We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
X chromosome choice occurs independently of asynchronous replication timing.
- Authors
Gribnau, Joost; Luikenhuis, Sandra; Hochedlinger, Konrad; Monkhorst, Kim; Jaenisch, Rudolf
- Abstract
In mammals, dosage compensation is achieved by X chromosome inactivation in female cells. Xist is required and sufficient for X inactivation, and Xist gene deletions result in completely skewed X inactivation. In this work, we analyzed skewing of X inactivation in mice with an Xist deletion encompassing sequence 5 KB upstream of the promoter through exon 3. We found that this mutation results in primary nonrandom X inactivation in which the wild-type X chromosome is always chosen for inactivation, To understand the molecular mechanisms that affect choice, we analyzed the role of replication timing in X inactivation choice. We found that the two Xist alleles and all regions tested on the X chromosome replicate asynchronously before the start of X inactivation. However, analysis of replication timing in cell lines with skewed X inactivation showed no preference for one of the two Xist alleles to replicate early in S-phase before the onset of X inactivation, indicating that asynchronous replication timing does not play a role in skewing of X inactivation.
- Subjects
X chromosome; GENETIC mutation; CELL nuclei; MOLECULAR genetics; CELL culture; SEX-linkage (Genetics)
- Publication
Journal of Cell Biology, 2005, Vol 168, Issue 3, p365
- ISSN
0021-9525
- Publication type
Article
- DOI
10.1083/jcb.200405117