| First Author | Susperreguy S | Year | 2011 |
| Journal | Exp Cell Res | Volume | 317 |
| Issue | 6 | Pages | 706-23 |
| PubMed ID | 21122806 | Mgi Jnum | J:170741 |
| Mgi Id | MGI:4947203 | Doi | 10.1016/j.yexcr.2010.11.008 |
| Citation | Susperreguy S, et al. (2011) Visualization by BiFC of different C/EBPbeta dimers and their interaction with HP1alpha reveals a differential subnuclear distribution of complexes in living cells. Exp Cell Res 317(6):706-23 |
| abstractText | How the co-ordinated events of gene activation and silencing during cellular differentiation are influenced by spatial organization of the cell nucleus is still poorly understood. Little is known about the molecular mechanisms controlling subnuclear distribution of transcription factors, and their interplay with nuclear proteins that shape chromatin structure. Here we show that C/EBPbeta not only associates with pericentromeric heterochromatin but also interacts with the nucleoskeleton upon induction of adipocyte differentiation of 3T3-L1 cells. Different C/EBPbeta dimers localize in different nuclear domains. Using BiFC in living cells, we show that LAP (Liver Activating Protein) homodimers localize in euchromatin and heterochromatin. In contrast, LIP (Liver Inhibitory Protein) homodimers localize exclusively in heterochromatin. Importantly, their differential subnuclear distribution mirrors the site for interaction with HP1alpha. HP1alpha inhibits LAP transcriptional capacity and occupies the promoter of the C/EBPbeta-dependent gene c/ebpalpha in 3T3-L1 preadipocytes. When adipogenesis is induced, HP1alpha binding decreases from c/ebpalpha promoter, allowing transcription. Thus, the equilibrium among different pools of C/EBPbeta associated with chromatin or nucleoskeleton, and dynamic changes in their interaction with HP1alpha, play key roles in the regulation of C/EBP target genes during adipogenesis. |
