Coiled Spring How Life Begins

Chapter 1: The Central Dogma of BiologyThe “central dogma”—that DNA, the heritable genetic material, is copied into RNA, which directs the synthesis of protein—is a basic tenet of life. How this idea guided important discoveries in developmental biology is described using examples of the Gurdon experiment, which proved that all cells in a frog contain the same genetic information; the nature of heritable mutations; and the Mangold-Spemann experiment, which showed that a specialized region of the frog embryo directs the formation of the nervous system. Chapter 2: Molecular Methods for Analyzing DevelopmentTechniques developed during the past 30 years have provided powerful tools for analyzing development. The most important of these—gene cloning, methods for showing gene activity in developing embryos, and methods for analyzing and manipulating gene activity—are described. Chapter 3: Establishing the Primary Axes of Fruit Fly EmbryosEstablishing a plan or pattern for development of the fertilized egg is the key event in producing a differentiated embryo with different tissue types. This process in the fruit fly is described using the ground-breaking work of Eric Wieschaus, Christiane Nusslein-Volhard, Gerd Jurgens, and Ed Lewis who found the genes that are required for normal development by looking for mutants in which development was abnormal. Chapter 4: Patterning Fly Appendages and EyesAssembly of the adult fruit fly during metamorphosis is the focus here, particularly the development of fly wings, legs, and eyes. These processes are explained by describing the small set of genes that define the primary axes of the wing, linking the formation of an adult structure to earlier events in embryonic development, and discussing the question of whether or not there are “master” genes that direct the formation of eyes. Chapter 5: Establishing the Primary Axes of Vertebrate EmbryosAlthough higher on the evolutionary scale, vertebrate embryos use many of the same genes as the fly embryo does to set up the primary body axes and tissue types. And even more remarkable is the fact that vertebrate genes involved in early embryonic development can replace their fruit fly counterparts in developing flies and vice versa. The experiments that revealed these astonishing facts and their implications are discussed. Chapter 6: Patterning Vertebrates Appendages and EyesHere again is the unexpected finding that genes involved in defining adult structures such as appendages and eyes are the same in vertebrates and flies. The evolutionary implications of the similarities of fly and vertebrate development are discussed, and the most recent common ancestor of flies and vertebrates is reconstructed. Chapter 7: Establishing the Primary Axes of Plant EmbryosUsing the mustard plant embryo as an example, important differences between plant and animal development are illustrated. The polarization of the plant embryo along the shoot-to-root axis, as well as radial organization, is shown using analysis of mutant plants that generate abnormal embryos. Similarities between plant and animal development are also discussed. Chapter 8: Patterning Plant AppendagesThe formation of the plant equivalent of appendages—flowers, fruits, and leaves—are described. Topics include: how flower buds develop into four basic organ types, Goethe’s inference that all organs of the flower are modified forms of leaves (he was right!), and the finding that while very different genes in plants and animals control formation of flat structures such as leaves or wings, these genes work by surprisingly similar mechanisms. Chapter 9: The Future of Biology and ManWe are very rapidly making progress in understanding how genes control development and other human characteristics. The social implications of these discoveries—how we think of ourselves as humans and how these discoveries can change our nature—are considered using topics such as the Human Genome Project, which is determining the complete genetic blueprint of humans, the implications of our newfound knowledge of the genetics of human disease and health, and genetic engineering of plants and animals. How the world of science fiction views these topics is also considered. BioboxesLandmark progress in science is made by pioneering individuals. Those responsible for some of the key discoveries in developmental biology are highlighted in “Bioboxes” that appear throughout the text. These scientists represent the human side of the wonderful discoveries described in this book. John Gurdon Hilde Mangold Johann Wolfgang von Goethe Ed Lewis Christiane Nusslein-Volhard Eric Wieschaus Mike Levine Sean Carroll Antonio Garcia-Bellido Gary Struhl Matthew Scott William McGinnis Cliff Tabin Gerd Jurgens Elliott Meyerowitz Enrico Coen Marty YanofskyBier, Ethan is the author of 'Coiled Spring How Life Begins', published 2000 under ISBN 9780879695637 and ISBN 0879695633.