Polymerase bypass of N7-guanine monoadducts of cisplatin, diepoxybutane, and epichlorohydrin
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Jiayu Ye, Caitlin R. Farrington, Julie T. MillardAbstractDNA oligonucleotides containing site-specific N7-guanine monoadducts of cisplatin, diepoxybutane, and epichlorohydrin were used as templates for DNA synthesis by two bacterial DNA polymerases and human polymerase β. These polymerases were able to bypass the lesions effectively, although the efficiency was decreased, with inhibition increasing with the size of the lesion. Fidelity of incorporation was essentially unaltered, suggesting that N7-...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

The first (6-4) photolyase with DNA damage repair activity from the Antarctic microalga Chlamydomonas sp. ICE-L
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Meiling An, Zhou Zheng, Changfeng Qu, Xixi Wang, Hao Chen, Chongli Shi, Jinlai MiaoAbstractThe psychrophilic microalga, Chlamydomonas sp. ICE-L, isolated from floating ice in the Antarctic, one of the most highly UV exposed ecosystems on Earth, displays an efficient DNA photorepair capacity. Here, the first known (6-4) photolyase gene (6-4CiPhr) from C. sp. ICE-L was identified. The 6-4CiPhr encoded 559-amino acid polypeptide with a pI of 8.86, and had a predicted Mw of 64.2 kDa. Real-time PCR was...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Effective discovery of rare variants by pooled target capture sequencing: A comparative analysis with individually indexed target capture sequencing
In this study, we evaluated the sensitivity and specificity of sequencing for pooled DNA samples of multiple individuals (Pool-seq) as a cost-effective and robust approach for rare variant discovery. We comparatively analyzed Pool-seq vs. individual-seq of indexed target capture of up to 960 genes in ∼1000 individuals, followed by independent genotyping validation studies. We found that Pool-seq was as effective and accurate as individual-seq in detecting rare variants and accurately estimating their minor allele frequencies (MAFs). Our results suggest that Pool-seq can be used as an efficient and cost-effective method f...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Effect of age at exposure on chromosome abnormalities in MIC-exposed Bhopal population detected 30 years post-disaster
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Bani Bandana Ganguly, Shouvik Mandal, Nalok Banerjee, Nitin N. Kadam, Rita AbbiAbstractFollow-up cytogenetic study was carried out on 145 individuals from areas stratified by Indian Council of Medical Research, for evaluation of the effect of age-at-exposure and its interaction with exposure status on chromosomal aberrations (CA) in blood-lymphocytes. CA was presented as abnormal cell (Abc), aberrations (Abn) and number of aberration/abnormal cell (Abn/Abc), and correlated with age-at-exposure (chil...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

A cautionary note on the mutation frequency in microbial research
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Qi ZhengAbstractThe mutation frequency, also known as the mutant frequency, is an unnormalized quantity, and its normalized counterpart is the mutation rate. Due to historical reasons, the mutation frequency has been a predominant yardstick of microbial mutability in the field of mutator identification. While the mean mutation frequency is infamously erratic, replacing it with the median mutation frequency is not an effective remedy. By encouraging investigators to substitute mutation rates for muta...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

The presence of KRAS, PPP2R1A and ARID1A mutations in 101 Chinese samples with ovarian endometriosis
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Yang Zou, Jiang-Yan Zhou, Jiu-Bai Guo, Li-Qun Wang, Yong Luo, Zi-Yu Zhang, Fa-Ying Liu, Jun Tan, Feng Wang, Ou-Ping HuangAbstractEndometriosis is a potential premalignant disorder. The underlying molecular aberrations, however, are not fully understood. A recent exome sequencing study found that 25% (10/39) of deep infiltrating endometriosis harbored cancer driver gene mutations. However, it is unclear whether these mutations also exist in ovarian endometriosis. Here, a total of 101 ovarian endometr...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Identification of nonsynonymous TP53 mutations in hydatidiform moles
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Ka-Kui Chan, Esther Shuk-Ying Wong, Oscar Gee-Wan Wong, Hextan Yuen-Sheung Ngan, Annie Nga-Yin CheungAbstractHydatidiform mole (HM), an unusual pregnancy with pure or predominant paternal genetic contribution, is the most common form of gestational trophoblastic disease. Most HM regress after uterine evacuation but some will develop into persistent disease or even frank malignancy. Although p53 is highly expressed in HM, TP53 mutations have rarely been detected in previous studies. Here we screened ...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Eukaryotic 4Rs: DNA replication, repair, recombination, and damage response
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Kyungjae Myung (Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis)
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Eukaryotic DNA replication: Orchestrated action of multi-subunit protein complexes
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Sukhyun Kang, Mi-Sun Kang, Eunjin Ryu, Kyungjae MyungAbstractGenome duplication is an essential process to preserve genetic information between generations. The eukaryotic cell cycle is composed of functionally distinct phases: G1, S, G2, and M. One of the key replicative proteins that participate at every stage of DNA replication is the Mcm2-7 complex, a replicative helicase. In the G1 phase, inactive Mcm2-7 complexes are loaded on the replication origins by replication-initiator proteins, ORC and ...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

So similar yet so different: The two ends of a double strand break
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Keun P. Kim, Ekaterina V. MirkinAbstractHomologous recombination (HR) is essential for ensuring proper segregation of chromosomes in the first round of meiotic division. HR is also crucial for preserving genomic integrity of somatic cells due to its ability to rescue collapsed replication forks and eliminate deleterious DNA lesions, such as double-strand breaks (DSBs), interstrand crosslinks, and single-strand DNA gaps. Here, we review the early steps of HR (homology search and strand exchange), foc...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Microhomology-mediated end joining: Good, bad and ugly
Publication date: May 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 809Author(s): Ja-Hwan Seol, Eun Yong Shim, Sang Eun LeeAbstractDNA double-strand breaks (DSBs) are induced by a variety of genotoxic agents, including ionizing radiation and chemotherapy drugs for treating cancers. The elimination of DSBs proceeds via distinctive error-free and error-prone pathways. Repair by homologous recombination (HR) is largely error-free and mediated by RAD51/BRCA2 gene products. Classical non-homologous end joining (C-NHEJ) requires the Ku heterodimer and can efficiently rejoin breaks, wit...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Pattern of mitochondrial D-loop variations and their relation with mitochondrial encoded genes in pediatric acute myeloid leukemia
Publication date: July 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 810Author(s): Anudishi Tyagi, Raja Pramanik, Sreenivas Vishnubhatla, Safdar Ali, Radhika Bakhshi, Anita Chopra, Archna Singh, Sameer BakhshiAbstractRole of mitochondrial DNA variations, particularly in D loop region, remains investigational in acute myeloid leukaemia (AML). Consecutive 151 pediatric AML patients were prospectively enrolled from June 2013 to August 2016, for evaluating pattern of variations in mitochondrial D-loop region and to determine their association, if any, with expression of mitochondrial...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Prophasing interphase chromatin for assessing genetic damages—The evolution, applications and the future prospects
We present the chronological events of evolution of the PCC technique along with its applications. Also, the limitations of the technique along with the suggestions for further refinement of the PCC technique are discussed. (Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis)
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

The Adenomatous Polyposis Coli (APC) mutation spectra in different anatomical regions of the large intestine in colorectal cancer
Publication date: July 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 810Author(s): Min Zhang, Da Yang, Barry GoldAbstractThe enhanced incidence of colorectal cancer (CRC) in the U.S.A. has been linked to promutagens, such as heterocyclic aromatic amines, in the western diet that are produced by high temperature cooking of meat. However, a prior analysis of driver nonsense mutations in the Adenomatous Polyposis Coli (APC) gene, which is mutated in 75% of human CRC, indicated that the C·G → A·T transversions produced by this class of mutagens were not enriched but actually ...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research

Mutagenic potential of 8-oxo-7,8-dihydroguanine (8-oxoG) is influenced by nearby clustered lesions
Publication date: July 2018Source: Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis, Volume 810Author(s): Naoya Shikazono, Ken AkamatsuAbstractIonizing radiation causes various different types of DNA damage. If not repaired, DNA damage can have detrimental effects. Previous studies indicate that the spatial distribution of DNA lesions induced by ionizing radiation is highly relevant to the ensuing biological effects. Clustered DNA damage, consisting of DNA lesions in close proximity, has been studied in detail, and has enhanced mutagenic potential depending on the configuration of the lesions. However,...
Source: Mutation Research Fundamental and Molecular Mechanisms of Mutagenesis - July 10, 2018 Category: Cytology Source Type: research