Developmental Competence and Pluripotency Gene Expression of Cattle Cloned Embryos Derived from Donor Cells Treated with 5-aza-2'-deoxycytidine
نویسندگان
چکیده
BACKGROUND Reconstructed embryos from terminally differentiated somatic cells have revealed high levels of genomic methylation which results in inappropriate expression patterns of imprinted and non-imprinted genes. These aberrant expressions are probably responsible for different abnormalities during the development of clones. Improvement in cloning competency may be achieved through modification of epigenetic markers in donor cells. MATERIALS AND METHODS Our objective was to determine if treatment of donor cells for 72 hours with 5-aza-2'-deoxycytidine (5-aza-dc; 0-0.3 μM), a DNA methyl transferase inhibitor, improved development and expression of Oct-4. RESULTS In comparison with untreated cells, 0.01 and 0.08 μM 5-aza-dc treated cells insignificantly decreased the blastocyst rate (32.1% vs. 28.6% and 27.2%, respectively) while it was significant for 0.3 μM treated cells (6.5%). Embryo quality as measured by the total cell number (TCN) decreased in a dose-related fashion, which was significant at 0.08 and 0.3 μM 5-aza-dc treated cells when compared with 0 and 0.01 μM 5-aza-dc treated cells. Although reconstructed embryos from 0.08 and 0.3 μM 5-aza-dc treated cells showed lower levels of DNA methylation and histone H3 acetylation, development to blastocyst stage was decreased. The epigenetic markers of embryos cloned from 0.01 μM 5-aza-dc remained unchanged. CONCLUSION These results show that 5-aza-dc is not a suitable choice for modifying nuclear reprogramming. Finally, it was concluded that the wide genomic hypomethylation induced by 5-aza-dc deleteriously impacts the developmental competency of cloned embryos.
منابع مشابه
Developmental Competence and Pluripotency Gene Expression of Cattle Cloned Embryos Derived from Donor Cells Treated with 5-aza-2'-deoxycytidine
متن کامل
Treating Cloned Embryos, But Not Donor Cells, with 5-aza-2’-deoxycytidine Enhances the Developmental Competence of Porcine Cloned Embryos
The efficiency of cloning by somatic cell nuclear transfer (SCNT) has remained low. In most cloned embryos, epigenetic reprogramming is incomplete, and usually the genome is hypermethylated. The DNA methylation inhibitor 5-aza-2'-deoxycytidine (5-aza-dC) could improve the developmental competence of cow, pig, cat and human SCNT embryos in previous studies. However, the parameters of 5-aza-dC tr...
متن کاملO-7: Improved In Vitro Development of Cloned Bovine Embryos Using S-Adenosylhomocysteine,A Non-Toxic Epigenetic
Background: Development of cloned bovine embryos. Materials and Methods: Oocytes collection,oocyte denudation, oocyte enucleation, nuclear transfer, electrofusion, reconstructed embryo activation, culture of reconstructed and IVF embryo,and treatment with SAH post fusion interval Treatment of reconstructed embryos with TSA for 12 hours after activation, preparation of somatic donor cells, donor...
متن کاملO-18: Epigenetic Modification of Cloned Embryo Development; State of ART
Background: At the outset of the somatic cell nuclear transfer (SCNT) process, the chromatin structure of the somatic cell which governs its state of differentiation undergoes dramatic changes, called reprogramming, and is compelled back to the embryonic stage. However, the overall epigenetic makeup of the resultant cloned embryos has been acknowledged far different from the fertilized embryos....
متن کاملO-12: Study of Expression of DevelopmentalGenes in SCNT Cloned Embryos
(SCNT) embryos of buffaloes. 2. To study gene expression profile of important developmental genes at different stages of SCNT cloned embryo. 3. To study epigenetic reprogramming during early developments of SCNT embryos Materials and Methods: Expression analysis of developmental genes was done in different (ovarian granulose and cumulus and skin fibroblasts) donor cells; in vitro maturing oocyt...
متن کامل