2000/09/26 by Mary Beth Hawkins, Joseph W. Thornton, David Crews +3 · 5 citations
Biochemistry, Genetics and Molecular Biology · #Estrogen and related hormone effects #Reproductive biology and impacts on aquatic species #Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
paper · doi:10.1073/pnas.97.20.10751
openalex publication_date 2000/09/26 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
This paper describes three distinct estrogen receptor (ER) subtypes: ERalpha, ERbeta, and a unique type, ERgamma, cloned from a teleost fish, the Atlantic croaker Micropogonias undulatus; the first identification of a third type of classical ER in vertebrate species. Phylogenetic analysis shows that ERgamma arose through gene duplication from ERbeta early in the teleost lineage and indicates that ERgamma is present in other teleosts, although it has not been recognized as such. The Atlantic croaker ERgamma shows amino acid differences in regions important for ligand binding and receptor activation that are conserved in all other ERgammas. The three ER subtypes are genetically distinct and have different distribution patterns in Atlantic croaker tissues. In addition, ERbeta and ERgamma fusion proteins can each bind estradiol-17beta with high affinity. The presence of three functional ERs in one species expands the role of ER multiplicity in estrogen signaling systems and provides a unique opportunity to investigate the dynamics and mechanisms of ER evolution.