Publication Date:
2000-11-25
Description:
To study whether cloning resets the epigenetic differences between the two X chromosomes of a somatic female nucleus, we monitored X inactivation in cloned mouse embryos. Both X chromosomes were active during cleavage of cloned embryos, followed by random X inactivation in the embryo proper. In the trophectoderm (TE), X inactivation was nonrandom with the inactivated X of the somatic donor being chosen for inactivation. When female embryonic stem cells with two active X chromosomes were used as donors, random X inactivation was seen in the TE and embryo. These results demonstrate that epigenetic marks can be removed and reestablished on either X chromosome during cloning. Our results also suggest that the epigenetic marks imposed on the X chromosomes during gametogenesis, responsible for normal imprinted X inactivation in the TE, are functionally equivalent to the marks imposed on the chromosomes during somatic X inactivation.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Eggan, K -- Akutsu, H -- Hochedlinger, K -- Rideout, W 3rd -- Yanagimachi, R -- Jaenisch, R -- 5-R35-CA44339/CA/NCI NIH HHS/ -- R01-CA84198/CA/NCI NIH HHS/ -- New York, N.Y. -- Science. 2000 Nov 24;290(5496):1578-81.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/11090356" target="_blank"〉PubMed〈/a〉
Keywords:
Alleles
;
Animals
;
Cell Differentiation
;
*Cloning, Organism
;
*Dosage Compensation, Genetic
;
Embryo, Mammalian/cytology/*metabolism
;
Embryonic and Fetal Development
;
Female
;
Gene Silencing
;
Genes, Reporter
;
Genomic Imprinting
;
Green Fluorescent Proteins
;
Luminescent Proteins/genetics
;
Male
;
Mice
;
Muridae
;
Nuclear Transfer Techniques
;
Oocytes
;
Placenta/metabolism
;
Reverse Transcriptase Polymerase Chain Reaction
;
Stem Cell Transplantation
;
Stem Cells/metabolism
;
Transgenes
;
X Chromosome/*genetics/metabolism
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
