Polycomb regulates mesoderm cell fate-specification in embryonic stem cells through activation and repression mechanisms

Polycomb complexes (PRC1 and PRC2) are essential regulators of epigenetic gene silencing in embryonic and adult stem cells. Emerging evidence suggests that the core subunit composition regulates distinct biological processes, yet little is known about the mechanistic underpinnings of how differently...

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Detalles Bibliográficos
Autores: Morey Ramonell, Lluís, Santanach Buxaderas, Alexandra, 1988-, Blanco, Enrique, Aloia, Luigi, Nora, Elphège P., Bruneau, Benoit G., Di Croce, Luciano
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Universitat Pompeu Fabra
Repositorio:Repositorio Digital de la UPF
OAI Identifier:oai:repositori.upf.edu:10230/27101
Acceso en línea:http://hdl.handle.net/10230/27101
http://dx.doi.org/10.1016/j.stem.2015.08.009
Access Level:acceso abierto
Palabra clave:Diferenciació cel·lular
Regulació genètica
Descripción
Sumario:Polycomb complexes (PRC1 and PRC2) are essential regulators of epigenetic gene silencing in embryonic and adult stem cells. Emerging evidence suggests that the core subunit composition regulates distinct biological processes, yet little is known about the mechanistic underpinnings of how differently composed Polycomb complexes instruct and maintain cell fate. Here we find that Mel18, also known as Pcgf2 and one of six Pcgf paralogs, uniquely regulates PRC1 to specify mesoderm cell fate in embryonic stem cells. Mechanistically, Mel18 functions as a classical Polycomb protein during early cardiac mesoderm differentiation by repressing pluripotency, lineage specification, late cardiac differentiation, and negative regulators of the BMP pathway. However, Mel18 also positively regulates expression of key mesoderm transcription factors, revealing an unexpected function of Mel18 in gene activation during cardiac differentiation. Taken together, our findings reveal that Mel18 is required to specify PRC1 function in both a context- and stage-specific manner.