Interaction of estrogen receptor alpha transactivation domain with MTA1 decreases in old mouse brain.

We have reported earlier that estrogen receptor (ER) alpha-transactivation domain (TAD) interacted with four nuclear proteins of 100 kD, 80 kD, 68 kD, and 50 kD of mouse brain and identified 68 kD as p68 RNA helicase and 50 kD as beta-tubulin. In this paper, we describe the identification of 80 kD nuclear protein as metastasis associated protein 1 (MTA1) and its interaction and expression in the brain of aging mice. Far-Western blotting and immunoprecipitation data revealed lower interaction of MTA1 in old than adult mice of both sexes. Furthermore, adult male showed lower expression of protein as compared to adult female. Altogether these findings suggest that age-dependent decrease in the expression of MTA1 and its interaction with ERalpha-TAD may influence the estrogen-mediated signaling pathway during aging of mouse brain.