The inhibition of radiation-induced mutagenesis by the combined effects of selenium and the aminothiol WR-1065

1996 ◽  
Vol 356 (2) ◽  
pp. 147-154 ◽  
Author(s):  
Alan M. Diamond ◽  
Phylis Dale ◽  
Judith L. Murray ◽  
David J. Grdina
Keyword(s):  
Combined Effects ◽  
Radiation Induced ◽  
Induced Mutagenesis

Developing a Genetic System in Deinococcus radiodurans for Analyzing Mutations

Genetics ◽  
2004 ◽  
Vol 166 (2) ◽  
pp. 661-668
Author(s):  
Mandy Kim ◽  
Erika Wolff ◽  
Tiffany Huang ◽  
Lilit Garibyan ◽  
Ashlee M Earl ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Deinococcus Radiodurans ◽  
Genetic System ◽  
Base Change ◽  
Base Substitution ◽  
Wild Type ◽  
Base Pairs ◽  
E Coli ◽  
Radiation Induced ◽  
Induced Mutagenesis

Abstract We have applied a genetic system for analyzing mutations in Escherichia coli to Deinococcus radiodurans, an extremeophile with an astonishingly high resistance to UV- and ionizing-radiation-induced mutagenesis. Taking advantage of the conservation of the β-subunit of RNA polymerase among most prokaryotes, we derived again in D. radiodurans the rpoB/Rif r system that we developed in E. coli to monitor base substitutions, defining 33 base change substitutions at 22 different base pairs. We sequenced >250 mutations leading to Rif r in D. radiodurans derived spontaneously in wild-type and uvrD (mismatch-repair-deficient) backgrounds and after treatment with N-methyl-N′-nitro-N-nitrosoguanidine (NTG) and 5-azacytidine (5AZ). The specificities of NTG and 5AZ in D. radiodurans are the same as those found for E. coli and other organisms. There are prominent base substitution hotspots in rpoB in both D. radiodurans and E. coli. In several cases these are at different points in each organism, even though the DNA sequences surrounding the hotspots and their corresponding sites are very similar in both D. radiodurans and E. coli. In one case the hotspots occur at the same site in both organisms.

scholarly journals Coexistence of SOS-Dependent and SOS-Independent Regulation of DNA Repair Genes in Radiation-Resistant Deinococcus Bacteria

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 924
Author(s):  
Laurence Blanchard ◽  
Arjan de Groot
Keyword(s):  
Dna Repair ◽  
Deinococcus Radiodurans ◽  
Dna Repair Genes ◽  
Lesion Bypass ◽  
Radiation Resistant ◽  
Radiation Induced ◽  
Induced Mutagenesis ◽  
High Doses ◽  
Translesion Polymerases ◽  
Repair Genes

Deinococcus bacteria are extremely resistant to radiation and able to repair a shattered genome in an essentially error-free manner after exposure to high doses of radiation or prolonged desiccation. An efficient, SOS-independent response mechanism to induce various DNA repair genes such as recA is essential for radiation resistance. This pathway, called radiation/desiccation response, is controlled by metallopeptidase IrrE and repressor DdrO that are highly conserved in Deinococcus. Among various Deinococcus species, Deinococcus radiodurans has been studied most extensively. Its genome encodes classical DNA repair proteins for error-free repair but no error-prone translesion DNA polymerases, which may suggest that absence of mutagenic lesion bypass is crucial for error-free repair of massive DNA damage. However, many other radiation-resistant Deinococcus species do possess translesion polymerases, and radiation-induced mutagenesis has been demonstrated. At least dozens of Deinococcus species contain a mutagenesis cassette, and some even two cassettes, encoding error-prone translesion polymerase DnaE2 and two other proteins, ImuY and ImuB-C, that are probable accessory factors required for DnaE2 activity. Expression of this mutagenesis cassette is under control of the SOS regulators RecA and LexA. In this paper, we review both the RecA/LexA-controlled mutagenesis and the IrrE/DdrO-controlled radiation/desiccation response in Deinococcus.

The Combined Effects of Cycling Endurance and TID on Floating Gate Memory Cells

2021 ◽  
Author(s):  
Side Song ◽  
Guozhu Liu ◽  
Qi He ◽  
Xiang Gu ◽  
Genshen Hong ◽  
...  
Keyword(s):  
Radiation Effects ◽  
Memory Cell ◽  
Floating Gate ◽  
Combined Effects ◽  
Memory Cells ◽  
Threshold Voltage Shift ◽  
Floating Gate Memory ◽  
Interface Generation ◽  
Radiation Hardened ◽  
Radiation Induced

Abstract In this paper, the combined effects of cycling endurance and radiation on floating gate memory cell are investigated in detail, the results indicate that: 1.The programmed flash cells with a prior appropriate number of program and erase cycling stress exhibit much smaller threshold voltage shift than their counterpart in response to radiation, which is mainly ascribed to the recombination of trapped electrons (introduced by cycling stress) and trapped holes (introduced by irradiation) in the oxide surrounding the floating gate; 2.The radiation induced transconductance degradation in prior cycled flash cell is more severe than those without cycling stress in both of the programmed state and erased state; 3. Radiation is more likely to induce interface generation in programmed state than in erased state. This paper will be useful in understanding the issues involved in cycling endurance and radiation effects as well as in designing radiation hardened floating gate memory cells.

COMBINED EFFECTS OF EGG AGE AND RADIATION DOSAGE ON EGG HATCH OF TENEBRIO MOLITOR (COLEOPTERA: TENEBRIONIDAE)

1972 ◽  
Vol 104 (1) ◽  
pp. 141-144 ◽  
Author(s):  
John H. Brower
Keyword(s):  
Gamma Radiation ◽  
Radiation Dosage ◽  
Age Groups ◽  
Fold Increase ◽  
Tenebrio Molitor ◽  
Combined Effects ◽  
Egg Hatch ◽  
Egg Mortality ◽  
Radiation Induced ◽  
Coleoptera Tenebrionidae

AbstractTenebrio molitor L. eggs in 15 age groups ranging from 0.5 to 7.5 days were irradiated with 10 dosages of gamma radiation ranging from 0.5 to 160 krad. The study showed that age had a pronounced effect on radiation-induced egg mortality. There was a 250-fold increase in resistance as eggs matured from 0.5 to 7.5 days as measured by the dosage required to produce an LD50.

Gamma radiation induced mutagenesis in Aspergillus niger to enhance its microbial fermentation activity for industrial enzyme production

2010 ◽  
Vol 38 (2) ◽  
pp. 1367-1374 ◽  
Author(s):  
M. Siddique Awan ◽  
Nabila Tabbasam ◽  
N. Ayub ◽  
M. E. Babar ◽  
Mehboob-ur-Rahman ◽  
...  
Keyword(s):  
Aspergillus Niger ◽  
Gamma Radiation ◽  
Enzyme Production ◽  
Microbial Fermentation ◽  
Industrial Enzyme ◽  
Radiation Induced ◽  
Induced Mutagenesis

scholarly journals Recovery of a low mutant frequency after ionizing radiation-induced mutagenesis during spermatogenesis

2008 ◽  
Vol 654 (2) ◽  
pp. 150-157 ◽  
Author(s):  
Guogang Xu ◽  
Gabriel W. Intano ◽  
John R. McCarrey ◽  
Ronald B. Walter ◽  
C. Alex McMahan ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Radiation Induced ◽  
Induced Mutagenesis ◽  
Mutant Frequency

scholarly journals Comparative Analysis Reveals Changes in Some Seed Properties in Amaranth Mutant Variety ‘Zobor’ (A. hypochondriacus × A. hybridus)

Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2565
Author(s):  
Andrea Hricová ◽  
Veronika Mistríková ◽  
Alena Gajdošová ◽  
Jozef Fejér ◽  
Jana Nôžková ◽  
...  
Keyword(s):  
Seed Weight ◽  
Amylose Content ◽  
Mutation Breeding ◽  
Pasting Properties ◽  
Phenotypic Characterization ◽  
New Variety ◽  
Yield Trait ◽  
Radiation Induced ◽  
Induced Mutagenesis

The aim of our long-term research program is to improve the quality and quantity of amaranth production through mutation breeding using γ-radiation. In this paper, we present the characterization of the new variety ‘Zobor’ of A. hypochondriacus × A. hybridus developed by radiation-induced mutagenesis of hybrid K-433. Multiyear phenotypic characterization of an important yield parameter (1000-seed weight) showed that the studied mutant variety ‘Zobor’ has an advantage in seed weight over the nonirradiated control seeds of K-433 with predictable performance of this yield trait. ‘Zobor’ exhibited changes in seed morphometric parameters, starch particle size, and pasting properties with no change in amylose content and swelling power. Moreover, the seeds of ‘Zobor’ showed the significantly highest folate content among selected amaranth varieties. The mutant variety could, therefore, be interesting for the development of functional foods and as a low-management crop, attractive for cultivation in Europe.

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