Physiol. Genomics 33: 65-77, 2008.
First published December 18, 2007; doi:10.1152/physiolgenomics.00223.2007
1094-8341/08 $8.00
Received 25 September 2007;
accepted in final form 11 December 2007.
Physiological Genomics 33:65-77 (2008)
1094-8341/08 $8.00 © 2008 American Physiological Society
Aberrant gene expression patterns in placentomes are associated with phenotypically normal and abnormal cattle cloned by somatic cell nuclear transfer
Robin E. Everts1,
Pascale Chavatte-Palmer2,
Anthony Razzak1,
Isabelle Hue2,
Cheryl A. Green1,
Rosane Oliveira1,
Xavier Vignon2,
Sandra L. Rodriguez-Zas1,
X. Cindy Tian3,
Xiangzhong Yang3,
Jean-Paul Renard2 and
Harris A. Lewin1
1 Department of Animal Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois
2 UMR Biologie du Développement et Reproduction, Institut National de la Recherche Agronomique, Jouy-en-Josas, France
3 Center for Regenerative Biology/Department of Animal Sciences, University of Connecticut, Storrs, Connecticut
Transcription profiling of placentomes derived from somatic cell nuclear transfer (SCNT, n = 20), in vitro fertilization (IVF, n = 9), and artificial insemination (AI, n = 9) at or near term development was performed to better understand why SCNT and IVF often result in placental defects, hydrops, and large offspring syndrome (LOS). Multivariate analysis of variance was used to distinguish the effects of SCNT, IVF, and AI on gene expression, taking into account the effects of parturition (term or preterm), sex of fetus, breed of dam, breed of fetus, and pathological finding in the offspring (hydrops, normal, or other abnormalities). Differential expression of 20 physiologically important genes was confirmed with quantitative PCR. The largest effect on placentome gene expression was attributable to whether placentas were collected at term or preterm (i.e., whether the collection was because of disease or to obtain stage-matched controls) followed by placentome source (AI, IVF, or SCNT). Gene expression in SCNT placentomes was dramatically different from AI (n = 336 genes; 276 >2-fold) and from IVF (n = 733 genes; 162 >2-fold) placentomes. Functional analysis of differentially expressed genes (DEG) showed that IVF has significant effects on genes associated with cellular metabolism. In contrast, DEG associated with SCNT are involved in multiple pathways, including cell cycle, cell death, and gene expression. Many DEG were shared between the gene lists for IVF and SCNT comparisons, suggesting that common pathways are affected by the embryo culture methods used for IVF and SCNT. However, the many unique gene functions and pathways affected by SCNT suggest that cloned fetuses may be starved and accumulating toxic wastes due to placental insufficiency caused by reprogramming errors. Many of these genes are candidates for hydrops and LOS.
placenta; bovine; reprogramming
Copyright © 2008 by the American Physiological Society.