Structure, Chromosomal Localization, and Expression Analysis of the Mouse Inhibin/Activin βC(Inhbc) Gene

The mouse inhibin/activin βCgene (Inhbc), a member of the transforming growth factor-β (TGF-β) superfamily, was cloned, mapped, and characterized. The gene spans approximately 14 kb, is composed of two exons, and maps to the distal region of mouse chromosome 10, which is syntenic to chromosome 12q13.1, where the human inhibin/activin βCgene (INHBC) maps. The primary translation product is a preproprotein of 352 amino acids. The mature C-terminal domain of 116 amino acids shares 94% identity with its human homolog. Primer extension analysis shows that transcription starts approximately 130 bp upstream of the translation initiation site, and no TATA box was found in the promoter. Ribonuclease protection analyses reveal that mouseInhbcis predominantly expressed in adult liver. Embryonic expression is detected beginning from Day 14.5 of gestation.