Bridge-1 is expressed in human granulosa cells and is involved in the activin A signaling cascade

The present study investigates the expression of the coactivator Bridge-1 in the human ovary and its role in activin A signaling in the human granulosa cell line HGL-5. Expression of Bridge-1 can be stimulated by activin A, an important factor for follicle maturation, matching the increase of Smad 2, 3, and 4; treatment with Bridge-1–small interfering RNA is decreasing not only the expression of Bridge-1 but also the expression of Smad2, 3, and 4 in HGL-5 cells.