TY - JOUR
T1 - Quantitative analysis in LC3-II protein in vitro maturation of porcine oocyte
AU - Lee, Seung Hoon
AU - Hiradate, Yuuki
AU - Hoshino, Yumi
AU - Tanemura, Kentaro
AU - Sato, Eimei
PY - 2014/8
Y1 - 2014/8
N2 - Summary Microtubule-associated protein light chain 3 (LC3)-II is a marker of autophagosome. In this study, LC3-II expression was used to identify autophagy, during the in vitro maturation of porcine oocytes. In a time-course experiment, cumulus-oocyte complexes (COCs) were cultured in NCSU23 medium for 0 h, 14 h, 28 h or 42 h. The cumulus cells were removed and denuded oocytes were processed for western blotting or immunostaining. Western blotting showed that the LC3-II levels changed over time, with maximum levels observed at 14 h and minimum levels at 42 h. Immunostaining of LC3 showed the signals with dot shapes and ring shapes in oocytes at every group that probably represent autophagosomes. To ascertain whether autophagic induction and degradation were occurring, we treated the cultures with autophagic inhibitors. Lysosomal protease inhibitor E64d and pepstatin A increased the LC3-II levels and wortmannin, inhibitor of autophagic induction, decreased the LC3-II levels. Western blotting and immunostaining demonstrated that LC3-II is present in porcine oocytes cultured in vitro. The decreased LC3-II levels after wortmannin treatment suggest that it is newly generated in porcine oocytes, a phenomenon that represents autophagic induction. Furthermore, increased LC3-II levels after E64d and pepstatin A addition imply that LC3-II is degraded by lysosomal proteases, an indication of autophagic degradation. Our results suggest that autophagy, which is a dynamic process whereby autophagosomes are newly generated and subsequently degraded, is probably occurring in porcine oocytes during in vitro maturation.
AB - Summary Microtubule-associated protein light chain 3 (LC3)-II is a marker of autophagosome. In this study, LC3-II expression was used to identify autophagy, during the in vitro maturation of porcine oocytes. In a time-course experiment, cumulus-oocyte complexes (COCs) were cultured in NCSU23 medium for 0 h, 14 h, 28 h or 42 h. The cumulus cells were removed and denuded oocytes were processed for western blotting or immunostaining. Western blotting showed that the LC3-II levels changed over time, with maximum levels observed at 14 h and minimum levels at 42 h. Immunostaining of LC3 showed the signals with dot shapes and ring shapes in oocytes at every group that probably represent autophagosomes. To ascertain whether autophagic induction and degradation were occurring, we treated the cultures with autophagic inhibitors. Lysosomal protease inhibitor E64d and pepstatin A increased the LC3-II levels and wortmannin, inhibitor of autophagic induction, decreased the LC3-II levels. Western blotting and immunostaining demonstrated that LC3-II is present in porcine oocytes cultured in vitro. The decreased LC3-II levels after wortmannin treatment suggest that it is newly generated in porcine oocytes, a phenomenon that represents autophagic induction. Furthermore, increased LC3-II levels after E64d and pepstatin A addition imply that LC3-II is degraded by lysosomal proteases, an indication of autophagic degradation. Our results suggest that autophagy, which is a dynamic process whereby autophagosomes are newly generated and subsequently degraded, is probably occurring in porcine oocytes during in vitro maturation.
KW - Autophagy
KW - Autophagy inhibitor
KW - In vitro maturation
KW - LC3
KW - Porcine oocyte
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U2 - 10.1017/S0967199413000269
DO - 10.1017/S0967199413000269
M3 - Article
C2 - 23759564
AN - SCOPUS:84903454022
VL - 22
SP - 404
EP - 410
JO - Zygote
JF - Zygote
SN - 0967-1994
IS - 3
ER -