Title Relationship between Environmental Temperature and Sex Differentiation in Fish
Authers Michiaki YAMASHITA and Nanami KAWAGUCHI
Keywords sex differentiation, temperature, environmental stress, apoptosis, zebrafish, spermatogenesis
Citation Bull. Fish. Res. Agen. supplement No. 4, 13-17, 2006
Heat stress and other environmental factors influence the determination of phenotypic sex in fish in addition to genetic sex determination. In this review, we focused on sex differentiation and sex reversal under high temperature and other stress conditions in fish. Heat-induced germ cell deficiency was found in males and females of the South American atherinid fish Odontesthes bonariensis and Patagonia hatcheri. Zebrafish are also sensitive to environmental factors that may influence sex determination, and oocyte apoptosis has been characterized in spermatogenesis during sex differentiation. Since heat shock and other environmental stresses induce apoptosis in various cell types, such stress conditions may induce oocyte apoptosis in the gonads during sex differentiation, followed by spermatogenesis and testicular formation, leading to sexreversed phenotypic males. Therefore, temperature elevation by global climate change in the ocean may affect sex differentiation and sex reversal in various fish species during early life stages.
URI http://www.fra.affrc.go.jp/bulletin/bull/bull-b4/03.pdf