We found a match
Your institution may have rights to this item. Sign in to continue.
- Title
Aberrant patterns of X chromosome inactivation in bovine clones.
- Authors
Xue, Fei; Tian, X Cindy; Du, Fuliang; Kubota, Chikara; Taneja, Maneesh; Dinnyes, Andras; Dai, Yunping; Levine, Howard; Pereira, Lygia V.; Yang, Xiangzhong
- Abstract
In mammals, epigenetic marks on the X chromosomes are involved in dosage compensation. Specifically, they are required for X chromosome inactivation (XCI), the random transcriptional silencing of one of the two X chromosomes in female cells during late blastocyst development. During natural reproduction, both X chromosomes are active in the female zygote. In somatic-cell cloning, however, the cloned embryos receive one active (Xa) and one inactive (Xi) X chromosome from the donor cells. Patterns of XCI have been reported normal in cloned mice, but have yet to be investigated in other species. We examined allele-specific expression of the X-linked monoamine oxidase type A (MAOA) gene and the expression of nine additional X-linked genes in nine cloned XX calves. We found aberrant expression patterns in nine of ten X-linked genes and hypomethylation of Xist in organs of deceased clones. Analysis of MAOA expression in bovine placentae from natural reproduction revealed imprinted XCI with preferential inactivation of the paternal X chromosome. In contrast, we found random XCI in placentae of the deceased clones but completely skewed XCI in that of live clones. Thus, incomplete nuclear reprogramming may generate abnormal epigenetic marks on the X chromosomes of cloned cattle, affecting both random and imprinted XCI.
- Subjects
X chromosome; MONOAMINE oxidase
- Publication
Nature Genetics, 2002, Vol 31, Issue 2, p216
- ISSN
1061-4036
- Publication type
Article
- DOI
10.1038/ng900