title: Oocyte maturation-related gene expression in the canine oviduct, cumulus cells, and oocytes and effect of co-culture with oviduct cells on in vitro maturation of oocytes.
abstract: OBJECTIVE
  In contrast to most other mammals, canine oocytes are ovulated in an immature state and undergo oocyte maturation within the oviduct during the estrus stage. The aim of the study was to investigate whether oviduct cells from the estrus stage affect the maturation of oocytes and show gene expression patterns related to oocyte maturation.
  
  
  METHODS
  We analyzed MAPK1/3, SMAD2/3, and BMP6/15 expression in oviduct cells, cumulus cells, and oocytes from anestrus, estrus, and diestrus stages. Next, we investigated the effect of co-culture with oviduct cells derived from the estrus stage upon in vitro maturation (IVM) of canine oocytes.
  
  
  RESULTS
  There was significantly higher MAPK1/3 (1.42 ± 0.02 and 2.23 ± 0.06), SMAD2/3 (0.77 ± 0.03 and 2.39 ± 0.07), and BMP15 (2.21 ± 0.16) expression in oviduct cells at the estrus stage (P < 0.05). In cumulus cells, MAPK1 (1.26 ± 0.07), SMAD2/3 (0.82 ± 0.01, 1.04 ± 0.01), and BMP6 (13.09 ± 0.11) expression was significantly higher in the estrus stage (P < 0.05). In oocytes, significant upregulation of MAPK1/3 (14,960 ± 3121 and 1668 ± 253.4), SMAD3 (774.6 ± 79.62), and BMP6 (8500 ± 895.4) expression was found in the estrus stage (P < 0.05). After 72 h of IVM culture, a significantly higher maturation rate was observed in oocytes co-cultured with oviduct cells (10.0 ± 1.5%) than in the control group (3.2 ± 1.4%).
  
  
  CONCLUSIONS
  We demonstrate that oviduct cells at the estrus stage highly expressed MAPK1/3, SMAD2/3, and BMP15. Furthermore, canine oviduct cells from the estrus stage enhance the culture environment for canine oocyte maturation.
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Seok Hee
authors.initials: SH
authors.lastname: Lee
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Hyun Ju
authors.initials: HJ
authors.lastname: Oh
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Kim
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Geon A
authors.initials: GA
authors.lastname: Kim
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Yoo Bin
authors.initials: YB
authors.lastname: Choi
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Young Kwang
authors.initials: YK
authors.lastname: Jo
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea.
authors.forename: Erif Maha Nugraha
authors.initials: EMN
authors.lastname: Setyawan
authors.affiliation: Department of Theriogenology and Biotechnology, College of Veterinary Medicine, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea. bclee@snu.ac.kr.
authors.forename: Byeong Chun
authors.initials: BC
authors.lastname: Lee
mesh_terms: D000818:Animals; D018920:Coculture Techniques; D054885:Cumulus Cells / Q000378:metabolism; D004285:Dogs; D004971:Estrus / Q000378:metabolism; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary; D020869:Gene Expression Profiling / Q000662:veterinary; D059471:In Vitro Oocyte Maturation Techniques / Q000662:veterinary; D020935:MAP Kinase Signaling System; D009865:Oocytes / Q000254:growth & development / Q000378:metabolism*; D010057:Oviducts / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism
chemical_list: D012333:RNA, Messenger
keywords: Co-culture; Estrus stage; Gene expression; In vitro maturation; Oocyte; Oviduct cell