Unlike somatic cells mitosis, germ cell meiosis consists of two consecutive rounds of divisions that segregate homologous chromosomes and sister chromatids, respectively. The meiotic oocyte is characterized by an absence of centrioles and asymmetric divisions. Centriolin is a relatively novel centriolar protein that functions in mitotic cell cycle progression and cytokinesis. Here, we explored the function of centriolin in meiosis and showed that it was localized to meiotic spindles, and concentrated at the spindle poles and midbody during oocyte meiotic maturation. Unexpectedly, knockdown of centriolin in oocytes with either siRNA or Morpholino micro-injection, did not affect meiotic spindle organization, cell cycle progression, or cytokinesis (as indicated by polar body emission), but led to a failure of peripheral meiotic spindle migration; and symmetric division or large polar body emission. These data suggest that, unlike in mitotic cells, the centriolar protein centriolin does not regulate cytokinesis, but plays an important role in regulating asymmetric division of meiotic oocytes.

• Tian-Yi Sun(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• Hai-Yang Wang(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• JeongWoo Kwon(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• Bao Yuan(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• In-Won Lee(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• Xiang-Shun Cui(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)
• Nam-Hyung Kim(Department of Animal Sciences, Chungbuk National University, Brain Korea 21 center for Bio-Resource Development, Chungbuk National University, South Korea)