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Downregulation of Protein 4.1R impairs centrosome function,bipolar spindle organization and anaphase

Description: Centrosomes nucleate and organize interphase MTs and areinstrumental in the assembly of the mitotic bipolar spindle. Here wereport that two members of the multifunctional protein 4.1 family havedistinct distributions at centrosomes. Protein 4.1R localizes to maturecentrioles whereas 4.1G is a component of the pericentriolar matrixsurrounding centrioles. To selectively probe 4.1R function, we used RNAinterference-mediated depletion of 4.1R without decreasing 4.1Gexpression. 4.1R downregulation r… more
Date: March 17, 2006
Creator: Spence, Jeffrey R.; Go, Minjoung M.; Bahmanyar, S.; Barth,A.I.M. & Krauss, Sharon Wald
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Stem-loop structures of the repetitive DNA sequences located at human centromeres

Description: The presence of the highly conserved repetitive DNA sequences in the human centromeres argues for a special role of these sequences in their biological functions - most likely achieved by the formation of unusual structures. This prompted us to carry out quantitative one- and two-dimensional nuclear magnetic resonance (lD/2D NMR) spectroscopy to determine the structural properties of the human centromeric repeats, d(AATGG){sub n.d}(CCATT){sub n}. The studies on centromeric DNAs reveal that the … more
Date: September 1, 1993
Creator: Gupta, G.; Garcia, A. E.; Ratliff, R.; Moyzis, R. K.; Catasti, P.; Hong, Lin et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Attenuation of G{sub 2} cell cycle checkpoint control in human tumor cells is associated with increased frequencies of unrejoined chromosome breaks but not increased cytotoxicity following radiation exposure

Description: The contribution of G{sub 2} cell cycle checkpoint control to ionizing radiation responses was examined in ten human tumor cell lines. Most of the delay in cell cycle progression seen in the first cell cycle following radiation exposure was due to blocks in G{sub 2} and there were large cell line-to-cell line variations in the length of the G{sub 2} block. Longer delays were seen in cell lines that had mutations in p53. There was a highly significant inverse correlation between the length of G{… more
Date: August 1997
Creator: Schwartz, J. L.; Cowan, J. & Grdina, D. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chronic and Acute Radiation of Microsporogenesis and Mature Pollen in Quercus

Description: The production of pollen under conditions of chronic gamma irradiation was investigated for three oak species. Two chronically irradiated areas were studied: a low level (1 to 15r/day) area where trees had received varying amounts of radiation over a period of 11 years, and a second area receiving gamma radiation for about five months previous to the investigation. In the latter study dose levels ranged from lethal (45r/day) to a region of no detectable effect. In both areas pollen abortion sho… more
Date: January 1, 1963
Creator: Stairs, G. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Validated High-Let Radiation Specific Biomarker in the Mayak Worker Cohort

Description: Our goal (see Project Objectives) is to deliver a dosimetry system which will enable both a Pu body burden of 0.3 kBq, and a 30 cGy {gamma} ray dose, to be separately estimated with a confidence limit of {+-}30%. In terms of the numbers analyzed and the data we have accrued, we have direct quantitative evidence that we are on track to providing such a comprehensive independent dosimetry system for Mayak workers. We had previously demonstrated that intra-chromosomal aberrations measured in perip… more
Date: December 11, 2006
Creator: David J. Brenner, Ph.D., D.Sc. & Tamara Azizova, M.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Mechanisms and consequences of paternally transmitted chromosomal abnormalities

Description: Paternally transmitted chromosomal damage has been associated with pregnancy loss, developmental and morphological defects, infant mortality, infertility, and genetic diseases in the offspring including cancer. There is epidemiological evidence linking paternal exposure to occupational or environmental agents with an increased risk of abnormal reproductive outcomes. There is also a large body of literature on germ cell mutagenesis in rodents showing that treatment of male germ cells with mutage… more
Date: April 5, 2005
Creator: Marchetti, F & Wyrobek, A J
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Induction of Genomic Instability In Vivo by Low Doses of 137Cs gamma rays

Description: The overall goal of this project is to determine if low doses (below or equal to the level traditionally requiring human radiation protection, i.e. less than or equal to 10 cGy) of low LET radiation can induce genomic instability. The magnitude of genomic instability was measured as delayed chromosome instability in bone marrow cells of exposed mice with different levels of endogenous DNA-dependent protein kinase catalytic subunit (DNA-PKcs) activity, i.e. high (C57BL/6J mice), intermediate (BA… more
Date: January 6, 2006
Creator: Rithidech, Kanokporn; Simon, Sanford, R. & Whorton, Elbert, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Field-flow fractionation of chromosomes

Description: The work done on this project is divided into two principal areas. The first involves the application of sedimentation/steric FFF to metaphase chromosomes in an attempt to fractionate the chromosomes according to their size. The preparation of chromosomes from a number of organisms was attempted; procedures were finally worked out in collaboration with Los Alamos National Laboratory for the preparation of metaphase chromosomes from Chinese hamster cells. After extensive experimental work was do… more
Date: September 1, 1991
Creator: Giddings, J.C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Theoretical approach to the effects of extremely low freqency electromagnetic fiels on Physarum polycephalum. [Slime molds]

Description: Absolute reaction rate theory is applied to explain the increased time between successive synchronous mitotic division of the slime mold Physarum polycephalum when exposed to extremely low frequency electromagnetic fields. By ignoring the transition period from the normal (control) mitotic cycle to the lengthened mitotic cycle of exposed P. polycephalum, the change in the activation energy is established. This activation energy is in the range of enzyme-catalyzed reactions. The influence of cha… more
Date: March 1, 1977
Creator: Wayland, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Smad3 recruits the anaphase-promoting complex for ubiquitination and degradation of SnoN

Description: Smad proteins mediate transforming growth factor-b signaling to regulate cell growth and differentiation. SnoN is an important negative regulator of TGFb signaling that functions to maintain the repressed state of TGFb target genes in the absence of ligand. Upon TGFb stimulation, Smad3 and Smad2 translocate into the nucleus and induce a rapid degradation of SnoN, allowing activation of TGFb target genes. Here we show that Smad2- or Smad3-induced degradation of SnoN requires the ubiquitin-depend… more
Date: September 11, 2001
Creator: Stroschein, Shannon L.; Bonni, Shirin; Wrana, Jeffrey L. & Luo, Kunxin
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Programmed Cell Death During Female Gametophyte Development

Description: Endosperm is a storage tissue in the angiosperm seed that is important both biologically and agriculturally. Endosperm is biologically important because it provides nutrients to the embryo during seed development and agriculturally important because it is a significant source of food, feed, and industrial raw materials. Approximately two-thirds of human calories are derived from endosperm, either directly or indirectly through animal feed. Furthermore, endosperm is used as a raw material for nu… more
Date: September 15, 2004
Creator: Drews, Gary, N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Molecular events basic to cellular radiation response

Description: The initiation and control of the division process in normal cells is studied to gain insight into changes in these regards caused by x-irradiation and neoplasia. The Primer Hypothesis for eukaryotic gene regulation proposes that small molecular weight RNA acts as primer for new RNA synthesis by hybridizing with DNA and there initiating the transcription of a new RNA chain. The experiments reported here indicate that small molecular weight RNA will induce the production of new proteins. These r… more
Date: unknown
Creator: Kolodny, G. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Control points within the cell cycle

Description: Evidence of the temporal order of chromosomal DNA replication argues favorably for the view that the cell cycle is controlled by genes acting in sequence whose time of expression is determined by mitosis and the amount of nuclear DNA (2C vs 4C) in the cell. Gl and G2 appear to be carbohydrate dependent in that cells starved of either carbohydrate of phosphate fail to make these transitions. Cells deprived of nitrate, however, fail only at Gl to S transition indicating that the controls that ope… more
Date: January 1, 1984
Creator: Van't Hof, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Spatiotemporal characterization of ionizing radiation induced DNA damage foci and their relation to chromatin organization

Description: DNA damage sensing proteins have been shown to localize to the sites of DSB within seconds to minutes following ionizing radiation (IR) exposure, resulting in the formation of microscopically visible nuclear domains referred to as radiation-induced foci (RIF). This review characterizes the spatio-temporal properties of RIF at physiological doses, minutes to hours following exposure to ionizing radiation, and it proposes a model describing RIF formation and resolution as a function of radiation … more
Date: September 15, 2009
Creator: Costes, Sylvain V; Chiolo, Irene; Pluth, Janice M.; Barcellos-Hoff, Mary Helen & Jakob, Burkhard
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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