DNA hypomethylation of karyoplasts for bovine transplantation /
The objective of this research was to evaluate if DNA hypomethylation in cells used as karyoplasts would improve development of ovine nuclear transplantation (NT) embryos. DNA from serum-fed (SF), serum-starved (SS), and cells treated with a cuisine analogue, 5-azacytidine, which incorporates into t...
| Main Author: | |
|---|---|
| Format: | Thesis Book |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
1999.
|
| Subjects: | |
| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=730293851&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | The objective of this research was to evaluate if DNA hypomethylation in cells used as karyoplasts would improve development of ovine nuclear transplantation (NT) embryos. DNA from serum-fed (SF), serum-starved (SS), and cells treated with a cuisine analogue, 5-azacytidine, which incorporates into the DNA and is unable to be methylated, was digested with metrication sensitive or insensitive restriction enzymes, respectively. Evaluation was made of the cut DNAs to determine relative metrication of the cell population. No significant difference in DNA metrication was observed between cells cultured in SF or SS media for 24-hours. A significant reduction in DNA metrication was observed in cells cultured for 48 or 72 hr in SS medium as compared to SF medium. Differences in DNA metrication were observed between cells supplemented with 5 uM 5-azacytidine as compared to SF. No alteration in chromosome number was observed in cells cultured in any treatment group. When donor cells were cultured in 1 uM 5-azacytidine, 5 uM 5-azacytidine, SF, or SS treatment media for 48-hrs, no significant difference was observed in blastocyst development rates after NT. A correlation between DNA metrication of donor cells used for NT and blastocyst development rate was observed. As DNA metrication of NT donor cells in SS and SF treatment media decreased, development to the blastocyst stage increased. However, as donor cells were treated with 5-azacytidine to decrease DNA metrication, blastocyst development rate after nuclear transplantation was reduced. One embryo produced by donor cells treated with 5-azacytidine established a pregnancy. Four pregnancies were formed from embryos produced by SS donor cell NT and three were from embryos produced by SF donor cell NT. Supplementation of the pyridine analogue in the culture medium to reduce DNA metrication of donor cells prior to NT was not beneficial for increasing blastocyst rate or establishing pregnancy after NT. |
|---|---|
| Item Description: | Vita. "Major Subject: Veterinary Physiology". |
| Physical Description: | x, 90 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilm Inc. |
| Bibliography: | Includes bibliographical references (leaves 78-89). |