1. Academic Validation
  2. RNF12 is an X-Encoded dose-dependent activator of X chromosome inactivation

RNF12 is an X-Encoded dose-dependent activator of X chromosome inactivation

  • Cell. 2009 Nov 25;139(5):999-1011. doi: 10.1016/j.cell.2009.10.034.
Iris Jonkers 1 Tahsin Stefan Barakat Eskeatnaf Mulugeta Achame Kim Monkhorst Annegien Kenter Eveline Rentmeester Frank Grosveld J Anton Grootegoed Joost Gribnau
Affiliations

Affiliation

  • 1 Department of Reproduction and Development, Erasmus MC, University Medical Center, 3000 CA Rotterdam, The Netherlands.
Abstract

In somatic cells of female placental mammals, one X chromosome is inactivated to minimize sex-related dosage differences of X-encoded genes. Random X chromosome inactivation (XCI) in the embryo is a stochastic process, in which each X has an independent probability to initiate XCI, triggered by the nuclear concentration of one or more X-encoded XCI-activators. Here, we identify the E3 ubiquitin ligase RNF12 as an important XCI-activator. Additional copies of mouse Rnf12 or human RNF12 result in initiation of XCI in male mouse ES cells and on both X chromosomes in a substantial percentage of female mouse ES cells. This activity is dependent on an intact open reading frame of Rnf12 and correlates with the transgenic expression level of RNF12. Initiation of XCI is markedly reduced in differentiating female heterozygous Rnf12(+/-) ES cells. These findings provide evidence for a dose-dependent role of RNF12 in the XCI counting and initiation process.

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