Synergism between temperature and estradiol: A common pathway in turtle sex determination?

摘要: In many reptiles, the temperature at which eggs are incubated determines sex of hatchlings. Administration estradiol will counteract masculinizing effects a male-producing temperature, resulting in female To address whether and estrogen biologically equivalent, two experiments were conducted with red-eared slider turtle, Trachemys scripta. first experiment, varying dosages administered Stage 17 (the middle temperature-sensitive window) to maintained tempera- tures, 26°C (which normally produces all males) 28.2"C mostly males but lies threshold transition from male- female-producing temperatures). Results indicate that exert synergistic effect on determination. second experi- ment, was different stages embryonic development. The results indi- cate an estrogen-sensitive period ranging 14 through 21, similar for this species. these consistent hypothesis act common pathway temperature-dependent A variety abundance reptiles exhibit determination (TSD) incubation em- bryo it hatches as male or (Bull, '80; Raynaud Pieau, '85; Ewert Nelson, '91). Application steroid hor- mone causes embryos rep- tiles develop (Pieau, '74; Gutzke Bull, '86; Bull et al., '88; Crews '89, '91); some estradiol-sensitive species have TSD, genotypic (GSD). As yet, there is virtually no evidence endogenous might be involved natural process Although any demonstration indeed awaits elucidation molecu- lar details pathway, one attempt demonstrate not by revealing estradiol-induced has characteristics than does normal present study explores avenues comparing estra- diol turtle One set investigates