| First Author | Gribnau J | Year | 2005 |
| Journal | J Cell Biol | Volume | 168 |
| Issue | 3 | Pages | 365-73 |
| PubMed ID | 15668296 | Mgi Jnum | J:95871 |
| Mgi Id | MGI:3527909 | Doi | 10.1083/jcb.200405117 |
| Citation | Gribnau J, et al. (2005) X chromosome choice occurs independently of asynchronous replication timing. J Cell Biol 168(3):365-73 |
| abstractText | 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. |
