In vivo Polycomb kinetics and mitotic chromatin binding distinguish stem cells from differentiated cells.
Genes Dev
; 26(8): 857-71, 2012 Apr 15.
Article
en En
| MEDLINE
| ID: mdl-22508729
ABSTRACT
Epigenetic memory mediated by Polycomb group (PcG) proteins must be maintained during cell division, but must also be flexible to allow cell fate transitions. Here we quantify dynamic chromatin-binding properties of PHGFP and PCGFP in living Drosophila in two cell types that undergo defined differentiation and mitosis events. Quantitative fluorescence recovery after photobleaching (FRAP) analysis demonstrates that PcG binding has a higher plasticity in stem cells than in more determined cells and identifies a fraction of PcG proteins that binds mitotic chromatin with up to 300-fold longer residence times than in interphase. Mathematical modeling examines which parameters best distinguish stem cells from differentiated cells. We identify phosphorylation of histone H3 at Ser 28 as a potential mechanism governing the extent and rate of mitotic PC dissociation in different lineages. We propose that regulation of the kinetic properties of PcG-chromatin binding is an essential factor in the choice between stability and flexibility in the establishment of cell identities.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Proteínas Represoras
/
Células Madre
/
Cromatina
/
Diferenciación Celular
/
Mitosis
Tipo de estudio:
Prognostic_studies
Límite:
Animals
Idioma:
En
Año:
2012
Tipo del documento:
Article