QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online December 7, 2008

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in Development Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content Social Bookmarking                         What's this?

A-repeat view of X-inactivation

During early development, the inactivation of one X chromosome in female mammals ensures equivalent X-linked gene expression in male (XY) and female (XX) embryos. X-inactivation is triggered by the association of non-coding Xist (X-inactive specific transcript) RNA with one X chromosome. In ES cells, the conserved A-repeat of the Xist RNA is then required to silence that chromosome. Now, on p. 139, Hoki and colleagues report that the A-repeat is also required for X-inactivation during mouse embryogenesis. Surprisingly, however, a lack of Xist RNA, rather than defective silencing by the mutated RNA, causes the failure of imprinted X-inactivation (the inactivation of the paternal X in the extraembryonic tissues) in embryos carrying a paternally transmitted A-repeat-deleted Xist allele. Furthermore, the normally silent paternal copy of Tsix (a negative regulator of Xist) is ectopically activated in these A-repeat-deleted embryos. The researchers suggest, therefore, that the genomic region encoding the A-repeat is required for the appropriate transcriptional regulation of the Xist/Tsix loci and subsequent X-inactivation in mouse embryos.

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

Related articles in Development:

A proximal conserved repeat in the Xist gene is essential as a genomic element for X-inactivation in mouse

Yuko Hoki, Naomi Kimura, Minako Kanbayashi, Yuko Amakawa, Tatsuya Ohhata, Hiroyuki Sasaki, and Takashi Sado
Development 2009 136: 139-146. [Abstract] [Full Text]  

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in Development Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content Social Bookmarking                         What's this?