Molecular cloning and expression of Turkey inhibin-α and -βa subunits

We isolated cDNA encoding turkey inhibin-α (tINH-α) and -βA (tINH-βA) subunits from the turkey ovary using reverse transcription-polymerase chain reaction (RT-PCR). The isolated α subunit and βA subunit included the entire open reading frames encoding 329 and 424 amino acids, respectively. The amino acid sequences of mature tINH-α subunit and tINH-βA subunit (12.6 and 12.9 kDa proteins, respectively), established via DNA sequence analysis, were highly conserved between the chicken and various mammals. Northern blot analysis revealed that the transcripts of tINH-α and tINH-βA subunits were approximately 1.7 and 8.4 kb, respectively. In various stages of follicular development, tINH-α mRNA was highly expressed in small white follicles as compared to postovulatory and regressed follicles, whereas tINH-βA mRNA was predominately expressed in preovulatory F5 follicles.