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Nuclear Transfer into Mouse Oocytes
Published on: November 29, 2006
Nuclear transplantation: lessons from frogs and mice
Konrad Hochedlinger1, Rudolf Jaenisch
1Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA. hochedlinger@wi.mit.edu
Current Opinion in Cell Biology
|December 11, 2002
Summary
Cloning experiments suggest that nuclei from adult stem cells, not just terminally differentiated cells, may create cloned animals. Cloned animals often exhibit developmental abnormalities regardless of the donor cell type.
Area of Science:
- Developmental Biology
- Genetics
- Reproductive Biology
Background:
- Nuclear transplantation, developed 50 years ago, assesses genetic equivalence of differentiated cell nuclei.
- Cloning experiments in frogs and mice suggest nuclei lose potency during development.
- Adult lymphocytes are totipotent, but origin of clones from terminally differentiated cells remains unproven.
Purpose of the Study:
- To investigate the cellular origin of cloned animals and the potential role of adult stem cells in nuclear transplantation.
- To explore whether less differentiated adult cells, like stem cells, are more efficiently reprogrammed than terminally differentiated cells.
- To analyze common abnormalities observed in cloned animals.
Main Methods:
- Review of existing nuclear transplantation experiments in frogs and mice.
- Analysis of genetic totipotency in adult mature lymphocytes.
- Phenotypic characterization and gene expression analysis of cloned animals.
Main Results:
- Evidence suggests cloned animals may originate from less differentiated adult cells, such as adult stem cells, rather than terminally differentiated cells.
- Adult stem cells might offer higher efficiency and easier reprogramming for cloning.
- Cloned animals consistently display abnormalities, including fetal and placental overgrowth, irrespective of the donor cell type.
Conclusions:
- The cellular origin of cloned animals requires further investigation, with adult stem cells being a plausible source.
- Cloning processes, regardless of donor cell origin, frequently result in developmental abnormalities.
- Subtle genetic and phenotypic abnormalities are common in cloned animals.
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