Once considered merely `selfish' or `parasitic' DNA, transposable elements are today recognized as being of major biological significance. Not only are these elements a major source of mutation, they have contributed both directly and indirectly to the evolution of genome structure and function. On October 8-10, 1999, 100 molecular biologists and evolutionists representing 11 countries met on the campus of The University of Georgia in Athens for the inaugural Georgia Genetics Symposium. The topics of presentations ranged from how the elements themselves have evolved to the impact transposable elements have had on the evolution of their host genomes. The papers in this volume therefore represent state-of-the-art thinking, by leading world experts in the field, on the evolutionary significance of transposable elements.
During the last 50 years, the perception oftransposable elements (TEs) has changed considerably from selfish DNA to sequences that may contribute significantly to genome function and evolution. The recent increased interest in TEs is based on the realization that they are a major genetic component (at least 10--20%) of all organisms and a major contributor to the mutation process. It is currently estimated that 70--80% of spontaneous mutations are the result of TE-mediated insertions, deletions, or chromosomal rearrangements. Thus, it seems at least plausible that TEs may playa significant role in the adaptation and evolution of natural populations and species. The ubiquity of TEs suggests that they are an old component of genomes which have been vertically transmitted through generations over evolutionary time. However, detailed analyses carried out over the last 20 years have revealed several unusual features of TE evolution: (i) TEs can be horizontally transferred between species; (ii) TE evolutionary rates can be dramatically increased by specific inactivation processes, such as the RIP (Repeat Induced Point mutation) mechanism in fungi; (iii) TEs can influence the regulation of other TEs by insertion or deletion; (iv) different classes of TEs in even distantly related species can be remarkably similar in both structure and function.
The transposable genetic elements, or transposons, as they are now known, have had a tumultuous history. Discovered in the mid-20th century by Barbara McClintock, they were initially received with puzzlement. When their genomic abundance began to be apparent, they were categorized as "junk DNA" and acquired the label of parasites. Expanding understanding of gene and genome organization has revealed the profound extent of their impact on both. Plant Transposons and Genome Dynamics in Evolution captures and distills the voluminous research literature on plant transposable elements and seeks to assemble the big picture of how transposons shape gene structure and regulation, as well as how they sculpt genomes in evolution. Individual chapters provide concise overviews of the many flavors of plant transposons and of their roles in gene creation, gene regulation, development, genome evolution, and organismal speciation, as well as of their epigenetic regulation. This volume is essential reading for anyone working in plant genetics, epigenetics, or evolutionary biology.
An exploration of the raw power of genetic material to refashion itself to any purpose... Virtually all organisms contain multiple mobile DNAs that can move from place to place, and in some organisms, mobile DNA elements make up a significant portion of the genome. Mobile DNA III provides a comprehensive review of recent research, including findings suggesting the important role that mobile elements play in genome evolution and stability. Editor-in-Chief Nancy L. Craig assembled a team of multidisciplinary experts to develop this cutting-edge resource that covers the specific molecular mechanisms involved in recombination, including a detailed structural analysis of the enzymes responsible presents a detailed account of the many different recombination systems that can rearrange genomes examines the tremendous impact of mobile DNA in virtually all organisms Mobile DNA III is valuable as an in-depth supplemental reading for upper level life sciences students and as a reference for investigators exploring new biological systems. Biomedical researchers will find documentation of recent advances in understanding immune-antigen conflict between host and pathogen. It introduces biotechnicians to amazing tools for in vivo control of designer DNAs. It allows specialists to pick and choose advanced reviews of specific elements and to be drawn in by unexpected parallels and contrasts among the elements in diverse organisms. Mobile DNA III provides the most lucid reviews of these complex topics available anywhere.
Documents the remarkable mobility of DNA in procaryotic and eucaryotic genomes: the ability of various DNA segments to move to new sites, to invert, and to undergo deletion or amplification, generally without the extensive DNA sequence homology needed for classical recombination. Seventy contributors explore the mechanisms of these rearrangements, how they are regulated, their biological consequences, and their potential use as research tools. For students and researchers of molecular genetics. Annotation copyrighted by Book News, Inc., Portland, OR
Life history theory seeks to explain the evolution of the major features of life cycles by analyzing the ecological factors that shape age-specific schedules of growth, reproduction, and survival and by investigating the trade-offs that constrain the evolution of these traits. Although life history theory has made enormous progress in explaining the diversity of life history strategies among species, it traditionally ignores the underlying proximate mechanisms. This novel book argues that many fundamental problems in life history evolution, including the nature of trade-offs, can only be fully resolved if we begin to integrate information on developmental, physiological, and genetic mechanisms into the classical life history framework. Each chapter is written by an established or up-and-coming leader in their respective field; they not only represent the state of the art but also offer fresh perspectives for future research. The text is divided into 7 sections that cover basic concepts (Part 1), the mechanisms that affect different parts of the life cycle (growth, development, and maturation; reproduction; and aging and somatic maintenance) (Parts 2-4), life history plasticity (Part 5), life history integration and trade-offs (Part 6), and concludes with a synthesis chapter written by a prominent leader in the field and an editorial postscript (Part 7).
During the last 50 years, the perception oftransposable elements (TEs) has changed considerably from selfish DNA to sequences that may contribute significantly to genome function and evolution. The recent increased interest in TEs is based on the realization that they are a major genetic component (at least 10--20%) of all organisms and a major contributor to the mutation process. It is currently estimated that 70--80% of spontaneous mutations are the result of TE-mediated insertions, deletions, or chromosomal rearrangements. Thus, it seems at least plausible that TEs may playa significant role in the adaptation and evolution of natural populations and species. The ubiquity of TEs suggests that they are an old component of genomes which have been vertically transmitted through generations over evolutionary time. However, detailed analyses carried out over the last 20 years have revealed several unusual features of TE evolution: (i) TEs can be horizontally transferred between species; (ii) TE evolutionary rates can be dramatically increased by specific inactivation processes, such as the RIP (Repeat Induced Point mutation) mechanism in fungi; (iii) TEs can influence the regulation of other TEs by insertion or deletion; (iv) different classes of TEs in even distantly related species can be remarkably similar in both structure and function.
"This new volume provides an up-to-date understanding of the numerous classes of plant transposable elements, the mobile units of DNA that comprise large portions of plant genomes, an important contributor for gene and genome evolution. Transposable elements (TEs) are major components of large plant genomes and main drivers of genome evolution, known to produce a wide variety of changes in plant gene expression and function. This book, Plant Transposable Elements: Biology and Biotechnology, provides a systematic interpretation of protocols designed to characterize TEs and their biotechnological roles. The chapters explore the role of TEs in plant development, their architecture, their epigenetic regulation, their use in DNA repair, their evolution and speciation, while highlighting their importance in the approaching epoch of climate change. It discusses the applications of the transposons in genome editing and their biology, classification, structure, functions, and evolution. The volume begins with introduction of transposable elements (TEs), covering their introduction, classification, and transposition. It delves into protocols designed to characterize TEs and their biotechnological applications. This section looks at computational approaches for prediction and analysis, retro-transposon capture sequencing, and more. The section on transposon biology focuses on its role in plant development and as natural genetic engineers of genome mutation, evolution, and speciation. The book looks further into transposon applications in genome editing, exploring tagging and mutagenesis, genome engineering, and more. The last chapter uses the example of Oryza sativa to elucidate on the classification, structure, function, and evolution of transposable elements. This comprehensive volume is a valuable comprehensive resource for researchers, faculty, and students in biology, biotechnology, genetics, and botany and plant science."--
Repetitive DNA is ubiquitous in eukaryotic genomes, and, in many species, comprises the bulk of the genome. Repeats include transposable elements that can self-mobilize and disperse around the genome, and tandemly-repeated satellite DNAs that increase in copy number due to replication slippage and unequal crossing over. Despite their abundance, repetitive DNA is often ignored in genomic studies due to technical challenges in their identification, assembly, and quantification. New technologies and methods are now providing the unprecedented power to analyze repetitive DNAs across diverse taxa. Repetitive DNA is of particular interest because it can represent distinct modes of genome evolution. Some repetitive DNA forms essential genome structures, such as telomeres and centromeres, which are required for proper chromosome maintenance and segregation, whereas others form piRNA clusters that regulate transposable elements; thus, these elements are expected to evolve under purifying selection. In contrast, other repeats evolve selfishly and produce genetic conflicts with their host species that drive adaptive evolution of host defense systems. However, the majority of repeats likely accumulate in eukaryotes in the absence of selection due to mechanisms of transposition and unequal crossing over. Even these neutral repeats may indirectly influence genome evolution as they reach high abundance. In this Special Issue, the contributing authors explore these questions from a range of perspectives.
In the summer of 1992 a distinguished group of molecular, population and evolutionary geneticists assembled on the campus of the University of Georgia in Athens, USA to discuss the relevance of their research to the role played by transposable elements (TEs) in evolution. The meeting consisted of a series of informal discussions of issues brought up in papers written by the participants and distributed among them prior to the meeting. These papers and the transcripts of the ensuing discussions are presented in this volume.
