[
2013]
One of the central aims of modern biology is to elucidate the mechanisms leading to the complex structures of organisms. Using the information inherent in the one-dimensional nucleotide sequence of the genome, cleavage divisions of the fertilized egg, with all the associated genetic and epigenetic regulatory steps, generates a specific three-dimensional pattern of differentiated cells. Anensuing series of dynamic processes finally results in a functional organism with many complex structures and phenotypes. Understanding the genetic and molecularbasis of embryonic and postembryonic patterning during development has been a central field of research since the 1970s, and nematodes have been at the forefront of this research.
The world of modern biology is unified by genetics. Genetic approaches have the ability to transcend species and provide cross-links between fields for several reasons. First, is the fact that all species are evolutionarily related. Thus, distinct species have similar gene function, and DNA sequence homology can be found between even distantly related species. Indeed, DNA sequence homology is used as a metric device to determine evolutionary relationships among species. Second, molecular genetic manipulation changes both the genotype and phenotype of an organism. Such manipulations represent an extremely fine-scale tool for dissection of the underlying biochemistry, physiology, anatomy, and development of an individual species. Because virtually any gene can be manipulated at will in many species, a dedicated approach can lead to an unraveling of the relationship between genotype and phenotype for almost any gene in these species.....
[
2003]
Since the publication of the first genetic research paper on Caenorhabditis elegans (C. elegans for short) in 1974, this microscopic, free-living nematode has become a popular model organism to study development, neurobiology, and other biological problems. The ability to do powerful genetics has been the most critical reason why studies using this organism have made enormous contributions to basic biology and medical science. Therefore, C. elegans genetics should be part of any modern genetic education. In this chapter, we describe some of the unique properties of C. elegans that makes it an exceptional organism for genetic and molecular biological research. Some important genetic tools and methodologies developed by C. elegans researchers will also be introduced. We aim to connect the fundamental principles of genetics as described in early chapters with practical applications of these principles in actual research. We have chosen a few genetic pathways and biological problems as examples for illustrating the logic behind the genetic analyses and for introducing some commonly practiced strategies and methods. We do not hesitate to introduce some of the most advanced and up-to-date methods and approaches, including those developed since the genome sequence was determined in 1998. We believe today's students can go right into the heart of present research after learning the basic principle of Genetics (see the early chapters of this book) and molecular biology. In fact, in many C. elegans laboratories, undergraduate students are doing a wide variety of experiments using the genetic techniques