Molecular Physiology Of Insect Low Temperature Stress Responses

A metabolomic analysis of the freeze tolerant midge, Belgica antarctica, revealed that freezing increased a number of different polyols in whole-body extracts, incuding glycerol, mannitol, and erythritol. Freezing also increased alanine, asparagine, and glycine. In addition, the frozen midge larvae accumulated Krebs cycle intermediates, indicating that aerobic respiration is considerably slowed. Membrane involvement in freezing was not conclusively supported, although there was a reduction in oleic acid levels. A comparison of the metabolic responses of this midge to heat, freezing and desiccation revealed that freezing and desiccation produced similar results, supporting the hypothesis that the cellular response to these two stressors is related.

Low temperature is a major environmental constraint impacting the geographic distribution and seasonal activity patterns of insects. Written for academic researchers in environmental physiology and entomology, this book explores the physiological and molecular mechanisms that enable insects to cope with a cold environment and places these findings into an evolutionary and ecological context. An introductory chapter provides a primer on insect cold tolerance and subsequent chapters in the first section discuss the organismal, cellular and molecular responses that allow insects to survive in the cold despite their, at best, limited ability to regulate their own body temperature. The second section, highlighting the evolutionary and macrophysiological responses to low temperature, is especially relevant for understanding the impact of global climate change on insect systems. A final section translates the knowledge gained from the rest of the book into practical applications including cryopreservation and the augmentation of pest management strategies.

Abstract: As ectotherms with high surface area to volume ratio, insects are particularly susceptible to desiccation and low temperature stress. In this dissertation, I examine the molecular underpinnings of two facets of these stresses: rapid cold hardening and cryoprotective dehydration.

The study of insects at low temperature is a comparatively new field. Only recently has insect cryobiology begun to mature, as research moves from a descriptive approach to a search for underlying mechanisms at diverse levels of organization ranging from the gene and cell to ecological and evolutionary relationships. Knowledge of insect responses to low temperature is crucial for understanding the biology of insects living in seasonally varying habitats as well as in polar regions. It is not possible to precisely define low temperature. In the tropics exposure to 10-15°C may induce chill coma or death, whereas some insects in temperate and polar regions remain active and indeed even able to fly at O°C or below. In contrast, for persons interested in cryopreservation, low temperature may mean storage in liquid nitrogen at - 196°C. In the last decade, interest in adaptations of invertebrates to low temperature has risen steadily. In part, this book had its origins in a symposium on this subject that was held at the annual meeting of the Entomological Society of America in Louisville, Kentucky, USA in December, 1988. However, the emergence and growth of this area has also been strongly influenced by an informal group of investigators who met in a series of symposia held in Oslo, Norway in 1982, in Victoria, British Columbia, Canada in 1985 and in Cambridge, England in 1988. Another is scheduled for Binghamton, New York, USA (1990).

Advances in Insect Physiology publishes eclectic volumes containing important, comprehensive and in-depth reviews on all aspects of insect physiology. It is an essential reference source for invertebrate physiologists and neurobiologists, entomologists, zoologists and insect biochemists. First published in 1963, the serial is now edited by Steve Simpson (Oxford University, UK). More than 300 pages with contributions from the leading researchers in entomology Over 40 figures and illustrations combined Includes an in-depth review of the genetics of the honey bee Discusses the physiological diversity in insects

Insect physiology is currently undergoing a revolution with the increased application of molecular biological techniques to investigate the molecular mechanisms underlying the physiological responses to insect cells. Advances in Insect Physiology has instituted a commitment to the publication of high quality reviews on molecular biology and molecular genetics in areas where they provide an increased understanding of physiological processes in insects. Volume 25 contains increased coverage on the molecular biology of insect physiology.

The publication of the extensive seven-volume work Comprehensive Molecular Insect Science provided a complete reference encompassing important developments and achievements in modern insect science. One of the most swiftly moving areas in entomological and comparative research is molecular biology, and this volume, Insect Molecular Biology and Biochemistry, is designed for those who desire a comprehensive yet concise work on important aspects of this topic. This volume contains ten fully revised or rewritten chapters from the original series as well as five completely new chapters on topics such as insect immunology, insect genomics, RNAi, and molecular biology of circadian rhythms and circadian behavior. The topics included are key to an understanding of insect development, with emphasis on the cuticle, digestive properties, and the transport of lipids; extensive and integrated chapters on cytochrome P450s; and the role of transposable elements in the developmental processes as well as programmed cell death. This volume will be of great value to senior investigators, graduate students, post-doctoral fellows and advanced undergraduate research students. It can also be used as a reference for graduate courses and seminars on the topic. Chapters will also be valuable to the applied biologist or entomologist, providing the requisite understanding necessary for probing the more applied research areas related to insect control. Topics specially selected by the editor-in-chief of the original major reference work Fully revised and new contributions bring together the latest research in the rapidly moving fields of insect molecular biology and insect biochemistry, including coverage of development, physiology, immunity and proteomics Full-color provides readers with clear, useful illustrations to highlight important research findings

Biologists worldwide now speak the scientific language of molecular biology and use the same molecular tools. Interest is growing in the molecular biology of abiotic stress tolerance and modes of installing better tolerant mechanisms in crop plants. Current studies make plants capable of sustaining their yields even under stressful conditions. Further, this information may form the basis for its application in biotechnology and bioinformatics.

Our highly seasonal world restricts insect activity to brief portions of the year. This feature necessitates a sophisticated interpretation of seasonal changes and enactment of mechanisms for bringing development to a halt and then reinitiating it when the inimical season is past. The dormant state of diapause serves to bridge the unfavourable seasons, and its timing provides a powerful mechanism for synchronizing insect development. This book explores how seasonal signals are monitored and used by insects to enact specific molecular pathways that generate the diapause phenotype. The broad perspective offered here scales from the ecological to the molecular and thus provides a comprehensive view of this exciting and vibrant research field, offering insights on topics ranging from pest management, evolution, speciation, climate change and disease transmission, to human health, as well as analogies with other forms of invertebrate dormancy and mammalian hibernation.

Demystifies the genetic, biochemical, physiological, and molecular mechanisms underlying heat stress tolerance in plants Heat stress—when high temperatures cause irreversible damage to plant function or development—severely impairs the growth and yield of agriculturally important crops. As the global population mounts and temperatures continue to rise, it is crucial to understand the biochemical, physiological, and molecular mechanisms of thermotolerance to develop ‘climate-smart’ crops. Heat Stress Tolerance in Plants provides a holistic, cross-disciplinary survey of the latest science in this important field. Presenting contributions from an international team of plant scientists and researchers, this text examines heat stress, its impact on crop plants, and various mechanisms to modulate tolerance levels. Topics include recent advances in molecular genetic approaches to increasing heat tolerance, the potential role of biochemical and molecular markers in screening germplasm for thermotolerance, and the use of next-generation sequencing to unravel the novel genes associated with defense and metabolite pathways. This insightful book: Places contemporary research on heat stress in plants within the context of global climate change and population growth Includes diverse analyses from physiological, biochemical, molecular, and genetic perspectives Explores various approaches to increasing heat tolerance in crops of high commercial value, such as cotton Discusses the applications of plant genomics in the development of thermotolerant ‘designer crops’ An important contribution to the field, Heat Stress Tolerance in Plants is an invaluable resource for scientists, academics, students, and researchers working in fields of pulse crop biochemistry, physiology, genetics, breeding, and biotechnology.