RESUMEN
While the role of transcription factors and coactivators in controlling enhancer activity and chromatin structure linked to gene expression is well established, the involvement of corepressors is not. Using inflammatory macrophage activation as a model, we investigate here a corepressor complex containing GPS2 and SMRT both genome-wide and at the Ccl2 locus, encoding the chemokine CCL2 (MCP-1). We report that corepressors co-occupy candidate enhancers along with the coactivators CBP (H3K27 acetylase) and MED1 (mediator) but act antagonistically by repressing eRNA transcription-coupled H3K27 acetylation. Genome editing, transcriptional interference, and cistrome analysis reveals that apparently related enhancer and silencer elements control Ccl2 transcription in opposite ways. 4C-seq indicates that corepressor depletion or inflammatory signaling functions mechanistically similarly to trigger enhancer activation. In ob/ob mice, adipose tissue macrophage-selective depletion of the Ccl2 enhancer-transcribed eRNA reduces metaflammation. Thus, the identified corepressor-eRNA-chemokine pathway operates in vivo and suggests therapeutic opportunities by targeting eRNAs in immuno-metabolic diseases.
Asunto(s)
Quimiocina CCL2/genética , Proteínas Co-Represoras/genética , Elementos de Facilitación Genéticos , Péptidos y Proteínas de Señalización Intracelular/genética , Co-Represor 2 de Receptor Nuclear/genética , Obesidad/genética , Elementos Silenciadores Transcripcionales , Tejido Adiposo/inmunología , Tejido Adiposo/patología , Animales , Sistemas CRISPR-Cas , Quimiocina CCL2/inmunología , Proteínas Co-Represoras/inmunología , Edición Génica , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Histona Acetiltransferasas/genética , Histona Acetiltransferasas/inmunología , Histonas/genética , Histonas/inmunología , Humanos , Péptidos y Proteínas de Señalización Intracelular/inmunología , Lipopolisacáridos/farmacología , Activación de Macrófagos/efectos de los fármacos , Masculino , Subunidad 1 del Complejo Mediador/genética , Subunidad 1 del Complejo Mediador/inmunología , Ratones , Ratones Obesos , Co-Represor 2 de Receptor Nuclear/inmunología , Obesidad/inmunología , Obesidad/patología , Células RAW 264.7 , ARN no Traducido/genética , ARN no Traducido/inmunología , Transducción de SeñalRESUMEN
Human in vitro generated monocyte-derived dendritic cells (moDCs) and macrophages are used clinically, e.g., to induce immunity against cancer. However, their physiological counterparts, ontogeny, transcriptional regulation, and heterogeneity remains largely unknown, hampering their clinical use. High-dimensional techniques were used to elucidate transcriptional, phenotypic, and functional differences between human in vivo and in vitro generated mononuclear phagocytes to facilitate their full potential in the clinic. We demonstrate that monocytes differentiated by macrophage colony-stimulating factor (M-CSF) or granulocyte macrophage colony-stimulating factor (GM-CSF) resembled in vivo inflammatory macrophages, while moDCs resembled in vivo inflammatory DCs. Moreover, differentiated monocytes presented with profound transcriptomic, phenotypic, and functional differences. Monocytes integrated GM-CSF and IL-4 stimulation combinatorically and temporally, resulting in a mode- and time-dependent differentiation relying on NCOR2. Finally, moDCs are phenotypically heterogeneous and therefore necessitate the use of high-dimensional phenotyping to open new possibilities for better clinical tailoring of these cellular therapies.
Asunto(s)
Células Dendríticas/inmunología , Interleucina-4/inmunología , Macrófagos/inmunología , Monocitos/inmunología , Co-Represor 2 de Receptor Nuclear/inmunología , Transducción de Señal/inmunología , Diferenciación Celular , Linaje de la Célula , Células Dendríticas/citología , Células Dendríticas/efectos de los fármacos , Perfilación de la Expresión Génica , Regulación de la Expresión Génica , Factor Estimulante de Colonias de Granulocitos y Macrófagos/farmacología , Humanos , Inmunofenotipificación , Interleucina-4/genética , Interleucina-4/farmacología , Activación de Macrófagos , Factor Estimulante de Colonias de Macrófagos/farmacología , Macrófagos/citología , Macrófagos/efectos de los fármacos , Monocitos/citología , Monocitos/efectos de los fármacos , Co-Represor 2 de Receptor Nuclear/genética , Cultivo Primario de Células , Factores de Tiempo , Transcripción GenéticaRESUMEN
Distinct CD4(+) T cell subsets are critical for host defense and immunoregulation. Although these subsets can act as terminally differentiated lineages, they have been increasingly noted to demonstrated plasticity. MicroRNAs are factors that control T cell stability and plasticity. Here we report that naturally occurring regulatory T cells (T(reg) cells) had high expression of the microRNA miR-10a and that miR-10a was induced by retinoic acid and transforming growth factor-ß (TGF-ß) in inducible T(reg) cells. By simultaneously targeting the transcriptional repressor Bcl-6 and the corepressor Ncor2, miR-10a attenuated the phenotypic conversion of inducible T(reg) cells into follicular helper T cells. We also found that miR-10a limited differentiation into the T(H)17 subset of helper T cells and therefore represents a factor that can fine-tune the plasticity and fate of helper T cells.
