Cloning of bovine estrogen receptor beta (ERbeta): expression of novel deleted isoforms in reproductive tissues.
cDNAs coding for bovine estrogen receptor beta (ERbeta) isoforms were cloned from bovine granulosa cells using a combination of several RT-PCR strategies. The cloned full-length receptor contains an open reading frame of 474 amino acids encoding a protein with high homology to the ERbeta sequences from other species. A second isoform nearly totally lacking the ligand binding domain was cloned that is expressed to relatively high levels in reproductive tissues. Expression of both ERbeta isoforms is down-regulated in corpus luteum and endometrium during the luteal phase of the female cycle. In addition, in granulosa cells several ERbeta isoforms carrying major internal deletions were detected by RT-PCR and cloned. Transient transfection studies expressing the two major bovine ERbeta isoforms together with an ERE reporter construct show estrogen-dependent transactivation by the full-length isoform, whereas the isoform lacking the ligand binding domain did not show any transactivation.
Walther
N
N
Institute for Hormone and Fertility Research, University of Hamburg, Germany. walther@ihf.de
Lioutas
C
C
Tillmann
G
G
Ivell
R
R
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D047629:Estrogen Receptor beta; D005260:Female; D006107:Granulosa Cells / Q000502:physiology*; D008969:Molecular Sequence Data; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D011960:Receptors, Estrogen / Q000096:biosynthesis / Q000235:genetics*
D018076:DNA, Complementary; D047629:Estrogen Receptor beta; D020033:Protein Isoforms; D011960:Receptors, Estrogen