Axin-1 Regulates Meiotic Spindle Organization in Mouse Oocytes.
Axin-1, a negative regulator of Wnt signaling, is a versatile scaffold protein involved in centrosome separation and spindle assembly in mitosis, but its function in mammalian oogenesis remains unknown. Here we examined the localization and function of Axin-1 during meiotic maturation in mouse oocytes. Immunofluorescence analysis showed that Axin-1 was localized around the spindle. Knockdown of the Axin1 gene by microinjection of specific short interfering (si)RNA into the oocyte cytoplasm resulted in severely defective spindles, misaligned chromosomes, failure of first polar body (PB1) extrusion, and impaired pronuclear formation. However, supplementing the culture medium with the Wnt pathway activator LiCl improved spindle morphology and pronuclear formation. Downregulation of Axin1 gene expression also impaired the spindle pole localization of γ-tubulin/Nek9 and resulted in retention of the spindle assembly checkpoint protein BubR1 at kinetochores after 8.5 h of culture. Our results suggest that Axin-1 is critical for spindle organization and cell cycle progression during meiotic maturation in mouse oocytes.
Organ Transplantation Institute, Medical College, Xiamen University, Xiamen City, Fujian Province, P. R. China.|Department of Gynaecology and Obstetrics, Zhongshan Hospital, Xiamen University, Xiamen City, Fujian Province, P. R. China.|The Fifth Hospital of Wuhan, Wuhan City, Hubei Province, P. R. China.
Xiao-Qin
XQ
He
New England Fertility Institute, Stamford, CT, United States of America.
Yue-Qiang
YQ
Song
Department of Gynaecology and Obstetrics, Zhongshan Hospital, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Rui
R
Liu
Organ Transplantation Institute, Medical College, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Yu
Y
Liu
Department of Gynaecology and Obstetrics, Zhongshan Hospital, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Fei
F
Zhang
Xiamen Institute for Food and Drug Quality Control, Xiamen City, Fujian Province, P. R. China.
Zhen
Z
Zhang
Department of Obstetrics and Gynecology, Shanghai First Maternity and Infant Hospital, Tongji University School of Medicine, Shanghai City, P. R. China.
Yu-Ting
YT
Shen
New England Fertility Institute, Stamford, CT, United States of America.
Lin
L
Xu
Department of Gynaecology and Obstetrics, Zhongshan Hospital, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Ming-Huang
MH
Chen
Organ Transplantation Institute, Medical College, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Ya-Long
YL
Wang
Organ Transplantation Institute, Medical College, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Bai-Hui
BH
Xu
Department of Gynaecology and Obstetrics, Zhongshan Hospital, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Xiang-Jun
XJ
Yang
Organ Transplantation Institute, Medical College, Xiamen University, Xiamen City, Fujian Province, P. R. China.
Hai-Long
HL
Wang
D000818:Animals; D060466:Axin Protein / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D018797:Cell Cycle Proteins / Q000032:analysis / Q000378:metabolism; D002478:Cells, Cultured; D005260:Female; D008540:Meiosis; D051379:Mice; D000072379:NIMA-Related Kinases / Q000032:analysis / Q000378:metabolism; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism; D009866:Oogenesis; D017346:Protein Serine-Threonine Kinases / Q000032:analysis / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D008941:Spindle Apparatus / Q000235:genetics / Q000378:metabolism / Q000648:ultrastructure*; D014404:Tubulin / Q000032:analysis / Q000378:metabolism
D060466:Axin Protein; C555452:Axin1 protein, mouse; C584278:Bub1b protein, mouse; D018797:Cell Cycle Proteins; D034741:RNA, Small Interfering; C583407:TUBG1 protein, mouse; D014404:Tubulin; D000072379:NIMA-Related Kinases; C581080:Nek9 protein, mouse; D017346:Protein Serine-Threonine Kinases