Genome Stability

Genome Stability: From Virus to Human Application, Second Edition, a volume in the Translational Epigenetics series, explores how various species maintain genome stability and genome diversification in response to environmental factors. Here, across thirty-eight chapters, leading researchers provide a deep analysis of genome stability in DNA/RNA viruses, prokaryotes, single cell eukaryotes, lower multicellular eukaryotes, and mammals, examining how epigenetic factors contribute to genome stability and how these species pass memories of encounters to progeny. Topics also include major DNA repair mechanisms, the role of chromatin in genome stability, human diseases associated with genome instability, and genome stability in response to aging. This second edition has been fully revised to address evolving research trends, including CRISPRs/Cas9 genome editing; conventional versus transgenic genome instability; breeding and genetic diseases associated with abnormal DNA repair; RNA and extrachromosomal DNA; cloning, stem cells, and embryo development; programmed genome instability; and conserved and divergent features of repair. This volume is an essential resource for geneticists, epigeneticists, and molecular biologists who are looking to gain a deeper understanding of this rapidly expanding field, and can also be of great use to advanced students who are looking to gain additional expertise in genome stability. A deep analysis of genome stability research from various kingdoms, including epigenetics and transgenerational effects Provides comprehensive coverage of mechanisms utilized by different organisms to maintain genomic stability Contains applications of genome instability research and outcomes for human disease Features all-new chapters on evolving areas of genome stability research, including CRISPRs/Cas9 genome editing, RNA and extrachromosomal DNA, programmed genome instability, and conserved and divergent features of repair

Genome Stability: DNA Repair and Recombination describes the various mechanisms of repairing DNA damage by recombination, most notably the repair of chromosomal breaks. The text presents a definitive history of the evolution of molecular models of DNA repair, emphasizing current research. The book introduces the central players in recombination. An overview of the four major pathways of homologous recombinational repair is followed by a description of the several mechanisms of nonhomologous end-joining. Designed as a textbook for advanced undergraduate and graduate students with a molecular biology and genetics background, researchers and practitioners, especially in cancer biology, will also appreciate the book as a reference.

Since the establishment of the DNA structure researchers have been highly interested in the molecular basis of the inheritance of genes and of genetic disorders. Scientific investigations of the last two decades have shown that, in addition to oncogenic viruses and signalling pathways alterations, genomic instability is important in the development of cancer. This view is supported by the findings that aneuploidy, which results from chromosome instability, is one of the hallmarks of cancer cells. Chromosomal instability also underpins our fundamental principles of understanding tumourigenesis: It thought that cancer arises from the sequential acquisition of genetic alterations in specific genes. In this hypothesis, these rare genetic events represent rate-limiting ‘bottlenecks’ in the clonal evolution of a cancer, and pre-cancerous cells can evolve into neoplastic cells through the acquisition of somatic mutations. This book is written by international leading scientists in the field of genome stability. Chapters are devoted to genome stability and anti-cancer drug targets, histone modifications, chromatin factors, DNA repair, apoptosis and many other key areas of research. The chapters give insights into the newest development of the genome stability and human diseases and bring the current understanding of the mechanisms leading to chromosome instability and their potential for clinical impact to the reader.

An overview of the current systems biology-based knowledge and the experimental approaches for deciphering the biological basis of cancer.

"Genome Stability: DNA Repair and Recombination describes the various mechanisms of repairing DNA damage by recombination, most notably the repair of chromosomal breaks. The text presents a definitive history of the evolution of molecular models of DNA repair, emphasizing current research. The book introduces the central players in recombination. An overview of the four major pathways of homologous recombinational repair is followed by a description of the several mechanisms of nonhomologous end-joining. Designed as a textbook for advanced undergraduate and graduate students with a molecular biology and genetics background, researchers and practitioners, especially in cancer biology, will also appreciate the book as a reference"--

The human genome, as with the genome of most organisms, is comprised of various types of mobile genetic element derived repeats. Mobile genetic elements that mobilize by an RNA intermediate, include both autonomous and non-autonomous retrotransposons, and mobilize by a “copy and paste” mechanism that relies of the presence of a functional reverse transcriptase activity. The extent to which these different types of elements are actively mobilizing varies among organisms, as revealed with the advent of Next Generation DNA sequencing (NGS). To understand the normal and aberrant mechanisms that impact the mobility of these elements requires a more extensive understanding of how these elements interact with molecular pathways of the cell, including DNA repair, recombination and chromatin. In addition, epigenetic based-mechanisms can also influence the mobility of these elements, likely by transcriptional activation or repression in certain cell types. Studies regarding how mobile genetic elements interface and evolve with these pathways will rely on genomic studies from various model organisms. In addition, the mechanistic details of how these elements are regulated will continue to be elucidated with the use of genetic, biochemical, molecular, cellular, and bioinformatic approaches. Remarkably, the current understanding regarding the biology of these elements in the human genome, suggests these elements may impact developmental biology, including cellular differentiation, neuronal development, and immune function. Thus, aberrant changes in these molecular pathways may also impact disease, including neuronal degeneration, autoimmunity, and cancer.

Environmental stresses and metabolic by-products can severely affect the integrity of genetic information by inducing DNA damage and impairing genome stability. As a consequence, plant growth and productivity are irreversibly compromised. To overcome genotoxic injury, plants have evolved complex strategies relying on a highly efficient repair machinery that responds to sophisticated damage perception/signaling networks. The DNA damage signaling network contains several key components: DNA damage sensors, signal transducers, mediators, and effectors. Most of these components are common to other eukaryotes but some features are unique to the plant kingdom. ATM and ATR are well-conserved members of PIKK family, which amplify and transduce signals to downstream effectors. ATM primarily responds to DNA double strand breaks while ATR responds to various forms of DNA damage. The signals from the activated transducer kinases are transmitted to the downstream cell-cycle regulators, such as CHK1, CHK2, and p53 in many eukaryotes. However, plants have no homologue of CHK1, CHK2 nor p53. The finding of Arabidopsis transcription factor SOG1 that seems functionally but not structurally similar to p53 suggests that plants have developed unique cell cycle regulation mechanism. The double strand break repair, recombination repair, postreplication repair, and lesion bypass, have been investigated in several plants. The DNA double strand break, a most critical damage for organisms are repaired non-homologous end joining (NHEJ) or homologous recombination (HR) pathway. Damage on template DNA makes replication stall, which is processed by translesion synthesis (TLS) or error-free postreplication repair (PPR) pathway. Deletion of the error-prone TLS polymerase reduces mutation frequencies, suggesting PPR maintains the stalled replication fork when TLS is not available. Unveiling the regulation networks among these multiple pathways would be the next challenge to be completed. Some intriguing issues have been disclosed such as the cross-talk between DNA repair, senescence and pathogen response and the involvement of non-coding RNAs in global genome stability. Several studies have highlighted the essential contribution of chromatin remodeling in DNA repair DNA damage sensing, signaling and repair have been investigated in relation to environmental stresses, seed quality issues, mutation breeding in both model and crop plants and all these studies strengthen the idea that components of the plant response to genotoxic stress might represent tools to improve stress tolerance and field performance. This focus issue gives researchers the opportunity to gather and interact by providing Mini-Reviews, Commentaries, Opinions, Original Research and Method articles which describe the most recent advances and future perspectives in the field of DNA damage sensing, signaling and repair in plants. A comprehensive overview of the current progresses dealing with the genotoxic stress response in plants will be provided looking at cellular and molecular level with multidisciplinary approaches. This will hopefully bring together valuable information for both plant biotechnologists and breeders.