences. The in vivo repressor titration system links the expression of lacZ to the affinity of tet operator to Tet repressor. It was used to isolate tet operator mutations with reduced affinity to the repressor. The in vivo and in vitro obtained results with these mutants agree quantitatively and indicate, that the GC base pairs at positions 2, 6, and 8 are involved in interaction with the Tet repressor. Their importance for recognition decreases in that order. Transitions at position 7 of the tet operator show smaller effects on recognition than transversions.
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36
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Control of expression of the Tn10-encoded tetracycline resistance genes. Equilibrium and kinetic investigation of the regulatory reactions. J Mol Biol 1983; 169:707-21. [PMID: 6313933 DOI: 10.1016/s0022-2836(83)80166-1] [Citation(s) in RCA: 97] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The transposon Tn10-encoded TET repressor controls the expression of tetracycline resistance as well as its own synthesis. The antibiotic tetracycline functions as an inducer for both genes, which are transcribed in divergent directions from a common start area. The interaction of the TET repressor with the regulatory sequence of the tetracycline resistance operon is investigated by equilibrium and kinetic methods. The wild-type control sequence contains two nearly identical operators separated by only ten base-pairs. A deletion mutant lacking one of the operators is constructed by controlled digestion with exonuclease Bal31. It serves to prove that the two TET operators are each occupied by a TET repressor dimer in the wild-type tet operon regulatory sequence. The association constants are approximately identical for both operators between 10(12) and 10(13) M-1 as derived from kinetic data. The half-life of the TET repressor--tet operator complex is 12 minutes when competed with tet operator DNA and two minutes when competed with the inducer tetracycline. The dissociation of the repressor--operator complex has no apparent activation enthalpy but has an activation entropy of -320 J/mol K, indicating the involvement of solvent or counterion condensation. The dissociation rate constant of the tetracycline--TET repressor complex depends strongly on temperature. The activation enthalpy is 160 kJ/mol, indicating extremely strong binding of the drug. This result is discussed with respect to the necessary sensitivity of a regulated resistance gene. The native structure of the TET repressor is a dimer, as demonstrated by molecular exclusion chromatography. The elution behavior of the TET repressor--tetracycline complex indicates clearly that the repressor--inducer complex remains a dimer. The results are discussed with respect to the regulatory functions of the components.
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37
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[Relationship between frequency components of phonocardiography, vectorcardiography parameters and anatomic data]. ZEITSCHRIFT FUR KARDIOLOGIE 1976; 65:882-9. [PMID: 997706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Regarding heart volume, fundamental frequency of the first and second part of first heart sound (SI), vectorcardiographic parameters and constitutional data, the formerly found strong correlation between fundamental frequency of the first part of SI and heart volume was re-established. Heart volume guess got even better utilizing certain VCG-parameters, whereas constitutional measurement data gave no further approach. Correlations between VCG-data and fundamental frequencies of both parts of SI are referred to.
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38
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[Interpretation of orthodontically treated by means of punched cards. 2. Data at the completion of treatment]. STOMATOLOGIE DER DDR 1975; 25:377-82. [PMID: 1058536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The authors analysed the key-word cards of 3245 terminated orthodontic cases. Statistical data were obtained about treatment results, therapeutical aids, duration of treatment and co-operation of the patients. These data give a survey on the achievements of the orthodontic practitioner, the choice of his methods and the utilization of his therapeutical aids. The authors could draw certain conclusions as to their own work in practice. Furthermore, they realized that the use of key-word cards permits to evaluate critically their achievements and to perform collective scientific studies.
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Ein Computerprogramm zur mathematischen Frequenzanalyse von Herztönen. Test an simulierten Herztönen und erste Ergebnisse frequenzanalytischer Auswertungen. BIOMED ENG-BIOMED TE 1974. [DOI: 10.1515/bmte.1974.19.s1.39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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40
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[Evaluation of orthodontic cases by means of punched cards. 1. Data at start of therapy]. DEUTSCHE STOMATOLOGIE 1973; 23:772-7. [PMID: 4588555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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