Dna Deoxyribonucleic Acid Recombination Interactions And Repair

DNA: Recombination, Interactions and Repair presents the result of the proceedings of the FEBS Symposium on DNA, which focuses on DNA recombination in vivo and in vitro, DNA interactions, and DNA repair. This book presents problems involving topics on DNA that have been studied intensively using methodological approaches and developed techniques for cloning, physical mapping, and sequencing of DNA. This text also notes that this approach has provided a basis for further genetic studies at the molecular level. The problems related to the genetic complexity of higher organisms and the relationships between the structure of genetic material and the regulation of expression of genetic information, as well as genetic engineering of micro-organisms, which become amenable to experimental investigation, are also presented in this text. This book notes that these problems are closely associated with endeavors to understand the molecular foundations of living processes to create a rational basis for treating genetic and viral diseases. This text will be a valuable source of information for students studying in the field of genetics, especially those conducting extensive research on DNA.

This book is a comprehensive review of the detailed molecular mechanisms of and functional crosstalk among the replication, recombination, and repair of DNA (collectively called the "3Rs") and the related processes, with special consciousness of their biological and clinical consequences. The 3Rs are fundamental molecular mechanisms for organisms to maintain and sometimes intentionally alter genetic information. DNA replication, recombination, and repair, individually, have been important subjects of molecular biology since its emergence, but we have recently become aware that the 3Rs are actually much more intimately related to one another than we used to realize. Furthermore, the 3R research fields have been growing even more interdisciplinary, with better understanding of molecular mechanisms underlying other important processes, such as chromosome structures and functions, cell cycle and checkpoints, transcriptional and epigenetic regulation, and so on. This book comprises 7 parts and 21 chapters: Part 1 (Chapters 1–3), DNA Replication; Part 2 (Chapters 4–6), DNA Recombination; Part 3 (Chapters 7–9), DNA Repair; Part 4 (Chapters 10–13), Genome Instability and Mutagenesis; Part 5 (Chapters 14–15), Chromosome Dynamics and Functions; Part 6 (Chapters 16–18), Cell Cycle and Checkpoints; Part 7 (Chapters 19–21), Interplay with Transcription and Epigenetic Regulation. This volume should attract the great interest of graduate students, postdoctoral fellows, and senior scientists in broad research fields of basic molecular biology, not only the core 3Rs, but also the various related fields (chromosome, cell cycle, transcription, epigenetics, and similar areas). Additionally, researchers in neurological sciences, developmental biology, immunology, evolutionary biology, and many other fields will find this book valuable.

Reviews the latest research in the field for researchers and clinicians. After a general introduction to DNA base excision repair, chapters cover uracil DNA glycosylases, repair of oxidized purines in DNA, mammalian mismatch-specific DNA glycosylases, repair of apurinic/apyrimidic sites in DNA by AP endonucleases, mutagenesis of abasic sites, a pro

There has been a sea change in how we view genetic recombination. When germ cells are produced in higher organisms, genetic recombination assures the proper segregation of like chromosomes. In the course of that process, called meiosis, recombination not only assures segregation of one chromosome of each type to progeny germ cells, but also further shuffles the genetic deck, contributing to the unique inheritance of individuals. In a nutshell, that is the classical view of recombination. We have also known for many years that in bacteria recombination plays a role in horizontal gene transfer and in replication itself, the latter by establishing some of the replication forks that are the structural scaffolds for copying DNA. In recent years, however, we have become increasingly aware that replication, which normally starts without any help from recombination, is a vulnerable process that frequently leads to broken DNA. The enzymes of recombination play a vital role in the repair of those breaks. The recombination enzymes can function via several different pathways that mediate the repair of breaks, as well as restoration of replication forks that are stalled by other kinds of damage to DNA. Thus, to the classical view of recombination as an engine of inheritance we must add the view of recombination as a vital housekeeping function that repairs breaks suffered in the course of replication. We have also known for many years that genomic instability--including mutations, chromosomal rearrangements, and aneuploidy--is a hallmark of cancer cells. Although genomic instability has many contributing causes, including faulty replication, there are many indications that recombination, faulty or not, contributes to genome instability and cancer as well. The (Nas colloquium) Links Between Recombination and Replication: Vital Roles of Recombination was convened to broaden awareness of this evolving area of research. Papers generated by this colloquium are published here. To encourage the desired interactions of specialists, we invited some contributions that deal only with recombination or replication in addition to contributions on the central thesis of functional links between recombination and replication. To aid the nonspecialist and specialist alike, we open the set of papers with a historical overview by Michael Cox and we close the set with a commentary on the meeting and the field by Andrei Kuzminov.

Genetic recombination, in the broadest sense, can be defined as any process in which DNA sequences interact and undergo a transfer of information, producing new “recombinant” sequences that contain information from each of the original molecules. All organisms have the ability to carry out recombination, and this striking universality speaks to the essential role recombination plays in a variety of biological processes fundamentally important to the maintenance of life. Such processes include DNA repair, regulation of gene expression, disease etiology, meiotic chromosome segregation, and evolution. One important aspect of recombination is that it typically occurs only between sequences that display a high degree of sequence identity. The stringent requirement for homology helps to ensure that, under normal circumstances, a cell is protected from deleterious rearrangements since a swap of genetic information between two nearly identical sequences is not expected to dramatically alter a genome. Recombination between dissimilar sequences, which does happen on occasion, may have such harmful consequences as chromosomal translocations, deletions, or inversions. For many organisms, it is also important that recombination rates are not too high lest the genome become destabilized. Curiously, certain organisms, such as the trypanosome parasite, actually use a high rate of recombination at a particular locus in order to switch antigen expression continually and evade the host immune system effectively.

Genomic instability is a major threat to living organisms. To counteract the damaging effects posed by endogenous and environmental agents, such as chemicals or radiation, micro-organisms devote several percent of their genome to encode proteins that function in the repair and recombination of DNA. For many years, a relatively small group of scientists have carefully delineated the molecular mechanisms of these repair processes, using the simplest model systems available, namely Escherichia coli and Saccharomyces cerevisiae. These studies, which until recently had only moderate impact outside of the field, now provide the cornerstone for exciting new research into analogous processes in human cells. The reason for this is the revelation that the biochemical pathways for the accurate replication, repair and recombination of DNA have been conserved through evolution.