Novel method for demonstrating nuclear contribution in mouse nuclear transfer

Area of Science:

• Reproductive Biology
• Developmental Biology
• Genetics

Background:

• Confirming nuclear contribution is critical for nuclear transfer experiments.
• Demonstrating nuclear contribution in early embryos is challenging.
• lacZ transgenic mice offer a potential solution for visualizing nuclear origin.

Purpose of the Study:

• To establish a reliable method for confirming nuclear contribution in nuclear transfer embryos and offspring.
• To utilize lacZ expression as a distinct marker for nuclear origin.
• To validate the totipotency of nuclear transfer blastocysts.

Main Methods:

• Generated nuclear transfer embryos using metaphase-arrested nuclei from lacZ transgenic (Zin40) and non-transgenic 4-cell embryos.
• Utilized X-gal staining to detect lacZ expression, indicated by blue nuclei.
• Confirmed blastocyst totipotency through the generation of live-born offspring.

Main Results:

• Transgenic nuclear transfer embryos, fetuses, and pups exhibited distinctive blue nuclei after X-gal staining.
• The blue nuclei pattern directly correlated with the transgenic origin of donor nuclei.
• Successfully confirmed nuclear contribution in both embryos and live offspring.

Conclusions:

• lacZ transgenic mice provide an effective and straightforward marker for confirming nuclear contribution in nuclear transfer.
• This method simplifies the assessment of nuclear origin in nuclear transfer embryos and progeny.
• The marker facilitates further investigation into the developmental potential of nuclear transfer embryos, including chimaeric embryo analysis.