The transcription factor FBI-1 inhibits SAM68-mediated BCL-X alternative splicing and apoptosis
Article first published online: 10 FEB 2014
© 2014 The Authors
Volume 15, Issue 4, pages 419–427, April 2014
How to Cite
Bielli, P., Busà, R., Di Stasi, S. M., Munoz, M. J., Botti, F., Kornblihtt, A. R. and Sette, C. (2014), The transcription factor FBI-1 inhibits SAM68-mediated BCL-X alternative splicing and apoptosis. EMBO reports, 15: 419–427. doi: 10.1002/embr.201338241
- Issue published online: 2 APR 2014
- Article first published online: 10 FEB 2014
- Manuscript Revised: 12 DEC 2013
- Manuscript Accepted: 12 DEC 2013
- Manuscript Received: 9 DEC 2013
- Association for International Cancer Research (AICR)
- Associazione Italiana Ricerca sul Cancro (AIRC)
- Ministry of Health Ricerca Corrente to the Fondazione Santa Lucia
- alternative splicing;
Alternative splicing (AS) is tightly coupled to transcription for the majority of human genes. However, how these two processes are linked is not well understood. Here, we unveil a direct role for the transcription factor FBI-1 in the regulation of AS. FBI-1 interacts with the splicing factor SAM68 and reduces its binding to BCL-X mRNA. This, in turn, results in the selection of the proximal 5′ splice site in BCL-X exon 2, thereby favoring the anti-apoptotic BCL-XL variant and counteracting SAM68-mediated apoptosis. Conversely, depletion of FBI-1, or expression of a SAM68 mutant lacking the FBI-1 binding region, restores the ability of SAM68 to induce BCL-XS splicing and apoptosis. FBI-1's role in splicing requires the activity of histone deacetylases, whose pharmacological inhibition recapitulates the effects of FBI-1 knockdown. Our study reveals an unexpected function for FBI-1 in splicing modulation with a direct impact on cell survival.
The oncogenic transcription factor FBI-1 regulates alternative splicing by preventing the splicing regulator SAM68 from binding to BCL-X mRNA. This increases anti-apoptotic BCL-X isoform expression and cell survival.
- The transcription factor FBI-1 directly interacts with the splicing regulator SAM68.
- FBI-1 impairs binding of SAM68 to BCL-X mRNA and thus promotes production of the anti-apoptotic BCL-X isoform and cell survival.
- FBI-1's effect on BCL-X splicing requires histone deacetylase activity.