title: Effects of vitrification for germinal vesicle and metaphase II oocytes on subsequent centromere cohesion and chromosome aneuploidy in mice.
abstract: The present study examined the effect of vitrification on oocyte aneuploidy and centromere cohesion. Firstly, germinal vesicle (GV) and in vitro matured oocytes (metaphase II, MII) were vitrified by open-pulled straw method. Secondly, thawed GV oocytes were matured in vitro to detect the aneuploidy rate and the sister inter-kinetochore (iKT) distance (in situ spreading and immunofluorescent staining). The results revealed that the sister iKT distance and the aneuploidy rate in eggs matured from vitrified-thawed GV oocytes were higher than that from in vivo matured, in vitro matured, and in vitro matured frozen oocytes (0.47 ± 0.03 vs. 0.33 ± 0.01 vs. 0.33 ± 0.02 vs. 0.34 ± 0.01 μm; P < 0.01 and 22.9% vs. 6.5% vs. 5.8% vs. 11.8%; P < 0.05, respectively). Furthermore, the percentage of sister chromosome pairs whose sister iKT distances were higher than 0.9 μm in eggs matured from vitrified-thawed GV oocytes (8.7%) was higher than that from in vivo matured (1.6%), in vitro matured (1.6%), and in vitro matured frozen oocytes (2.3%) (P < 0.05). The sister iKT distance was associated with centromere cohesion. To investigate whether vitrification of GV oocytes deteriorated centromere cohesion by affecting cohesin complex formation, thawed and fresh GV oocytes were used to detect the cohesin subunits (SMC1β, STAG3, SMC3, and REC8) mRNA expression (quantitative real-time polymerase chain reaction). The relative expression of three cohesin subunits (SMC1β, STAG3, and SMC3) was significantly decreased in GV oocytes after vitrification. In conclusion, vitrification of GV oocytes may result in the subsequent deterioration of centromere cohesion and an increase in the aneuploidy rate. MII oocytes may be the ideal candidate to avoid aneuploidy for fertility cryopreservation.
authors.affiliation: Laboratory of Animal Embryonic Biotechnology, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China.
authors.forename: Jinmei
authors.initials: J
authors.lastname: Cheng
authors.affiliation: Laboratory of Animal Embryonic Biotechnology, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China.
authors.forename: Baoyu
authors.initials: B
authors.lastname: Jia
authors.affiliation: Laboratory of Animal Embryonic Biotechnology, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China.
authors.forename: Tianyu
authors.initials: T
authors.lastname: Wu
authors.affiliation: Institute of Animal Genetics and Breeding, College of Animal Science and Technology, Sichuan Agricultural University (Chengdu Campus), Wenjiang, P.R. China.
authors.forename: Guangbin
authors.initials: G
authors.lastname: Zhou
authors.affiliation: College of Biological Science, China Agricultural University, Beijing, P.R. China.
authors.forename: Yunpeng
authors.initials: Y
authors.lastname: Hou
authors.affiliation: Laboratory of Animal Embryonic Biotechnology, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China. Electronic address: xiangweifu@126.com.
authors.forename: Xiangwei
authors.initials: X
authors.lastname: Fu
authors.affiliation: Laboratory of Animal Embryonic Biotechnology, College of Animal Science and Technology, China Agricultural University, Beijing, P.R. China. Electronic address: zhushien@cau.edu.cn.
authors.forename: Shien
authors.initials: S
authors.lastname: Zhu
mesh_terms: D000782:Aneuploidy; D000818:Animals; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002503:Centromere / Q000502:physiology; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D015925:Cryopreservation / Q000379:methods / Q000662:veterinary*; D008677:Metaphase; D051379:Mice; D009865:Oocytes / Q000648:ultrastructure*; D012333:RNA, Messenger / Q000378:metabolism; D058989:Vitrification; D000097722:Cohesins
chemical_list: D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D012333:RNA, Messenger; D000097722:Cohesins
keywords: Aneuploidy; Cohesin; Mouse; Oocyte; Vitrification