Molecular cloning of estrogen receptor α and expression pattern of estrogen receptor subtypes in male and female goldfish

• Published in: Molecular and cellular endocrinology Vol. 204; no. 1; pp. 169 - 177
• Main Authors: Choi, C.Y., Habibi, H.R.
• Format: Journal Article
• Language: English
• Published: Ireland Elsevier Ireland Ltd 30-06-2003
• Subjects: Animals; Base Sequence; cDNA cloning; Cloning, Molecular; DNA, Complementary - biosynthesis; DNA, Complementary - isolation & purification; Estrogen Receptor alpha; Estrogen Receptor beta; Estrogen receptor α; Female; Gene Expression Profiling; Goldfish; Male; Molecular Sequence Data; Receptors, Estrogen - analysis; Receptors, Estrogen - genetics; Receptors, Estrogen - metabolism; RNA, Messenger - analysis; RNA, Messenger - metabolism; RT-PCR; Sequence Analysis, DNA; Tissue Distribution; β-1; β-2; Estrogen receptor α; cDNA cloning; RT-PCR; β-2; β-1; Goldfish; Tissue distribution
• ISSN: 0303-7207; 1872-8057
• DOI: 10.1016/S0303-7207(02)00182-X

Estrogen plays an important role in the regulation of gonadotropin production in vertebrates. In this study, we isolated the estrogen receptor (ER) α cDNA from the goldfish pituitary. Primers for ERα were designed based on the similarity of selected regions (C and E domains) of known ER genes. Full-length cDNA sequence for ERα was determined by 3′ and 5′ RACE procedures. ERα cDNA clone was found to contain 2087 nucleotides including an open reading frame that encodes 564 amino acids, with a molecular weight of 62.8 kDa. We also cloned ERβ-1 and ERβ-2 from the published information and investigated the expression pattern of these ER subtypes in a variety of tissues in male and female goldfish by reverse transcriptase-polymerase chain reaction (RT-PCR). Significant variations in the relative expression of ERα, ERβ-1 and ERβ-2 were observed in different tissues in male and female goldfish. Pituitary was found to have the highest expression level of ERα in both male and female goldfish. Significantly, lower levels of ERα expression were observed in the brain, ovary, testis, liver, muscle, heart and intestine. Ovary and testis were found to have higher transcript levels of ERβ-1 with much lower levels in the brain, pituitary, liver, muscle and heart. The ERβ-2 was found to be expressed strongly in the pituitary followed by intestine with lower expression in other tissues. The present study provides molecular characterization of ERα, and information on tissue specific distribution of different ER subtypes in male and female goldfish.