scholarly journals RecO Is Essential for DNA Damage Repair in Deinococcus radiodurans

2008 ◽  
Vol 190 (7) ◽  
pp. 2624-2628 ◽  
Author(s):  
Guangzhi Xu ◽  
Liangyan Wang ◽  
Huan Chen ◽  
Huiming Lu ◽  
Nanjiao Ying ◽  
...  
Keyword(s):  
Direct Evidence ◽  
Deinococcus Radiodurans ◽  
Uv Light ◽  
Vital Role ◽  
Growth Defect ◽  
Replacement Method ◽  
Damage Repair ◽  
Extreme Sensitivity ◽  
Recf Pathway

ABSTRACT Here we present direct evidence for the vital role of RecO in Deinococcus radiodurans's radioresistance. A recO null mutant was constructed using a deletion replacement method. The mutant exhibited a growth defect and extreme sensitivity to irradiation with gamma rays and UV light. These results suggest that DNA repair in this organism occurs mainly via the RecF pathway.

Synaptojanin family members are implicated in endocytic membrane traffic in yeast

1998 ◽  
Vol 111 (22) ◽  
pp. 3347-3356 ◽  
Author(s):  
B. Singer-Kruger ◽  
Y. Nemoto ◽  
L. Daniell ◽  
S. Ferro-Novick ◽  
P. De Camilli
Keyword(s):  
Synaptic Vesicles ◽  
Direct Evidence ◽  
Family Members ◽  
Fluid Phase ◽  
Growth Defect ◽  
Temperature Sensitive ◽  
Close Link ◽  
Fluid Phase Endocytosis ◽  
Synaptojanin 1

The synaptojanins represent a subfamily of inositol 5′-phosphatases that contain an NH2-terminal Sac1p homology domain. A nerve terminal-enriched synaptojanin, synaptojanin 1, was previously proposed to participate in the endocytosis of synaptic vesicles and actin function. The genome of Saccharomyces cerevisiae contains three synaptojanin-like genes (SJL1, SJL2 and SJL3), none of which is essential for growth. We report here that a yeast mutant lacking SJL1 and SJL2 (Deltasjl1 Deltasjl2) exhibits a severe defect in receptor-mediated and fluid-phase endocytosis. A less severe endocytic defect is present in a Deltasjl2 Deltasjl3 mutant, while endocytosis is normal in a Deltasjl1 Deltasjl3 mutant. None of the mutants are impaired in invertase secretion. The severity of the endocytic impairment of the sjl double mutants correlates with the severity of actin and polarity defects. Furthermore, the deletion of SJL1 suppresses the temperature-sensitive growth defect of sac6, a mutant in yeast fimbrin, supporting a role for synaptojanin family members in actin function. These findings provide a first direct evidence for a role of synaptojanin family members in endocytosis and provide further evidence for a close link between endocytosis and actin function.

scholarly journals Effect of a recD Mutation on DNA Damage Resistance and Transformation in Deinococcus radiodurans

2007 ◽  
Vol 189 (14) ◽  
pp. 5101-5107 ◽  
Author(s):  
Matthew D. Servinsky ◽  
Douglas A. Julin
Keyword(s):  
Hydrogen Peroxide ◽  
Dna Damage ◽  
Ionizing Radiation ◽  
Mitomycin C ◽  
Deinococcus Radiodurans ◽  
Uv Light ◽  
Gene Encoding ◽  
Significant Similarity ◽  
Damage Repair ◽  
Recbcd Enzyme

ABSTRACT The bacterium Deinococcus radiodurans is resistant to extremely high levels of DNA-damaging agents such as UV light, ionizing radiation, and chemicals such as hydrogen peroxide and mitomycin C. The organism is able to repair large numbers of double-strand breaks caused by ionizing radiation, in spite of the lack of the RecBCD enzyme, which is essential for double-strand DNA break repair in Escherichia coli and many other bacteria. The D. radiodurans genome sequence indicates that the organism lacks recB and recC genes, but there is a gene encoding a protein with significant similarity to the RecD protein of E. coli and other bacteria. We have generated D. radiodurans strains with a disruption or deletion of the recD gene. The recD mutants are more sensitive than wild-type cells to irradiation with gamma rays and UV light and to treatment with hydrogen peroxide, but they are not sensitive to treatment with mitomycin C and methyl methanesulfonate. The recD mutants also show greater efficiency of transformation by exogenous homologous DNA. These results are the first indication that the D. radiodurans RecD protein has a role in DNA damage repair and/or homologous recombination in the organism.

scholarly journals Induction of a Futile Embden-Meyerhof-Parnas Pathway in Deinococcus radiodurans by Mn: Possible Role of the Pentose Phosphate Pathway in Cell Survival

2000 ◽  
Vol 66 (1) ◽  
pp. 105-112 ◽  
Author(s):  
Y.-M. Zhang ◽  
T.-Y. Wong ◽  
L.-Y. Chen ◽  
C.-S. Lin ◽  
J.-K. Liu
Keyword(s):  
Pentose Phosphate Pathway ◽  
Statistical Models ◽  
Deinococcus Radiodurans ◽  
Uv Light ◽  
Pentose Phosphate ◽  
Marginal Effect ◽  
Biomass Formation

ABSTRACT Statistical models were used to predict the effects of tryptone, glucose, yeast extract (TGY) and Mn on biomass formation of the highly radioresistant bacterium Deinococcus radiodurans. Results suggested that glucose had marginal effect on biomass buildup, but Mn was a significant factor for biomass formation. Mn also facilitated glucose interactions with other nutrient components. These predictions were verified by in vivo and in vitro experiments. TGY-grown cells metabolized glucose solely by the pentose phosphate pathway (PPP). Although only a fraction of glucose from the medium was transported into the cells, glucose was incorporated into the DNA efficiently after cells were exposed to UV light. The presence of glucose also enhanced the radioresistance of the culture. Mn could induce an Embden-Meyerhof-Parnas (EMP) pathway in D. radiodurans. The EMP pathway and the PPP of the Mn-treated cells oxidized glucose simultaneously at a 6:1 ratio. Although glucose was hydrolyzed rapidly by the Mn-treated cells, most glucose was released as CO2. Mn-treated cultures retained less glucose per cell than cells grown without Mn, and still less glucose was incorporated into the DNA after cells were exposed to UV light. Mn-treated cells were also more sensitive to UV light. Results suggested that metabolites of glucose generated from the PPP enhanced the survival of D. radiodurans. Induction of the EMP pathway by Mn may deplete metabolites for DNA repair and may induce oxidative stress for the cell, leading to reduction of radioresistance.

scholarly journals TRIM66 reads unmodified H3R2K4 and H3K56ac to respond to DNA damage in embryonic stem cells

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Jiajing Chen ◽  
Zikang Wang ◽  
Xudong Guo ◽  
Fudong Li ◽  
Qingtao Wei ◽  
...  
Keyword(s):  
Stem Cells ◽  
Dna Damage ◽  
Embryonic Stem Cells ◽  
Critical Role ◽  
Embryonic Stem ◽  
Genomic Stability ◽  
Vital Role ◽  
Damage Repair ◽  
The Relationship

Abstract Recognition of specific chromatin modifications by distinct structural domains within “reader” proteins plays a critical role in the maintenance of genomic stability. However, the specific mechanisms involved in this process remain unclear. Here we report that the PHD-Bromo tandem domain of tripartite motif-containing 66 (TRIM66) recognizes the unmodified H3R2-H3K4 and acetylated H3K56. The aberrant deletion of Trim66 results in severe DNA damage and genomic instability in embryonic stem cells (ESCs). Moreover, we find that the recognition of histone modification by TRIM66 is critical for DNA damage repair (DDR) in ESCs. TRIM66 recruits Sirt6 to deacetylate H3K56ac, negatively regulating the level of H3K56ac and facilitating the initiation of DDR. Importantly, Trim66-deficient blastocysts also exhibit higher levels of H3K56ac and DNA damage. Collectively, the present findings indicate the vital role of TRIM66 in DDR in ESCs, establishing the relationship between histone readers and maintenance of genomic stability.

Involvement of RecG in H2O2-induced damage repair in Deinococcus radiodurans

2009 ◽  
Vol 55 (7) ◽  
pp. 841-848 ◽  
Author(s):  
Yuanyuan Wu ◽  
Weiwei Chen ◽  
Ye Zhao ◽  
Hong Xu ◽  
Yuejin Hua
Keyword(s):  
Oxidative Damage ◽  
Type Strain ◽  
Deletion Mutant ◽  
Wild Type Strain ◽  
Deinococcus Radiodurans ◽  
Growth Defect ◽  
Great Decrease ◽  
Wild Type ◽  
Damage Repair ◽  
Chemically Induced

Deinococcus radiodurans (ex Raj et al. 1960) Brooks and Murray 1981 is well known for its efficient repair of various types of physically or chemically induced DNA damage caused by ionizing and ultraviolet radiation or H2O2. RecG codes for a helicase that is known to be involved in repairing oxidative damage in other bacterium. In this work, we constructed a DRrecG deletion mutant and investigated its possible role in H2O2-induced damage. The results showed that the deletion of DRrecG resulted in an obvious growth defect and great decrease of radioresistance of D. radiodurans to gamma radiation and H2O2. We also defined the transcriptional profiles of the recG mutant and wild-type strain with and without treatment with H2O2. These results suggested that DRrecG is important for DNA repair during oxidative damage.

Asiana Airlines Flight 214

2014 ◽  
Vol 4 (2) ◽  
pp. 113-121 ◽  
Author(s):  
Stephanie Chow ◽  
Stephen Yortsos ◽  
Najmedin Meshkati
Keyword(s):  
Human Factors ◽  
Aviation Safety ◽  
Cultural Factors ◽  
Vital Role ◽  
Cultural Issues ◽  
Flight Crew ◽  
Pilot Performance ◽  
Engineering Designs ◽  
Flight Deck

This article focuses on a major human factors–related issue that includes the undeniable role of cultural factors and cockpit automation and their serious impact on flight crew performance, communication, and aviation safety. The report concentrates on the flight crew performance of the Boeing 777–Asiana Airlines Flight 214 accident, by exploring issues concerning mode confusion and autothrottle systems. It also further reviews the vital role of cultural factors in aviation safety and provides a brief overview of past, related accidents. Automation progressions have been created in an attempt to design an error-free flight deck. However, to do that, the pilot must still thoroughly understand every component of the flight deck – most importantly, the automation. Otherwise, if pilots are not completely competent in terms of their automation, the slightest errors can lead to fatal accidents. As seen in the case of Asiana Flight 214, even though engineering designs and pilot training have greatly evolved over the years, there are many cultural, design, and communication factors that affect pilot performance. It is concluded that aviation systems designers, in cooperation with pilots and regulatory bodies, should lead the strategic effort of systematically addressing the serious issues of cockpit automation, human factors, and cultural issues, including their interactions, which will certainly lead to better solutions for safer flights.

Direct Evidence for the Role of Inhibition in Resolving Interference

2009 ◽  
Author(s):  
M. Karl Healey ◽  
Karen L. Campbell ◽  
Lynn Hasher ◽  
Lynn Ossher
Keyword(s):  
Direct Evidence

Energy Efficiency Analysis in ERA using NFL-BA Algorithm

2020 ◽  
pp. 340-348
Author(s):  
Palky Mehta ◽  
H. L. Sharma
Keyword(s):  
Cluster Head ◽  
Vital Role ◽  
Wireless Sensor ◽  
Energy Usage ◽  
Cluster Heads ◽  
Comparison Results ◽  
Current Scenario ◽  
Energy Efficiency Analysis ◽  
Selection Of

In the current scenario of Wireless Sensor Network (WSN), power consumption is the major issue associated with nodes in WSN. LEACH technique plays a vital role of clustering in WSN and reduces the energy usage effectively. But LEACH has its own limitation in order to search cluster head nodes which are randomly distributed over the network. In this paper, ERA-NFL- BA algorithm is being proposed for selects the cluster heads in WSN. This algorithm help in selection of cluster heads can freely transform from global search to local search. At the end, a comparison has been done with earlier researcher using protocol ERA-NFL, which clearly shown that proposed Algorithm is best suited and from comparison results that ERA-NFL-BA has given better performance.

Tertiary English-majored Students’ Perceptions toward the Role of Pronunciation in English Language Learning and their Practicing Strategies

2020 ◽  
Vol 6 (2) ◽  
pp. 264-279
Keyword(s):  
Language Learning ◽  
English Language ◽  
Vital Role ◽  
English Language Learning ◽  
Structured Interviews ◽  
Efl Learners ◽  
The University

Accurate pronunciation has a vital role in English language learning as it can help learners to avoid misunderstanding in communication. However, EFL learners in many contexts, especially at the University of Phan Thiet, still encounter many difficulties in pronouncing English correctly. Therefore, this study endeavors to explore English-majored students’ perceptions towards the role of pronunciation in English language learning and examine their pronunciation practicing strategies (PPS). It involved 155 English-majored students at the University of Phan Thiet who answered closed-ended questionnaires and 18 English-majored students who participated in semi-structured interviews. The findings revealed that students strongly believed in the important role of pronunciation in English language learning; however, they sometimes employed PPS for their pronunciation improvement. Furthermore, the results showed that participants tended to use naturalistic practicing strategies and formal practicing strategies with sounds, but they overlooked strategies such as asking for help and cooperating with peers. Such findings could contribute further to the understanding of how students perceive the role of pronunciation and their PPS use in the research’s context and other similar ones. Received 10th June 2019; Revised 12th March 2020; Accepted 12th April 2020

The role of Record of Rights (Khatian) in determining title or possession: An overview

IIUC Studies ◽  
2020 ◽  
Vol 15 ◽  
pp. 33-46
Author(s):  
Kalim Ullah
Keyword(s):  
Human Life ◽  
Vital Role ◽  
Critical Element ◽  
Human Beings ◽  
Supportive Evidence ◽  
Land Administration ◽  
Holy Quran ◽  
The Holy Quran ◽  
Religious Systems

Human beings are deeply related to land. Human beings take birth on land, live on land, die on land and mixes with land ultimately. As stated in the holy Quran: ‘We (Allah) created you (human beings) from the soil, we shall make you return to the soil and We shall call you back again from the soil’ (20:55). Human life is surrounded by soil i.e. land. So, land is a highly completed issue of human life involving economic, social, political, cultural and often religious systems. Land administration is thus a critical element and often a pre-condition for peaceful society and sustainable development. In administrating land, Khatian or record of rights plays a vital role to determine the rights and interests of the respective parties as supportive evidence. In this article, discussion is mainly made on the fact that Khatian or record of rights is not a document of title solely but it may be an evidence of title as well as possession. IIUC Studies Vol.15(0) December 2018: 33-46

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