Imprinted X chromosome inactivation at the gamete-to-embryo transition.
Mol Cell
; 84(8): 1442-1459.e7, 2024 Apr 18.
Article
em En
| MEDLINE
| ID: mdl-38458200
ABSTRACT
In mammals, dosage compensation involves two parallel processes (1) X inactivation, which equalizes X chromosome dosage between males and females, and (2) X hyperactivation, which upregulates the active X for X-autosome balance. The field currently favors models whereby dosage compensation initiates "de novo" during mouse development. Here, we develop "So-Smart-seq" to revisit the question and interrogate a comprehensive transcriptome including noncoding genes and repeats in mice. Intriguingly, de novo silencing pertains only to a subset of Xp genes. Evolutionarily older genes and repetitive elements demonstrate constitutive Xp silencing, adopt distinct signatures, and do not require Xist to initiate silencing. We trace Xp silencing backward in developmental time to meiotic sex chromosome inactivation in the male germ line and observe that Xm hyperactivation is timed to Xp silencing on a gene-by-gene basis. Thus, during the gamete-to-embryo transition, older Xp genes are transmitted in a "pre-inactivated" state. These findings have implications for the evolution of imprinting.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Inativação do Cromossomo X
/
RNA Longo não Codificante
Limite:
Animals
Idioma:
En
Revista:
Mol Cell
Assunto da revista:
BIOLOGIA MOLECULAR
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Estados Unidos