Haploidy influences Bak and Bcl-xL mRNA expression and increases incidence of apoptosis in porcine embryos.
The objective of this study was to determine developmental pattern, total cell number, apoptosis and apoptosis-related gene expression in haploid and diploid embryos following parthenogenetic activation. In vitro-matured porcine oocytes were activated by electrical pulses and cultured in the absence or presence of cytochalasin B for 3 h. Zygotes with two polar bodies (haploid) and one polar body (diploid) were carefully selected and were further cultured in NCSU 23 medium containing 0.4% bovine serum albumin (BSA) for 7 days. The percentage of development to blastocyst stage was higher (p < 0.01) in the diploid than in the haploid parthenotes. In haploid blastocysts, average total cell number was significantly reduced (p < 0.05) and apoptosis was increased at day 7. The relative abundance of Bcl-xL and Bak mRNA in the diploid blastocysts was similar to that of in vivo-fertilized embryos. However, Bcl-xL was significantly decreased, and Bak mRNA was significantly increased (p < 0.05) in haploid parthenotes compared with the diploid parthenotes. These results suggest that the haploid state affects apoptosis-related gene expression which results in increased apoptosis and decreased developmental competence of haploid parthenotes.
Department of Animal Sciences, Research Center for Bioresource and Health, Cheongju, Chungbuk, South Korea.
Yu-Jeong
YJ
Jeong
Xiang-Shun
XS
Cui
Bong-Ki
BK
Kim
Il Hwa
IH
Kim
Teoan
T
Kim
Yon-Bok
YB
Chung
Nam-Hyung
NH
Kim
D000818:Animals; D017209:Apoptosis / Q000235:genetics*; D001755:Blastocyst / Q000166:cytology / Q000473:pathology* / Q000502:physiology; D002452:Cell Count; D004171:Diploidy; D046149:Embryo Culture Techniques; D004622:Embryo, Mammalian; D005260:Female; D005307:Fertilization in Vitro; D018507:Gene Expression Regulation, Developmental; D006238:Haploidy; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D010312:Parthenogenesis; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013552:Swine / Q000196:embryology / Q000235:genetics; D015053:Zygote / Q000166:cytology; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051020:bcl-X Protein
D008565:Membrane Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D050998:bcl-2 Homologous Antagonist-Killer Protein; D051020:bcl-X Protein