Bovine endometrium at day 18 of pregnancy after transfer of in vitro produced or somatic cell nuclear transfer embryos

ABSTRACT: Although somatic cell nuclear transfer (SCNT) cloning is more efficient in bovine than in all other species tested so far, there is a high rate of pregnancy failure that has been linked to structural and functional abnormalities of the placenta. We tested the hypothesis that these changes may originate from disturbed embryo-maternal interactions in the pre-implantation period. Therefore, we evaluated the transcriptome response of the endometrium to SCNT embryos (produced from five different donor cell cultures) as compared to embryos derived from in vitro fertilization (IVF). SCNT embryos and IVF embryos were cultured under identical conditions to the blastocyst stage (Day 8) and transferred to recipients. The recipients were slaughtered at day 18 of pregnancy and the uterus was recovered. Pregnancy was verified by the presence of at least one normally developed embryo. Transcriptome profiling of endometrium samples using a custom cDNA microarray covering transcripts expressed in the endometrium and/or oviduct epithelium revealed 58 transcripts that were differently abundant between endometrium samples from SCNT vs. IVF pregnancies. Prominent examples are NR2F2 (encoding the orphan nuclear receptor COUP-TFII) and GJA1 (encoding connexin 43). Both transcripts are known to play important roles in placentation and were significantly less abundant in endometrium from SCNT vs. IVF pregnancies. These findings suggest that placental failure in bovine clone pregnancies may originate from abnormal embryo-maternal communication already in the pre- or peri-implantation period. Endometrium transcriptome profiles may serve as a novel readout to evaluate SCNT embryos for their ability to induce pregnancy with a functional placenta. Keywords: response to different embryos Nineteen German Fleckvieh (Simmental) heifers were slaughtered at day 18 of pregnancy. Cycle-synchronized recipient heifers received either IVP or SCNT embryos at day 7 of the estrous cycle. Animals were slaughtered at day 18. Endometrial (intercaruncular) tissue samples were obtained from 10 pregnant animals after transfer of IVP embryos and from 9 pregnant animals after transfer of SCNT embryos.

ORGANISM(S): Bos taurus

SUBMITTER: Stefan Bauersachs 

PROVIDER: E-GEOD-13663 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress