Unified mode of centromeric protection by shugoshin in mammalian oocytes and somatic cells.
Reductional chromosome segregation in germ cells, where sister chromatids are pulled to the same pole, accompanies the protection of cohesin at centromeres from separase cleavage. Here, we show that mammalian shugoshin Sgo2 is expressed in germ cells and is solely responsible for the centromeric localization of PP2A and the protection of cohesin Rec8 in oocytes, proving conservation of the mechanism from yeast to mammals. However, this role of Sgo2 contrasts with its mitotic role in protecting centromeric cohesin only from prophase dissociation, but never from anaphase cleavage. We demonstrate that, in somatic cells, shugoshin colocalizes with cohesin in prophase or prometaphase, but their localizations become separate when centromeres are pulled oppositely at metaphase. Remarkably, if tension is artificially removed from the centromeres at the metaphase-anaphase transition, cohesin at the centromeres can be protected from separase cleavage even in somatic cells, as in germ cells. These results argue for a unified view of centromeric protection by shugoshin in mitosis and meiosis.
Lee
Jibak
J
Laboratory of Reproductive Biology and Biotechnology, Graduate School of Science and Technology, Kobe University, Kobe 657-8501, Japan.
Kitajima
Tomoya S
TS
Tanno
Yuji
Y
Yoshida
Kayo
K
Morita
Takashi
T
Miyano
Takashi
T
Miyake
Masashi
M
Watanabe
Yoshinori
Y
D000818:Animals; D015152:Blotting, Northern; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000378:metabolism; D002478:Cells, Cultured; D002503:Centromere / Q000378:metabolism*; D002842:Chromatids / Q000378:metabolism; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D005260:Female; D020869:Gene Expression Profiling; D006367:HeLa Cells; D006801:Humans; D007150:Immunohistochemistry; D018386:Kinetochores / Q000378:metabolism; D008297:Male; D008677:Metaphase / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008938:Mitosis / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D010750:Phosphoproteins / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012854:Sister Chromatid Exchange; D000097722:Cohesins
D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D009687:Nuclear Proteins; D010750:Phosphoproteins; D034741:RNA, Small Interfering; D000097722:Cohesins; C465863:Rec8 protein, mouse; C527733:shugoshin protein, mouse