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in subjects: "Gene Mutations"

open access

Analysis of the PS II proteins MSP and CP43

The goals of this proposal were two-fold: (1) to analyze the impact of mutations in the psbO gene (coding for the Mn-stabilizing protein, MSP) on O{sub 2}-evolution; and (2) to analyze membrane assembly in cyanobacteria, especially the effect of iron deficiency on this process. The mutations in the psbO gene were performed in the transformable and photoheterotrophic cyanobacterium Synechocystis sp. PCC6803, whereas the research with membrane assembly and iron deficiency was performed in the tra… more

Date: July 1, 1995

Creator: Sherman, L. A.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Lymphocytes from wasted mice express enhanced spontaneous and {gamma}-ray-induced apoptosis

Mice bearing the autosomal recessive mutation wasted (wst/wst) display a disease pattern including faulty repair of DNA damage in lymphocytes after radiation exposure, neurologic abnormalities, and immunodeficiency. Many of the features of this mouse model have suggested a premature or increased spontaneous frequency of apoptosis in thymocytes; past work has shown an inability to establish cultured T cell lines, an abnormally high death rate of stimulated T cells in culture, and an increased se… more

Date: September 1, 1993

Creator: Woloschak, Gayle E.; Chang-Liu, Chin-Mei; Chung, Jen & Libertin, Claudia R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Human radiation studies: Remembering the early years: Oral history of radiologist Henry I. Kohn, M.D., Ph.D., conducted September 13, 1994

This report is a transcript of an interview of Dr. Henry I. Kohn by representatives of the US DOE Office of Human Radiation Experiments. Dr. Kohn was selected for this interview because of the positions he held at Oak Ridge National Laboratory, University of California at San Francisco, and Harvard Medical School. Dr. Kohn discussed his remembrances of his experiences in blood chemistry of animals and patients exposed to radiation, and his remembrances of several radiobiologists.

Date: June 1, 1995

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

[Mechanisms of proton pumping in bacteriorhodopsin]. Progress report

This report consists of two parts namely a brief statement of the progress made during the past four years of the project and more extensive discussion of the current state of understanding of molecular mechanisms controlling the proton pump (bacteriorhodopsin). Detailed descriptions are provided of how the protein undergoes conformational changes on absorbing a photon. Studies are described where the protein structure has been manipulated and the biochemical properties are assessed.

Date: December 31, 1995

Creator: Ebrey, T.G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Multigene deletions in lung adenocarcinomas from irradiated and control mice

K-ras codon 12 point mutations mRb and p53 gene deletions were examined in tissues from 120 normal lungs and lung adenocarcinomas that were Formalin-treated and paraffin-embedded 25 years ago. The results showed that 12 of 60 (20%) lung adenocarcinomas had mRb deletions. All lung adenocarcinomas that were initially found bearing deleted mRb had p53 deletions (15 of 15; 100%). A significantly higher mutation frequency for K-ras codon 12 point mutations was also found in the lung adenocarcinomas … more

Date: June 1, 1996

Creator: Zhang, Yueru & Woloschak, Gayle E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An atomic view of additive mutational effects in a protein structure

Substitution of a single amino acid in a protein will often lead to substantial changes in properties. If these properties could be altered in a rational way then proteins could be readily generated with functions tailored to specific uses. When amino acid substitutions are made at well-separated locations in a single protein, their effects are generally additive. Additivity of effects of amino acid substitutions is very useful because the properties of proteins with any combination of substitu… more

Date: April 1, 1996

Creator: Skinner, M. M. & Terwilliger, T. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

WR-2721 protects against cytoxan-induced hprt mutagenesis without affecting therapeutic effectiveness

The radioprotector S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) was evaluated for its ability to protect against cytoxan-induced mutagenesis at the hypoxanthine-guanine phosphoribosyl transferase (hprt) locus in mouse splenocytes under conditions that would not interfere with the therapeutic effectiveness of cytoxan in the treatment of fibrosarcoma lung tumors. Mutations at the hprt locus increase in frequency as a function of the dose of cytoxan used. With a spontaneous mutation… more

Date: December 31, 1995

Creator: Kataoka, Yasushi; Perrin, J.; Hunter, N.; Milas, L. & Grdina, D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Changes in gene expression associated with radiation exposure

Current research from our group has demonstrated differences in gene induction patterns for high- and low-linear energy transfer radiations; some genes are induced selectively following neutron exposure, others selectively following {gamma}-ray exposure, and others induced following exposure to either. These genes are associated with a broad array of different functions including apoptosis, cytoskeletal function, and gene regulation (dd-RT-PCR) technology to identify genes induced following exp… more

Date: December 1995

Creator: Woloschak, G. E.; Paunesku, T.; Chang-Liu, C. M. & Grdina, D. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Compensation for L212GLU in bacterial reaction centers

In wild-type bacterial reaction centers (RC), residue L212Glu, which is located about 5 {Angstrom} away from Q{sub B}, is involved in the delivery of the second proton to Q{sub B{sup 2}{minus}} [1-4]. We previously constructed the L212Glu-L213Asp {yields} Ala-Ala double mutant of Rhodobacter capsulatus, and it is incapable of photosynthetic growth (PS{sup {minus}}) due to interruption of the proton transfer pathway to Q{sub B}[3,4]. We have isolated several photocompetent (PS{sup +}) phenotypic… more

Date: December 31, 1995

Creator: Hanson, D. K.; Deng, Y. L.; Schiffer, M. & Sebban, P.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Catalytic activity of nuclease P1: Experiment and theory

Nuclease P1 from Penicillium citrinum is a zinc dependent glyco-enzyme that recognizes single stranded DNA and RNA as substrates and hydrolyzes the phosphate ester bond. Nuclease Pl seems to recognize particular conformations of the phosphodiester backbone and shows significant variation in the rate of hydrolytic activity depending upon which nucleosides are coupled by the phosphodiester bond. The efficiency of nuclease Pl in hydrolyzing the phosphodiester bonds of a substrate can be altered by… more

Date: October 1, 1994

Creator: Miller, J. H.; Falcone, J. M.; Shibata, M. & Box, H. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Effects of cavities in the bacterial reaction center

A site-specific double mutant of Rhodobacter capsulatus, in which the large aromatic residues M208Tyr and L181Phe in the interior of the photosynthetic reaction center (RC) complex were replaced by smaller theonine residues, showed a dramatic reduction in the number of assembled complexes and was incapable of photosynthetic growth. The cavity created by the smaller side chains interferes mostly with the assembly of the complex. Phenotypic revertants were recovered in which a spontaneous second-… more

Date: December 31, 1995

Creator: Schiffer, M.; Deng, Y. -L.; Marrufo, A. & Hanson, D. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Positional cloning of disease genes on chromosome 16

The project seeks to elucidate the molecular basis of an important genetic disease (Batten`s disease) by molecular cloning of the affected gene by utilizing an overlapping clone map of chromosome 16. Batten disease (also known as juvenile neuronal ceroid lipofuscinosis) is a recessively inherited neurodegenerative disorder of childhood characterized by progressive loss of vision, seizures, and psychomoter disturbances. The Batten disease gene was genetically mapped to the chromosome region 16p … more

Date: April 1, 1996

Creator: Doggett, N.; Bruening, M.; Callen, D.; Gardiner, M. & Lerner, T.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Project report to STB/UO, Northern New Mexico Community College two- year college initiative: Biotechnology

This report summarizes the experiences gained in a project involving faculty direct undergraduate research focused on biotechnology and its applications. The biology program at Northern New Mexico Community College has been involved in screening for mutations in human DNA and has developed the ability to perform many standard and advanced molecular biology techniques. Most of these are based around the polymerase chain reaction (PCR) and include the use of single strand conformation polymorphis… more

Date: March 1, 1996

Item Type: Report

Partner: UNT Libraries Government Documents Department

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The nature and alternate rates of the ribulose 1,5-bisphosphate (RuBP) carboxylase/oxygenase (Rubisco) oxygenation intermediate

Mutant ribulose 1,5-bisphosphate (RuBP) were employed to investigate the partitioning of carbon flow between photosynthesis or photorespiration. Previous functional and structural studies implicate active site Lys329 and Glu48 or R. rubrum RuBp in promoting addition of CO2 to the RuBP-enediol. Two novel O2-dependent side products generated by the K329A and E49Q mutants provided insight into RuBP oxygenase intermediate and roles of Lys329 and Glu48 in oxygenation.

Date: December 31, 1995

Creator: Harpel, M. R.; Chen, Yuh-Ru & Hartman, F. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Recent advances in lung cancer biology

This paper provides an overview of carcinogenesis, especially as related to lung cancers. Various growth factors and their mutated forms as oncogenes are discussed with respect to gene location and their role in the oncogenic process. Finally the data is related to lung cancer induction in uranium miners and exposure to radon.

Date: December 31, 1995

Creator: Lechner, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Catalytic roles of flexible regions at the active site of ribulose-bisphosphate carboxylase/oxygenase (Rubisco)

Chemical and mutagenesis studies of Rubisco have identified Lys329 and Glu48 as active-site residues that are located in distinct, interacting domains from adjacent subunits. Crystallographic analyses have shown that Lys329 is the apical residue in a 12-residue flexible loop (loop 6) of the {Beta},{alpha}-barrel domain of the active site and that Glu48 resides at the end of helix B of the N-terminal domain of the active site. When phosphorylated ligands are bound by the enzyme, loop 6 adopts a … more

Date: December 31, 1995

Creator: Hartman, F. C.; Harpel, M. R.; Chen, Yuh-Ru; Larson, E. M. & Larimer, F. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

9. international mouse genome conference

This conference was held November 12--16, 1995 in Ann Arbor, Michigan. The purpose of this conference was to provide a multidisciplinary forum for exchange of state-of-the-art information on genetic mapping in mice. This report contains abstracts of presentations, focusing on the following areas: mutation identification; comparative mapping; informatics and complex traits; mutagenesis; gene identification and new technology; and genetic and physical mapping.

Date: December 31, 1995

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

The effect of oligosaccharides on glycoprotein stability

A series of experiments aimed at determining the sites of glycosylation of Staphylococcal nuclease (SNase) were conducted.

Date: December 31, 1995

Creator: Goochee, C.F. & Khosla, C.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Diagnostics microchips: detection of beta-thalassemia mutations by hybridization with an oligonucleotide array

A reliable identification of genomic heterozygous and homozygous beta- thalassemia mutations in a yes or no way was demonstrated with microchips.

Date: October 1, 1996

Creator: Mirzabekov, A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Disability rights in dialogue with clinical genetics conference, May 31 to June 2, 1996

The issue of prenatal diagnosis and selective abortion has been hotly debated in the medical, genetic counselling, feminist, parents, disability rights and bio-ethics literature, each of the various positions critiquing each other. People from the disability rights community in particular have began to articulate a critical view of the practice of widespread prenatal diagnosis with intent to abort because the pregnancy might result in a child with a disability. Unfortunately, people from the va… more

Date: December 31, 1996

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

From photons to protons in the photocycle of bacterial reaction center

The detailed knowledge of the atomic coordinates of the bacterial reaction center (RC) has permitted a close scrutiny of structure/function relationships not only of the quinones but of the protein itself with its internal water structure. Protonatable groups were identified as intrinsic part of the redox reactions, providing charge compensation and forming channels for the movement of hydrogen ions to QB2-. The nature and position of these groups give rise to electrostatic profiles that determ… more

Date: December 31, 1995

Creator: Maroti, P., Osvath, S., Tapai, C., Hanson, D.K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

A molecular genetic approach to understanding eukaryotic cellulose synthesis. Final technical report, March 15, 1995--March 14, 1997

In an attempt to understand eukaryotic cellulose synthesis, this research investigates the cellulose biosynthetic pathway of Dictyostelium discoideum. Attention is focused on the following: use of a newly developed method of tagged insertional mutagenesis to generate mutants in cellulose biosynthesis; and exploiting the monolayer culture system to identify differences in mRNA populations between DIF-induced (and cellulose-synthesizing) versus non-induced cells.

Date: November 1, 1997

Creator: Blanton, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Wasted (wst) mice have 3-bp deletion in the PCNA promoter

Mice homozygous for the autosomal recessive wasted mutation (wst/wst) have abnormalities in T-lymphocytes and in the anterior motor neuron cells of the spinal cord, leading to sensitivity to ionizing radiation, hind limb paralysis, and immunodeficiency. This defect results in a failure to gain weight by 20 days and death at 28 days of age. Previous results from the authors` group have shown that (1) wasted mice have little if any detectable PCNA protein or mRNA in thymus, but levels in liver, b… more

Date: August 1, 1997

Creator: Paunesku, Tatjana & Woloschak, Gayle E.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

The fatty liver dystrophy (fld) mutation: Developmentally related alterations in hepatic triglyceride metabolism and protein expression

Fatty liver dystrophy (fld) is an autosomal recessive mutation in mice characterized by hypertriglyceridemia and development of a fatty liver in the early neonatal period. Also associated with the fld phenotype is a tissue-specific deficiency in the expression of lipoprotein lipase and hepatic lipase, as well as elevations in hepatic apolipoprotein A-IV and apolipoprotein C-II mRNA levels. Although these lipid abnormalities resolve at the age of weaning, adult mutant mice exhibit a peripheral n… more

Date: July 1, 1997

Creator: Reue, K.; Rehnmark, S.; Cohen, R. D.; Leete, T. H.; Doolittle, M. H.; Giometti, C. S. et al.

Item Type: Report

Partner: UNT Libraries Government Documents Department