Cloning and characterization of estrogen receptor α in mummichog, Fundulus heteroclitus

MOLECULAR AND CELLULAR ENDOCRINOLOGY

卷:203

Article

Urushitani, H ; Nakai, M ; Inanaga, H ; Shimohigashi, Y ; Shimizu, A ; Katsu, Y ; Iguchi, T

关键词: estrogen receptor alpha;    cloning;    receptor binding assay;    vitellogenin;    Fandulus heteroclitus;   

DOI  :  10.1016/S0303-7207(03)00118-7

来源: Elsevier

【 摘 要 】

Developmental exposure to 17beta-estradiol (E-2) induced the death of embryos and fry, malformations, sex reversal, and incomplete ossification of vertebrae and cranial bones in the cyprinodont fish, the mummichog (Fundulus heteroclitus). To clarify the mechanism by which exogenous estrogens caused these developmental effects, we determined the sequence of an estrogen receptor (ER) coding region, encoded by 620 amino acid residues. This region shared 80% identity to that of ERalpha of medaka (Oryzias latipes). Northern blot analysis showed that two ERalpha mRNAs with 5.5 and 4 kb were expressed in the liver. These mRNAs were strongly induced by E2 stimulation. The 4 kb mRNA was expressed 8 h after treatment, whereas the 5.5 kb mRNA was not induced until 12 h after E2 stimulation. Vitellogenin (VTG) was expressed 8 It after E2 stimulation in the male liver. Receptor binding assays using the protein of F heteroclitus ERalpha (fhERalpha) ligand binding domain showed that alkylphenols bind to fhERalpha with a higher affinity (50 times or more) as compared with the human ERalpha. The present results demonstrate that the fhERalpha has a sequence very similar to that of medaka, and the mRNA for this receptor was induced by E-2-stimulation, followed subsequently by VTG expression. Furthermore, alkylphenols bind to fhERalpha more efficiently than to human ERalpha. (C) 2003 Elsevier Science Ireland Ltd. All rights reserved.

【 授权许可】

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