Transcriptional Profiling of Pig Embryogenesis by Using a 15-K Member Unigene Set Specific for Pig Reproductive Tissues and Embryos1

Abstract

Differential mRNA expression patterns were evaluated between germinal vesicle oocytes (pgvo), four-cell (p4civv), blastocyst (pblivv), and in vitro-produced four-cell (p4civp) and in vitro-produced blastocyst (pblivp) stage embryos to determine key transcripts responsible for early embryonic development in the pig. Five comparisons were made: pgvo to p4civv, p4civv to pblivv, pgvo to pblivv, p4civv to p4civp, and pblivv to pblivp. ANOVA (P < 0.05) was performed with the Benjamini and Hochberg false-discovery-rate multiple correction test on each comparison. A comparison of pgvo to p4civv, p4civv to pblivv, and pgvo to pblivv resulted in 3214, 1989, and 4528 differentially detected cDNAs, respectively. Real-time PCR analysis on seven transcripts showed an identical pattern of changes in expression as observed on the microarrays, while one transcript deviated at a single cell stage. There were 1409 and 1696 differentially detected cDNAs between the in vitro- and in vivo-produced embryos at the four-cell and blastocyst stages, respectively, without the Benjamini and Hochberg false-discovery-rate multiple correction test. Real-time polymerase chain reaction (PCR) analysis on four genes at the four-cell stage showed an identical pattern of gene expression as found on the microarrays. Real-time PCR analysis on four of five genes at the blastocyst stage showed an identical pattern of gene expression as found on the microarrays. Thus, only 1 of the 39 comparisons of the pattern of gene expression exhibited a major deviation between the microarray and the real-time PCR. These results illustrate the complex mechanisms involved in pig early embryonic development.

Effect of in vitro fertilization on gene expression and development of mouse preimplantation embryos

“…Whitworth et al (2005) analyzed the differences between IVF and in vivo embryos in the porcine model by using a tissue-specific 19 968 spot cDNA microarray. Interestingly, cluster analysis revealed that IVF and control embryos were different at the four-cell stage, but they did not separate in independent branches at the blastocyst stage, indicating a less dramatic effect of culture on embryos at this latter stage.…”

The quiet embryo hypothesis: Molecular characteristics favoring viability

“…A transcriptomics study of mouse and pig embryos showed that the mRNA for ubiquitin ligase, an essential ubiquitin-conjugating enzyme, was present at higher levels in in vivo-derived 2-and 4-cell stage embryos (Whitworth et al, 2005;Zeng and Schultz, 2005), respectively, as compared with IVP embryos. This suggests that endogenous amino acid recycling may occur at a lower level in vitro.…”

Revealing the bovine embryo transcript profiles during early in vivo embryonic development

“…However, the unavailability of adequate sequence data for numerous species has kept the microarray technology beyond the reach of investigators working on economically and scientifically important large domestic species such as cattle, pigs, and sheep. Possible solutions to this problem is either the use of cross-species hybridizations (Robert et al 2000, Dalbies-Tran & Mermillod 2003, Adjaye et al 2004, Vallee et al 2008 or the fabrication of homemade cDNA arrays (Yao et al 2004, Whitworth et al 2005, Vallee et al 2006, Dessie et al 2007, Ghanem et al 2007. The commercial arrays (Affymetrix) that have been made available for the cow greatly facilitate bovine gene expression profiling (Fair et al 2007).…”