Introduction to C. elegans

Abstract

I. THE BIOLOGICAL MODEL In 1965, Sydney Brenner settled on Caenorhabditis elegans as a model organism to study animal development and behavior for reasons that are now well known (Brenner 1973Brenner 1988). This soil nematode offered great potential for genetic analysis, partly because of its rapid (3-day) life cycle, small size (1.5-mm-long adult), and ease of laboratory cultivation. One might imagine how the ability to grow thousands of animals on a single petri dish seeded with a lawn of Escherichia coli as the food source had a certain appeal to a bacteriophage geneticist such as Brenner. Indeed, the 300–350 progeny produced by a single animal is even greater than the burst of progeny produced by a T4 phage upon lysis of its E. coli host. The natural C. elegans mode of inbreeding by the self-fertilizing hermaphrodite combined with the ability to cross hermaphrodites with males (Fig. 1) offered conveniences previously enjoyed only in plant genetic systems such as Zea mays, in which crossing or selfing can be manipulated at will. Other key features were the nematode’s small genome (only 20 times that of E. coli ) and anatomical simplicity ( An important reason C. elegans was...