The co-chaperone XAP2 is required for activation of hypothalamic thyrotropin-releasing hormone transcription in vivo. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue EMBO Reports Année : 2006

The co-chaperone XAP2 is required for activation of hypothalamic thyrotropin-releasing hormone transcription in vivo.

Résumé

Transcriptional control of hypothalamic thyrotropin-releasing hormone (TRH) integrates central regulation of the hypothalamo-hypophyseal-thyroid axis and hence thyroid hormone (triiodothyronine (T(3))) homeostasis. The two beta thyroid hormone receptors, TRbeta1 and TRbeta2, contribute to T(3) feedback on TRH, with TRbeta1 having a more important role in the activation of TRH transcription. How TRbeta1 fulfils its role in activating TRH gene transcription is unknown. By using a yeast two-hybrid screening of a mouse hypothalamic complementary DNA library, we identified a novel partner for TRbeta1, hepatitis virus B X-associated protein 2 (XAP2), a protein first identified as a co-chaperone protein. TR-XAP2 interactions were TR isoform specific, being observed only with TRbeta1, and were enhanced by T(3) both in yeast and mammalian cells. Furthermore, small inhibitory RNA-mediated knockdown of XAP2 in vitro affected the stability of TRbeta1. In vivo, siXAP2 abrogated specifically TRbeta1-mediated (but not TRbeta2) activation of hypothalamic TRH transcription. This study provides the first in vivo demonstration of a regulatory, physiological role for XAP2.
Fichier non déposé

Dates et versions

hal-00093424 , version 1 (13-09-2006)

Identifiants

  • HAL Id : hal-00093424 , version 1

Citer

* Froidevaux Ms, * Berg P, * Seugnet I, * Decherf S, * Becker N, et al.. The co-chaperone XAP2 is required for activation of hypothalamic thyrotropin-releasing hormone transcription in vivo.. EMBO Reports, 2006, X, pp.X. ⟨hal-00093424⟩

Collections

MNHN CNRS
25 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More