Function of the her‐1 gene is required for maintenance of male differentiation in adult tissues of C. elegans

Function of the sex‐determining gene her‐1 is required in XO embryos cf C. elegans to specify male development. Using a temperature‐sensitive mutant of her‐1, we show that when XO males reared at a permissive temperature are shifted as adults to a nonpermissive temperature, they initiate vitellogenin synthesis in the intestine and oocyte production in the germline. A similar shift has no effect on her‐1(+) males. We conclude that sexual differentiation of the intestine and germline is plastic, requiring her‐1 expression throughout adulthood for maintenance of the male state. © 1994 Wiley‐Liss, Inc.