Super-resolution imaging uncovers key temporal changes in chromatin structure and pluripotent gene reactivation in single reprogramming cells

Elucidating the mechanism of somatic cell reprogramming has been hampered by the limitations of iPSC systems to uncover the correctly reprogramming cells. Here, by using the highly efficient heterokaryon system we dissected the temporal dynamics of key molecular events during the early stages of plu...

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Detalhes bibliográficos
Autor: Martinez Sarmiento, Jose Angel
Formato: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2023
País:España
Recursos:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/688218
Acesso em linha:http://hdl.handle.net/10803/688218
Access Level:acceso abierto
Palavra-chave:Heterokaryon
Reprogramming
Pluripotency
Chromatin
Microscopy
Heterocarionte
Reprogramación
Pluripotencia
Cromatina
Microscopía
576
Descrição
Resumo:Elucidating the mechanism of somatic cell reprogramming has been hampered by the limitations of iPSC systems to uncover the correctly reprogramming cells. Here, by using the highly efficient heterokaryon system we dissected the temporal dynamics of key molecular events during the early stages of pluripotency conversion at the single-cell level using super resolution imaging approaches. We revealed that, immediately after fusion, the somatic nucleus undergoes a dramatic removal of repressive histone modification marks, such as H3K9me3 and H3K273me3; followed by a late stage of global chromatin de-compaction as evidenced by a decreased nucelosomal density. Importantly, the transcriptional reactivation of the key pluripotency genes NANOG and OCT4 follows distinct mechanisms and kinetics, where a local, open chromatin environment preceded the late reactivation of NANOG, while OCT4 transcriptional reactivation occurs earlier and at higher levels without evident changes in its local nano-scale chromatin configuration.