Altered sexual development in roach (Rutilus rutilus) exposed to environmental concentrations of the pharmaceutical 17alpha-ethinylestradiol and associated expression dynamics of aromatases and estrogen receptors.
Wild roach (Rutilus rutilus) inhabiting UK rivers contaminated with estrogenic effluents from wastewater treatment works show altered sexual development, including intersex, and this can impact negatively on their reproductive capabilities. The molecular events underlying these disruptions in gender assignment, however, are still poorly understood. In this study, two isoforms of aromatase (cyp19a1a and cyp19a1b) were cloned from the roach, and effects of exposure to 17alpha-ethinylestradiol (EE(2)) during early life were determined on the expression of both aromatases and on the estrogen receptors (ERs) (subtypes esr1 and esr2b) and analyzed against effects on the progression of gonadal sex differentiation. Exposure to environmentally relevant concentrations of EE(2) during the critical period of sex differentiation resulted in gonadal feminization and all roach exposed to 4 ng EE(2)/l were females. These effects on gonadal development were associated with alterations in the expression of both esr and cyp19a1 genes in bodies and heads of exposed fish with the most marked effects on the expression of esr1 and cyp19a1b. Our findings show that both aromatase isoforms and both ER subtypes are associated with sexual differentiation in roach, and alterations in their expression can signal for disruptions in sexual development.
Lange
Anke
A
School of Biosciences, University of Exeter, Exeter, Devon EX4 4PS, UK. a.lange@exeter.ac.uk
Katsu
Yoshinao
Y
Ichikawa
Rie
R
Paull
Gregory C
GC
Chidgey
Laura L
LL
Coe
Tobias S
TS
Iguchi
Taisen
T
Tyler
Charles R
CR
D000818:Animals; D001141:Aromatase / Q000235:genetics / Q000378:metabolism*; D003530:Cyprinidae / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D052244:Endocrine Disruptors / Q000633:toxicity*; D047628:Estrogen Receptor alpha / Q000235:genetics / Q000378:metabolism*; D047629:Estrogen Receptor beta / Q000235:genetics / Q000378:metabolism*; D004997:Ethinyl Estradiol / Q000633:toxicity*; D005260:Female; D005262:Feminization / Q000139:chemically induced; D029941:Fish Proteins / Q000235:genetics / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006066:Gonads / Q000187:drug effects / Q000196:embryology / Q000378:metabolism; D007527:Isoenzymes; D008297:Male; D046468:Sexual Development / Q000187:drug effects*; D013997:Time Factors; D014818:Vitellogenesis / Q000187:drug effects; D014819:Vitellogenins / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000633:toxicity*
D052244:Endocrine Disruptors; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D029941:Fish Proteins; D007527:Isoenzymes; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D004997:Ethinyl Estradiol; D001141:Aromatase