Widespread organ tolerance to Xist loss and X reactivation except under chronic stress in the gut.

Journal Article (Journal Article)

Long thought to be dispensable after establishing X chromosome inactivation (XCI), Xist RNA is now known to also maintain the inactive X (Xi). To what extent somatic X reactivation causes physiological abnormalities is an active area of inquiry. Here, we use multiple mouse models to investigate in vivo consequences. First, when Xist is deleted systemically in post-XCI embryonic cells using the Meox2-Cre driver, female pups exhibit no morbidity or mortality despite partial X reactivation. Second, when Xist is conditionally deleted in epithelial cells using Keratin14-Cre or in B cells using CD19-Cre, female mice have a normal life span without obvious illness. Third, when Xist is deleted in gut using Villin-Cre, female mice remain healthy despite significant X-autosome dosage imbalance. Finally, when the gut is acutely stressed by azoxymethane/dextran sulfate (AOM/DSS) exposure, both Xist-deleted and wild-type mice develop gastrointestinal tumors. Intriguingly, however, under prolonged stress, mutant mice develop larger tumors and have a higher tumor burden. The effect is female specific. Altogether, these observations reveal a surprising systemic tolerance to Xist loss but importantly reveal that Xist and XCI are protective to females during chronic stress.

Full Text

Duke Authors

Cited Authors

  • Yang, L; Yildirim, E; Kirby, JE; Press, W; Lee, JT

Published Date

  • February 25, 2020

Published In

Volume / Issue

  • 117 / 8

Start / End Page

  • 4262 - 4272

PubMed ID

  • 32041873

Pubmed Central ID

  • PMC7049159

Electronic International Standard Serial Number (EISSN)

  • 1091-6490

Digital Object Identifier (DOI)

  • 10.1073/pnas.1917203117


  • eng

Conference Location

  • United States