title: Large-scale transcriptional analysis of bovine embryo biopsies in relation to pregnancy success after transfer to recipients.
abstract: The purpose of this work is to address the relationship between transcriptional profile of embryos and the pregnancy success based on gene expression analysis of blastocyst biopsies taken prior to transfer to recipients. Biopsies (30-40% of the intact embryo) were taken from in vitro-produced day 7 blastocysts (n = 118), and 60-70% were transferred to recipients after reexpansion. Based on the success of pregnancy, biopsies were pooled in three groups (each 10 biopsies) namely: those resulting in no pregnancy (G1), resorbed embryos (G2), and those resulting in calf delivery (G3). Gene expression analysis of these groups was performed using home-made bovine preimplantation-specific cDNA array (219 clones) and BlueChip (with approximately 2,000 clones). Microarray data analysis results revealed a total of 52 and 58 genes were differentially regulated during comparison between G1 vs. G3 and G2 vs. G3. Biopsies resulted in calf delivery were enriched with genes necessary for implantation (COX2 and CDX2), carbohydrate metabolism (ALOX15), growth factor (BMP15), signal transduction (PLAU), and placenta-specific 8 (PLAC8). Biopsies from embryos resulting in resorption are enriched with transcripts involved protein phosphorylation (KRT8), plasma membrane (OCLN), and glucose metabolism (PGK1 and AKR1B1). Biopsies from embryos resulting in no pregnancy are enriched with transcripts involved inflammatory cytokines (TNF), protein amino acid binding (EEF1A1), transcription factors (MSX1, PTTG1), glucose metabolism (PGK1, AKR1B1), and CD9, which is an inhibitor of implantation. In conclusion, we generated direct candidates of blastocyst-specific genes which may play an important role in determining the fate of the embryo after transfer.
authors.affiliation: Institute of Animal Science, Animal Breeding and Husbandry Group, University of Bonn, Bonn, Germany.
authors.forename: Ashraf
authors.initials: A
authors.lastname: El-Sayed
authors.forename: Michael
authors.initials: M
authors.lastname: Hoelker
authors.forename: Franca
authors.initials: F
authors.lastname: Rings
authors.forename: Dessie
authors.initials: D
authors.lastname: Salilew
authors.forename: Danyel
authors.initials: D
authors.lastname: Jennen
authors.forename: Ernst
authors.initials: E
authors.lastname: Tholen
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Sirard
authors.forename: Karl
authors.initials: K
authors.lastname: Schellander
authors.forename: Dawit
authors.initials: D
authors.lastname: Tesfaye
mesh_terms: D000818:Animals; D001706:Biopsy; D001755:Blastocyst / Q000378:metabolism; D002417:Cattle / Q000196:embryology* / Q000235:genetics / Q000378:metabolism; D004624:Embryo Transfer; D004622:Embryo, Mammalian / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005260:Female; D020869:Gene Expression Profiling; D007150:Immunohistochemistry; D051957:MSX1 Transcription Factor / Q000235:genetics / Q000378:metabolism; D008954:Models, Biological; D020411:Oligonucleotide Array Sequence Analysis; D011247:Pregnancy; D011256:Pregnancy Outcome; D011257:Pregnancy Proteins / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D051957:MSX1 Transcription Factor; D011257:Pregnancy Proteins