[
1990]
Sex determination in the C. elegans germ line addresses two major problems of biological control. First, any regulation that directs male or female development in all tissues must rely on tissue-specific controls to specify a particular pathway of differentiation (e.g., sperm or oocyte) in a single tissue. The C. elegans germ line provides several technical advantages for analyzing sex determination in a single tissue, including powerful genetic selections (Kimble, 1988) and ease of micro-injection (Kimble et al., 1982). Second, the self-fertility of the C. elegans hermaphrodite depends upon its transient production of sperm in an otherwise female animal. Analysis of sex determination in the hermaphrodite germ line should therefore shed light on the evolution of hermaphrodites from females. Here, we review our efforts towards identifying the regulatory elements that control the C. elegans hermaphrodite germ line to produce sperm and