The characterization of macroH2A beyond vertebrates supports an ancestral origin and conserved role for histone variants in chromatin.
Epigenetics
; 11(6): 415-25, 2016 06 02.
Article
em En
| MEDLINE
| ID: mdl-27082816
ABSTRACT
Histone variants play a critical role in chromatin structure and epigenetic regulation. These "deviant" proteins have been historically considered as the evolutionary descendants of ancestral canonical histones, helping specialize the nucleosome structure during eukaryotic evolution. Such view is now challenged by 2 major observations first, canonical histones present extremely unique features not shared with any other genes; second, histone variants are widespread across many eukaryotic groups. The present work further supports the ancestral nature of histone variants by providing the first in vivo characterization of a functional macroH2A histone (a variant long defined as a specific refinement of vertebrate chromatin) in a non-vertebrate organism (the mussel Mytilus) revealing its recruitment into heterochromatic fractions of actively proliferating tissues. Combined with in silico analyses of genomic data, these results provide evidence for the widespread presence of macroH2A in metazoan animals, as well as in the holozoan Capsaspora, supporting an evolutionary origin for this histone variant lineage before the radiation of Filozoans (including Filasterea, Choanoflagellata and Metazoa). Overall, the results presented in this work help configure a new evolutionary scenario in which histone variants, rather than modern "deviants" of canonical histones, would constitute ancient components of eukaryotic chromatin.
Palavras-chave
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Cromatina
/
Histonas
/
Evolução Molecular
Limite:
Animals
Idioma:
En
Revista:
Epigenetics
Assunto da revista:
GENETICA
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Estados Unidos