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Updated: Aug 10, 2026
09:48
Production of Transgenic Xenopus laevis by Restriction Enzyme Mediated Integration and Nuclear Transplantation
Published on: August 21, 2010
Transgenic cattle produced by reverse-transcribed gene transfer in oocytes
A W Chan1, E J Homan, L U Ballou
1Endocrinology-Reproductive Physiology Program, University of Wisconsin, 1675 Observatory Drive, Madison, WI 53706, USA.
Summary
Gene transfer into oocytes is possible without nuclear envelope breakdown, enabling transgenic livestock production. This method bypasses mitosis, utilizing the natural meiotic arrest of oocytes for efficient gene integration and offspring development.
Area of Science:
- Reproductive biology
- Molecular biology
- Genetics
Background:
- Retroviral integration typically requires nuclear envelope breakdown during mitosis.
- Oocytes in metaphase II (MII) arrest lack a nuclear envelope for extended periods.
- This unique state presents an opportunity for gene transfer strategies.
Purpose of the Study:
- To investigate the feasibility of gene transfer into MII-arrested oocytes using retroviral vectors.
- To assess the potential for producing transgenic offspring from oocytes undergoing gene transfer.
- To explore the implications for transgenic livestock production and natural transgenesis.
Main Methods:
- Injection of pseudotyped, replication-defective retroviral vectors into the perivitelline space of bovine oocytes.
- Maintaining oocytes in MII arrest.
- Monitoring for successful gene transfer and development of offspring.
Main Results:
- Successful reverse-transcribed gene transfer occurred in MII-arrested oocytes.
- A majority of the resulting offspring were transgenic.
- This demonstrates that nuclear envelope breakdown is not universally required for retroviral integration.
Conclusions:
- Gene transfer into oocytes is achievable during MII arrest, bypassing the need for nuclear envelope breakdown.
- This method offers a viable strategy for producing transgenic livestock.
- The findings provide insights into recursive transgenesis and potential applications in assisted reproduction.
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