Download or read book The Role of Stress induced Mutagenesis in Adaptation written by Dustin Phipps and published by . This book was released on 2014 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Stress Induced Mutagenesis written by David Mittelman and published by Springer Science & Business Media. This book was released on 2013-03-12 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt: The discovery of stress-induced mutagenesis has changed ideas about mutation and evolution, and revealed mutagenic programs that differ from standard spontaneous mutagenesis in rapidly proliferating cells. The stress-induced mutations occur during growth-limiting stress, and can include adaptive mutations that allow growth in the otherwise growth-limiting environment. The stress responses increase mutagenesis specifically when cells are maladapted to their environments, i.e. are stressed, potentially accelerating evolution then. The mutation mechanism also includes temporary suspension of post-synthesis mismatch repair, resembling mutagenesis characteristic of some cancers. Stress-induced mutation mechanisms may provide important models for genome instability underlying some cancers and genetic diseases, resistance to chemotherapeutic and antibiotic drugs, pathogenicity of microbes, and many other important evolutionary processes. This book covers pathways of stress-induced mutagenesis in all systems. The principle focus is mammalian systems, but much of what is known of these pathways comes from non-mammalian systems.
Download or read book Mechanism of Rapid Adaptation Under Selection written by Emiko Beatriz Sano and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Time-dependent accumulation of mutants in several genetic systems has led to the controversial conclusion that bacteria possess a mechanism to elevate general mutagenesis in response to stress. In particular, extensive study of the Cairns system has kept the controversy alive despite theoretical analysis suggesting that general mutagenesis is counter-productive. In the Cairns system, a lac mutant strain gives rise to Lac revertant colonies that accumulate above a non-growing lawn over a week. Two conflicting models explain this behavior. The Stress-Induced Mutagenesis model proposes that cells have a mechanism that creates genome-wide mutations during growth limitation that may relieve the stress. Most mutations are attributed to action of the error-prone Pol IV polymerase during recombination-dependent double-stranded break repair in non-growing cells. We have directly tested this model by measuring mutation rates during non-selective growth (the only condition under which a true mutation rate can be measured). Cell functions that are proposed to change in response to stress (SOS, Pol IV and recombination) and cause mutagenesis are given or removed from growing cultures. We find that none of these factors affect mutation rate in growing cells. In addition, we find that vast (non-physiological) over-expression of Pol IV causes mutagenesis that shows no dependence on recombination. Results are conflicting with predictions of the Stress-Induced Mutagenesis model. Results are explained by the alternative Growth-Under-Selection model in which pre-existing small-effect mutations initiate slow-growing clones under selection. Within developing colonies, secondary genetic improvements occur without enhanced mutagenesis. These mutations are made more likely by the increasing number of potential targets for mutations within a growing colony. We provide evidence that revertant colonies appearing under selection are initiated by pre-existing cells with an amplification of the mutant lacgene. By killing these pre-existing cells, we prevent appearance of revertant colonies on selective plates. This demonstrates that revertant number is determined before selection cannot be created in response to stress.
Download or read book Stress and Environmental Regulation of Gene Expression and Adaptation in Bacteria written by Frans J. de Bruijn and published by John Wiley & Sons. This book was released on 2016-07-13 with total page 1472 pages. Available in PDF, EPUB and Kindle. Book excerpt: Bacteria in various habitats are subject to continuously changing environmental conditions, such as nutrient deprivation, heat and cold stress, UV radiation, oxidative stress, dessication, acid stress, nitrosative stress, cell envelope stress, heavy metal exposure, osmotic stress, and others. In order to survive, they have to respond to these conditions by adapting their physiology through sometimes drastic changes in gene expression. In addition they may adapt by changing their morphology, forming biofilms, fruiting bodies or spores, filaments, Viable But Not Culturable (VBNC) cells or moving away from stress compounds via chemotaxis. Changes in gene expression constitute the main component of the bacterial response to stress and environmental changes, and involve a myriad of different mechanisms, including (alternative) sigma factors, bi- or tri-component regulatory systems, small non-coding RNA’s, chaperones, CHRIS-Cas systems, DNA repair, toxin-antitoxin systems, the stringent response, efflux pumps, alarmones, and modulation of the cell envelope or membranes, to name a few. Many regulatory elements are conserved in different bacteria; however there are endless variations on the theme and novel elements of gene regulation in bacteria inhabiting particular environments are constantly being discovered. Especially in (pathogenic) bacteria colonizing the human body a plethora of bacterial responses to innate stresses such as pH, reactive nitrogen and oxygen species and antibiotic stress are being described. An attempt is made to not only cover model systems but give a broad overview of the stress-responsive regulatory systems in a variety of bacteria, including medically important bacteria, where elucidation of certain aspects of these systems could lead to treatment strategies of the pathogens. Many of the regulatory systems being uncovered are specific, but there is also considerable “cross-talk” between different circuits. Stress and Environmental Regulation of Gene Expression and Adaptation in Bacteria is a comprehensive two-volume work bringing together both review and original research articles on key topics in stress and environmental control of gene expression in bacteria. Volume One contains key overview chapters, as well as content on one/two/three component regulatory systems and stress responses, sigma factors and stress responses, small non-coding RNAs and stress responses, toxin-antitoxin systems and stress responses, stringent response to stress, responses to UV irradiation, SOS and double stranded systems repair systems and stress, adaptation to both oxidative and osmotic stress, and desiccation tolerance and drought stress. Volume Two covers heat shock responses, chaperonins and stress, cold shock responses, adaptation to acid stress, nitrosative stress, and envelope stress, as well as iron homeostasis, metal resistance, quorum sensing, chemotaxis and biofilm formation, and viable but not culturable (VBNC) cells. Covering the full breadth of current stress and environmental control of gene expression studies and expanding it towards future advances in the field, these two volumes are a one-stop reference for (non) medical molecular geneticists interested in gene regulation under stress.
Download or read book Immunology and Evolution of Infectious Disease written by Steven A. Frank and published by Princeton University Press. This book was released on 2002-07-21 with total page 364 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publisher Description
Download or read book Bacterial Stress Responses written by Gisela Storz and published by American Society for Microbiology Press. This book was released on 2010-11-16 with total page 1167 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gain new insight on utilizing bacterial stress responses to better combat bacterial infection with antibiotics and improve biotechnology. • Reviews the vast number of new findings that have greatly advanced the understanding of bacterial stress responses in the past 10 years. • Explores general regulatory principles, including the latest findings from genomics studies, including new research findings on both specific and general stress responses. • Details how stress responses affect the interactions between bacteria and host cells and covers bacterial stress responses in different niches and communities, with an emphasis on extreme environments.
Download or read book Starvation in Bacteria written by S. Kjelleberg and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concerted efforts to study starvation and survival of nondifferentiating vegeta tive heterotrophic bacteria have been made with various degrees of intensity, in different bacteria and contexts, over more than the last 30 years. As with bacterial growth in natural ecosystem conditions, these research efforts have been intermittent, with rather long periods of limited or no production in between. While several important and well-received reviews and proceedings on the topic of this monograph have been published during the last three to four decades, the last few years have seen a marked increase in reviews on starvation survival in non-spore-forming bacteria. This increase reflects a realization that the biology of bacteria in natural conditions is generally not that of logarithmic growth and that we have very limited information on the physiology of the energy-and nutrient-limited phases of the life cyde of the bacterial cello The growing interest in nongrowing bacteria also sterns from the more recent advances on the molecular basis of the starvation-induced nongrowing bacterial cello The identification of starvation-specific gene and protein re sponders in Escherichia coli as weIl as other bacterial species has provided molecular handles for our attempts to decipher the "differentiation-like" responses and programs that nondifferentiating bacteria exhibit on nutrient limited growth arrest. Severallaboratories have contributed greatly to the progress made in life after-log research.
Download or read book Genetics of Adaptation written by Rodney Mauricio and published by Springer Science & Business Media. This book was released on 2005-07-20 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: An enduring controversy in evolutionary biology is the genetic basis of adaptation. Darwin emphasized "many slight differences" as the ultimate source of variation to be acted upon by natural selection. In the early 1900’s, this view was opposed by "Mendelian geneticists", who emphasized the importance of "macromutations" in evolution. The Modern Synthesis resolved this controversy, concluding that mutations in genes of very small effect were responsible for adaptive evolution. A decade ago, Allen Orr and Jerry Coyne reexamined the evidence for this neo-Darwinian view and found that both the theoretical and empirical basis for it were weak. Orr and Coyne encouraged evolutionary biologists to reexamine this neglected question: what is the genetic basis of adaptive evolution? In this volume, a new generation of biologists have taken up this challenge. Using advances in both molecular genetic and statistical techniques, evolutionary geneticists have made considerable progress in this emerging field. In this volume, a diversity of examples from plant and animal studies provides valuable information for those interested in the genetics and evolution of complex traits.
Download or read book Plant Mutation Breeding and Biotechnology written by Q. Y. Shu and published by CABI. This book was released on 2012 with total page 612 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: This book presents contemporary information on mutagenesis in plants and its applications in plant breeding and research. The topics are classified into sections focusing on the concepts, historical development and genetic basis of plant mutation breeding (chapters 1-6); mutagens and induced mutagenesis (chapters 7-13); mutation induction and mutant development (chapters 14-23); mutation breeding (chapters 24-34); or mutations in functional genomics (chapters 35-41). This book is an essential reference for those who are conducting research on mutagenesis as an approach to improving or modifying a trait, or achieving basic understanding of a pathway for a trait --.
Download or read book Stress Inducible Cellular Responses written by U. Feige and published by Springer Science & Business Media. This book was released on 1996-09-26 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book will deal with heat shock proteins and more generally with stress-related inducible gene expression as a pleiotropic adaptive response to stress. It presents a textbook-like overview of the field not only to heat shock experts, but to physiologists, pharmacologists, physicians, neuropsychologists and others as well. It is intended to be a state-of-the-art and perspective book rather than an up-to-date presentation of recent data. It should provide a basis for new experimental approaches to fields at the edge of the classical heat shock field. Drugs, UV irradiation and environmental toxics will considered as important modulators of the stress response. Radical scavengers such as superoxide dismutases and inducible regulatory proteins of metallic ion status such as ferritin as well as immunophilins and protein disulfide isomerases will be considered within the frame of stress proteins. The potential practical applications of heat shock proteins in toxicology and medicine for the diagnosis, prognosis and eventually therapy of clinical conditions associated with an increased oxidative burden will be outlined. The role of heat shock proteins in the modulation of immune responses will also be included. The book considers heat shock from a broad perspective including fields for which heat-shock may become of importance in the very near future such as cellular responses to environmental stresses and complex stress responses under specific conditions. It was also felt timely to incorporate a whole section on medical and technological applications of stress proteins.
Download or read book Induced Plant Mutations in the Genomics Era written by Q. Y. Shu and published by . This book was released on 2009 with total page 458 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Yeast Stress Responses written by Stefan Hohmann and published by Springer Science & Business Media. This book was released on 2007-10-23 with total page 398 pages. Available in PDF, EPUB and Kindle. Book excerpt: Every cell has developed mechanisms to respond to changes in its environment and to adapt its growth and metabolism to unfavorable conditions. The unicellular eukaryote yeast has long proven as a particularly useful model system for the analysis of cellular stress responses, and the completion of the yeast genome sequence has only added to its power This volume comprehensively reviews both the basic features of the yeast genral stress response and the specific adapations to different stress types (nutrient depletion, osmotic and heat shock as well as salt and oxidative stress). It includes the latest findings in the field and discusses the implications for the analysis of stress response mechanisms in higher eukaryotes as well.
Download or read book Environmental Stress Adaptation and Evolution written by K. Bijlsma and published by Birkhäuser. This book was released on 2013-03-08 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: Most organisms and populations have to cope with hostile environments, threatening their existence. Their ability to respond phenotypically and genetically to these challenges and to evolve adaptive mechanisms is, therefore, crucial. The contributions to this book aim at understanding, from a evolutionary perspective, the impact of stress on biological systems. Scientists, applying different approaches spanning from the molecular and the protein level to individuals, populations and ecosystems, explore how organisms adapt to extreme environments, how stress changes genetic structure and affects life histories, how organisms cope with thermal stress through acclimation, and how environmental and genetic stress induce fluctuating asymmetry, shape selection pressure and cause extinction of populations. Finally, it discusses the role of stress in evolutionary change, from stress induced mutations and selection to speciation and evolution at the geological time scale. The book contains reviews and novel scientific results on the subject. It will be of interest to both researchers and graduate students and may serve as a text for graduate courses.
Download or read book Biotechnologies for Plant Mutation Breeding written by Joanna Jankowicz-Cieslak and published by Springer. This book was released on 2016-12-08 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is open access under a CC BY-NC 2.5 license. This book offers 19 detailed protocols on the use of induced mutations in crop breeding and functional genomics studies, which cover topics including chemical and physical mutagenesis, phenotypic screening methods, traditional TILLING and TILLING by sequencing, doubled haploidy, targeted genome editing, and low-cost methods for the molecular characterization of mutant plants that are suitable for laboratories in developing countries. The collection of protocols equips users with the techniques they need in order to start a program on mutation breeding or functional genomics using both forward and reverse-genetic approaches. Methods are provided for seed and vegetatively propagated crops (e.g. banana, barley, cassava, jatropha, rice) and can be adapted for use in other species.
Download or read book Microbial Evolution and Co Adaptation written by Institute of Medicine and published by National Academies Press. This book was released on 2009-05-10 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dr. Joshua Lederberg - scientist, Nobel laureate, visionary thinker, and friend of the Forum on Microbial Threats - died on February 2, 2008. It was in his honor that the Institute of Medicine's Forum on Microbial Threats convened a public workshop on May 20-21, 2008, to examine Dr. Lederberg's scientific and policy contributions to the marketplace of ideas in the life sciences, medicine, and public policy. The resulting workshop summary, Microbial Evolution and Co-Adaptation, demonstrates the extent to which conceptual and technological developments have, within a few short years, advanced our collective understanding of the microbiome, microbial genetics, microbial communities, and microbe-host-environment interactions.
Download or read book Abiotic Stress Response in Plants written by Arun Shanker and published by BoD – Books on Demand. This book was released on 2011-08-29 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plants, unlike animals, are sessile. This demands that adverse changes in their environment are quickly recognized, distinguished and responded to with suitable reactions. Drought, heat, cold and salinity are among the major abiotic stresses that adversely affect plant growth and productivity. In general, abiotic stress often causes a series of morphological, physiological, biochemical and molecular changes that unfavorably affect plant growth, development and productivity. Drought, salinity, extreme temperatures (cold and heat) and oxidative stress are often interrelated; these conditions singularly or in combination induce cellular damage. To cope with abiotic stresses, of paramount significance is to understand plant responses to abiotic stresses that disturb the homeostatic equilibrium at cellular and molecular level in order to identify a common mechanism for multiple stress tolerance. This multi authored edited compilation attempts to put forth an all-inclusive biochemical and molecular picture in a systems approach wherein mechanism and adaptation aspects of abiotic stress are dealt with. The chief objective of the book hence is to deliver state of the art information for comprehending the effects of abiotic stress in plants at the cellular level.
Download or read book Crop Stress and its Management Perspectives and Strategies written by B. Venkateswarlu and published by Springer Science & Business Media. This book was released on 2011-11-22 with total page 617 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crops experience an assortment of environmental stresses which include abiotic viz., drought, water logging, salinity, extremes of temperature, high variability in radiation, subtle but perceptible changes in atmospheric gases and biotic viz., insects, birds, other pests, weeds, pathogens (viruses and other microbes). The ability to tolerate or adapt and overwinter by effectively countering these stresses is a very multifaceted phenomenon. In addition, the inability to do so which renders the crops susceptible is again the result of various exogenous and endogenous interactions in the ecosystem. Both biotic and abiotic stresses occur at various stages of plant development and frequently more than one stress concurrently affects the crop. Stresses result in both universal and definite effects on plant growth and development. One of the imposing tasks for the crop researchers globally is to distinguish and to diminish effects of these stress factors on the performance of crop plants, especially with respect to yield and quality of harvested products. This is of special significance in view of the impending climate change, with complex consequences for economically profitable and ecologically and environmentally sound global agriculture. The challenge at the hands of the crop scientist in such a scenario is to promote a competitive and multifunctional agriculture, leading to the production of highly nourishing, healthy and secure food and animal feed as well as raw materials for a wide variety of industrial applications. In order to successfully meet this challenge researchers have to understand the various aspects of these stresses in view of the current development from molecules to ecosystems. The book will focus on broad research areas in relation to these stresses which are in the forefront in contemporary crop stress research.
