Heterochromatin dynamics during epithelial-to-mesenchymal transition

Although heterochromatin is enriched with repressive traits, it is actively transcribed, giving rise to large amounts of non-coding RNAs. These transcripts are responsible for the formation and maintenance of heterochromatin, but little is known about how their transcription is regulated. In this th...

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Detalhes bibliográficos
Autor: Millanes Romero, Alba
Formato: tesis doctoral
Estado:Versión publicada
Fecha de publicación:2014
País:España
Recursos:CBUC, CESCA
Repositorio:TDR. Tesis Doctorales en Red
OAI Identifier:oai:www.tdx.cat:10803/129339
Acesso em linha:http://hdl.handle.net/10803/129339
Access Level:acceso abierto
Palavra-chave:Snail1
LOXL2
EMT
Major satellite
Heterochromatin
Pericentromeric repeats
Chromocenter
Major satèl·lits
Heterocromatina
Repeticions pericentromèriques
Cromocentre
576
Descrição
Resumo:Although heterochromatin is enriched with repressive traits, it is actively transcribed, giving rise to large amounts of non-coding RNAs. These transcripts are responsible for the formation and maintenance of heterochromatin, but little is known about how their transcription is regulated. In this thesis we show that Snail1 transcription factor represses mouse pericentromeric transcription and regulates heterochromatin organization through the action of the H3K4 deaminase LOXL2. Snail1 has a key role in epithelial-to-mesenchymal transition (EMT). We show that, also during this process, Snail1 is responsible for pericentromeric transcription regulation. At the onset of EMT, one of the major structural heterochromatin proteins, HP1α, is transiently released from heterochromatin foci in a Snail1/LOXL2 dependent manner, concomitantly with a down-regulation of major satellite transcription. Moreover, prevention of major satellite transcripts down-regulation compromises the migratory and invasive behaviour of EMT resulting mesenchymal cells. We propose that Snail1 and LOXL2 regulate heterochromatin during this process, which may be crucial to allow the genome reorganization required to complete EMT.