α-Actinin4 nuclear translocation mediates gonadotropin-releasing hormone stimulation of follicle-stimulating hormone β-subunit gene transcription in LβT2 cells

Gonadotropin-releasing hormone (GnRH) regulates the synthesis and secretion of follicle-stimulating hormone (FSH) by stimulating the transcription of Fsh beta gene. Our iTRAQ quantitative proteomics result showed that the abundance of alpha-actinin4 (ACTN4) increased in the nuclei of L beta T2 cells upon GnRH induction. Using RNA interference, reverse transcription and real-time PCR, luciferase and transient transfection assays, we proved that ACTN4 is involved in the regulation of mouse Fsh beta gene (mFsh beta) transcription and its C-terminal calmodulin (CaM)-like domain is crucial for this process. Our study suggests that ACTN4 nuclear translocation mediates GnRH stimulation of mFsh beta gene transcription. (c) 2012 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.