The non-coding RNA Xist plays a key role in the process of X chromosome inactivation (XCI) and is thus essential for dosage compensation of X-linked genes in females. The 5′ region of Xist RNA contains a conserved element termed the A-repeat that is required for the silencing function of Xist in embryonic stem cells, but how this region functions during development is unclear. Now, Takashi Sado and co-workers explore this by introducing into mice a mutated Xist allele that produces Xist RNA lacking the A-repeat region (p. 2784). They first report that imprinted XCI is compromised upon paternal transmission of this allele. The authors further show that the mutant form of Xist is able to coat the X chromosome but fails to silence it in embryonic and extraembryonic tissues. Surprisingly, however, mutant Xist RNA is still able to silence a subset of genes in the trophoblast. Finally, the authors reveal that the failure of imprinted XCI has a more significant impact on genome-wide gene expression than expected; changes in the expression of both X-linked and autosomal genes are observed. Together these findings provide new insights into Xist-mediated gene silencing but also raise the intriguing possibility that dosage compensation regulates X-linked genes as well as gene expression more globally.
X-citing insights into dosage compensation
X-citing insights into dosage compensation. Development 1 August 2017; 144 (15): e1501. doi:
Download citation file:
Advertisement
Cited by
Biologists @ 100 - join us in Liverpool in March 2025

We are excited to invite you to a unique scientific conference, celebrating the 100-year anniversary of The Company of Biologists, and bringing together our different communities. The conference will incorporate the Spring Meetings of the BSCB and the BSDB, the JEB Symposium Sensory Perception in a Changing World and a DMM programme on antimicrobial resistance. Find out more and register by 28 February 2025 to join us in March 2025 in Liverpool, UK.
Call for papers – Lifelong Development: the Maintenance, Regeneration and Plasticity of Tissues

Development invites you to submit your latest research to our upcoming special issue – Lifelong Development: the Maintenance, Regeneration and Plasticity of Tissues. This issue will be coordinated by Guest Editors Meritxell Huch (Max Planck Institute of Molecular Cell Biology and Genetics, Germany) and Mansi Srivastava (Harvard University and Museum of Comparative Zoology, USA), working alongside our team of academic Editors. Submit your articles by 15 May 2025.
A case for broadening our view of mechanism in developmental biology

In this Perspective, B. Duygu Özpolat and colleagues survey researchers on their views on what it takes to infer mechanism in developmental biology. They examine what factors shape our idea of what we mean by ‘mechanism’ and suggest a path forward that embraces a broad outlook on the diversity of studies that advance knowledge in our field.
In preprints
Did you know that Development publishes perspectives on recent preprints? These articles help our readers navigate the ever-growing preprint literature. We welcome proposals for ‘In preprints’ articles, so please do get in touch if you’d like to contribute.