CENP-E is an essential kinetochore motor in maturing oocytes and is masked during mos-dependent, cell cycle arrest at metaphase II.
CENP-E, a kinesin-like protein that is known to associate with kinetochores during all phases of mitotic chromosome movement, is shown here to be a component of meiotic kinetochores as well. CENP-E is detected at kinetochores during metaphase I in both mice and frogs, and, as in mitosis, is relocalized to the midbody during telophase. CENP-E function is essential for meiosis I because injection of an antibody to CENP-E into mouse oocytes in prophase completely prevented progression of those oocytes past metaphase I. Beyond this, CENP-E is modified or masked during the natural, Mos-dependent, cell cycle arrest that occurs at metaphase II, although it is readily detectable at the kinetochores in metaphase II oocytes derived from mos-deficient (MOS-/-) mice that fail to arrest at metaphase II. This must reflect a masking of some CENP-E epitopes, not the absence of CENP-E, in meiosis II because a different polyclonal antibody raised to the tail of CENP-E detects CENP-E at kinetochores of metaphase II-arrested eggs and because CENP-E reappears in telophase of mouse oocytes activated in the absence of protein synthesis.
Duesbery
N S
NS
ABL-Basic Research Program, National Cancer Institute-Frederick Cancer Research and Development Center, P.O. Box B, Frederick, MD 21702-1201, USA.
Choi
T
T
Brown
K D
KD
Wood
K W
KW
Resau
J
J
Fukasawa
K
K
Cleveland
D W
DW
Vande Woude
G F
GF
D000818:Animals; D002453:Cell Cycle; D002454:Cell Differentiation; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D005260:Female; D016258:Genes, mos; D018386:Kinetochores / Q000378:metabolism*; D008677:Metaphase; D051379:Mice; D009865:Oocytes / Q000166:cytology / Q000378:metabolism*; D011247:Pregnancy; D014982:Xenopus laevis
D002868:Chromosomal Proteins, Non-Histone; C068688:centromere protein E