title: Expression of DNA repair genes in porcine oocytes before and after fertilization by ICSI using freeze-dried sperm.
abstract: Boar sperm freeze-dried with trehalose showed a protective effect against sperm DNA fragmentation. However, normal fertilization and embryonic development were not improved. Damaged sperm may activate maternal DNA repair genes when injected into oocytes. Therefore, we investigated the expression profile of some DNA repair genes in porcine oocytes after intra-cytoplasmic sperm injection. First, the expression levels of MGMT, UDG, XPC, MSH2, XRCC6 and RAD51 genes that are concerned with different types of DNA repair were examined in in vitro mature (IVM) oocytes injected with ejaculated sperm, or freeze-dried sperm with or without trehalose. Quantitative reverse transcription polymerase chain reaction revealed that expression of six DNA repair genes in the oocytes at 4 h after injection did not differ among the four groups. Next, we investigated the gene expression levels of these genes at different stages of maturation. The relative expression levels of UDG and XPC were significantly up-regulated in mature oocytes compared with earlier stages. Furthermore, there was an increased tendency in relative expression of MSH2 and RAD51. These results suggested two possible mechanisms that messenger RNA of DNA repair genes are either accumulated during IVM to be ready for fertilization or increased expression levels of DNA repair genes in oocytes caused by suboptimal IVM conditions.
authors.affiliation: Division of Animal Sciences, National Institute of Agrobiological Sciences, Tsukuba, Japan. kiku@affrc.go.jp.|Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan. kiku@affrc.go.jp.|Laboratory of Embryo Technology, Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam. kiku@affrc.go.jp.
authors.forename: Nguyen Thi
authors.initials: NT
authors.lastname: Men
authors.affiliation: Division of Animal Sciences, National Institute of Agrobiological Sciences, Tsukuba, Japan.|The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kikuchi
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Tsukuba, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Furusawa
authors.affiliation: Division of Animal Sciences, National Institute of Agrobiological Sciences, Tsukuba, Japan.
authors.forename: Thanh Quang
authors.initials: TQ
authors.lastname: Dang-Nguyen
authors.affiliation: Genetically Modified Organism Research Center, National Institute of Agrobiological Sciences, Tsukuba, Japan.
authors.forename: Michiko
authors.initials: M
authors.lastname: Nakai
authors.affiliation: Agrogenomics Research Center, National Institute of Agrobiological Sciences, Tsukuba, Japan.
authors.forename: Atsunori
authors.initials: A
authors.lastname: Fukuda
authors.affiliation: Division of Animal Sciences, National Institute of Agrobiological Sciences, Tsukuba, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Noguchi
authors.affiliation: Division of Animal Sciences, National Institute of Agrobiological Sciences, Tsukuba, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kaneko
authors.affiliation: Laboratory of Embryo Technology, Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam.
authors.forename: Nguyen
authors.initials: N
authors.lastname: Viet Linh
authors.affiliation: Laboratory of Embryo Technology, Institute of Biotechnology, Vietnam Academy of Science and Technology, Hanoi, Vietnam.
authors.forename: Bui
authors.initials: B
authors.lastname: Xuan Nguyen
authors.affiliation: Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan.
authors.forename: Atsushi
authors.initials: A
authors.lastname: Tajima
mesh_terms: D000818:Animals; D053938:DNA Fragmentation; D004260:DNA Repair / Q000235:genetics*; D005260:Female; D005306:Fertilization / Q000235:genetics* / Q000502:physiology; D005612:Freeze Drying / Q000379:methods*; D015870:Gene Expression; D008297:Male; D009865:Oocytes; D012333:RNA, Messenger; D012662:Semen Preservation / Q000379:methods*; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*; D013552:Swine / Q000235:genetics* / Q000502:physiology; D013997:Time Factors; D014199:Trehalose
chemical_list: D012333:RNA, Messenger; D014199:Trehalose
keywords: DNA repair genes; ICSI; freeze-dried sperm; gene expression; pig