The giant panda (Ailurapoda melanoleuca) somatic nucleus can dedifferentiate in rabbit ooplasm and support early development of the reconstructed egg

The giant panda skeletal muscle cells, uterus epithelial cells and mammary gland cells from an adult individual were cultured and used as nucleus dono r for the construction of interspecies embryos by transferring them into en ucleated rabbit eggs. All the three kinds of somatic cells were able to rep rogram in rabbit ooplasm and support early embryo development, of which mam mary gland cells were proven to be the Lest, followed by uterus epithelial cells and skeletal muscle cells. The experiments showed that direct injecti on of mammary gland cell into enucleated rabbit ooplasm, combined with in v ivo development in ligated rabbit oviduct, achieved higher blastocyst devel opment than in vitro culture after the somatic cell was injected into the p erivitelline space and fused with the enucleated egg by electrical stimulat ion. The chromosome analysis demonstrated that the genetic materials in rec onstructed blastocyst cells were the same as that in panda somatic cells. I n addition, giant panda mitochondrial DNA (mtDNA) was shown to exist in the interspecies reconstructed blastocyst. The data suggest that (i) the abili ty of ooplasm to dedifferentiate somatic cells is not species-specific; (ii ) there is compatibility between interspecies somatic nucleus and ooplasm d uring early development of the reconstructed egg.