Two estrogen receptors expressed in the teleost fish, Sparus aurata: cDNA cloning, characterization and tissue distribution. | - CCMAR -

Journal Article

TitleTwo estrogen receptors expressed in the teleost fish, Sparus aurata: cDNA cloning, characterization and tissue distribution.
Publication TypeJournal Article
AuthorsSocorro, S, Power, DM, Olsson, PE, Canario, AVM
Year of Publication2000
JournalJ Endocrinol
Date Published2000 Aug
KeywordsAmino Acid Sequence, Animals, Base Sequence, Blotting, Northern, Bone and Bones, DNA, Complementary, Estrogen Receptor alpha, Estrogen Receptor beta, Female, Hermaphroditic Organisms, Intestines, Kidney, Liver, Male, Molecular Sequence Data, Myocardium, Ovary, Receptors, Estrogen, Reverse Transcriptase Polymerase Chain Reaction, Sea Bream, Sequence Alignment, Sequence Analysis, DNA, Sex Determination Processes, Testis

Estrogen is an essential hormone for many reproductive and non-reproductive functions. The function of estrogen in the reproductive cycle of seabream (Sparus aurata), a protandrous hermaphrodite teleost fish, is complex but it is understood to be involved in sex inversion, a process that occurs in some individuals during the second reproductive season. Estrogen action is mediated by two estrogen receptor (ER) subtypes designated alpha and beta. As a step to understanding the mechanisms of estrogen action during natural and induced sex reversal in seabream, we have isolated two cDNAs encoding distinct forms of ER homologous to mammalian ERalpha and ERbeta. The seabream ERalpha clone (sbERalpha1), which was truncated in the A/B domain, corresponded to a variant differing in five amino acids from another recently cloned sbERalpha. The ERbeta clone (sbERbeta) encoded a protein 559 amino acids long and showed only 40% identity to sbERalpha. Northern blot analysis of liver and ovary mRNA indicated the presence of several transcripts of the two receptor subtypes. PCR analysis showed that the two receptors differed in their expression pattern. sbERalpha had a more restricted distribution, occurring mainly in testis, liver and heart, and sbERbeta was present in most tissues, being more abundant in ovary, testis, liver, intestine and kidney. The presence in seabream of two ERs with several ER transcripts and their pattern of distribution are consistent with the widespread effects of estrogen in different tissues.


Alternate JournalJ. Endocrinol.
PubMed ID10927619
CCMAR Authors