Effect of ICSI on gene expression and development of mouse preimplantation embryos.
BACKGROUND
In vitro culture (IVC) and IVF of preimplantation mouse embryos are associated with changes in gene expression. It is however not known whether ICSI has additional effects on the transcriptome of mouse blastocysts.


METHODS
We compared gene expression and development of mouse blastocysts produced by ICSI and cultured in Whitten's medium (ICSI(WM)) or KSOM medium with amino acids (ICSI(KSOMaa)) with control blastocysts flushed out of the uterus on post coital Day 3.5 (in vivo). In addition, we compared gene expression in embryos generated by IVF or ICSI using WM. Global pattern of gene expression was assessed using the Affymetrix 430 2.0 chip.


RESULTS
Blastocysts from ICSI fertilization have a reduction in the number of trophoblastic and inner cell mass cells compared with embryos generated in vivo. Approximately 1000 genes are differentially expressed between ICSI blastocyst and in vivo blastocysts; proliferation, apoptosis and morphogenetic pathways are the most common pathways altered after IVC. Unexpectedly, expression of only 41 genes was significantly different between embryo cultured in suboptimal conditions (WM) or optimal conditions (KSOM(aa)).


CONCLUSIONS
Our results suggest that fertilization by ICSI may play a more important role in shaping the transcriptome of the developing mouse embryo than the culture media used.
Giritharan
G
G
Department of Obstetric, Gynecology and Reproductive Sciences, University of California, San Francisco, San Francisco, CA 94143, USA.
Li
M W
MW
Di Sebastiano
F
F
De Sebastiano
F
F
Esteban
F J
FJ
Horcajadas
J A
JA
Lloyd
K C K
KC
Donjacour
A
A
Maltepe
E
E
Rinaudo
P F
PF
D000818:Animals; D001755:Blastocyst / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000096:biosynthesis; D046149:Embryo Culture Techniques; D047108:Embryonic Development; D005260:Female; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D000073864:Histone Deacetylase 6; D006655:Histone Deacetylases / Q000096:biosynthesis; D011495:Histone-Lysine N-Methyltransferase; D051379:Mice; D051788:Myeloid-Lymphoid Leukemia Protein / Q000096:biosynthesis; D040081:Protein Array Analysis; D020554:Sperm Injections, Intracytoplasmic; D014157:Transcription Factors / Q000096:biosynthesis
D004268:DNA-Binding Proteins; C499335:Smarca1 protein, mouse; D014157:Transcription Factors; D051788:Myeloid-Lymphoid Leukemia Protein; D011495:Histone-Lysine N-Methyltransferase; C510860:Kmt2d protein, mouse; C499033:Hdac6 protein, mouse; D000073864:Histone Deacetylase 6; D006655:Histone Deacetylases