Control of microtubule dynamics by the antagonistic activities of XMAP215 and XKCM1 in Xenopus egg extracts.
Microtubules are dynamic polymers that move stochastically between periods of growth and shrinkage, a property known as dynamic instability. Here, to investigate the mechanisms regulating microtubule dynamics in Xenopus egg extracts, we have cloned the complementary DNA encoding the microtubule-associated protein XMAP215 and investigated the function of the XMAP215 protein. Immunodepletion of XMAP215 indicated that it is a major microtubule-stabilizing factor in Xenopus egg extracts. During interphase, XMAP215 stabilizes microtubules primarily by opposing the activity of the destabilizing factor XKCM1, a member of the kinesin superfamily. These results indicate that microtubule dynamics in Xenopus egg extracts are regulated by a balance between a stabilizing factor, XMAP215, and a destabilizing factor, XKCM1.
Tournebize
R
R
Cell Biology Program, EMBL, Meyerhofstrasse 1, 69117 Heidelberg, Germany.
Popov
A
A
Kinoshita
K
K
Ashford
A J
AJ
Rybina
S
S
Pozniakovsky
A
A
Mayer
T U
TU
Walczak
C E
CE
Karsenti
E
E
Hyman
A A
AA
D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D019143:Evolution, Molecular; D019084:Fluorescent Antibody Technique, Indirect; D016547:Kinesins / Q000235:genetics / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism*; D008938:Mitosis / Q000235:genetics; D008969:Molecular Sequence Data; D009865:Oocytes / Q000378:metabolism*; D010802:Phylogeny; D011817:Rabbits; D017386:Sequence Homology, Amino Acid; D008941:Spindle Apparatus / Q000502:physiology; D014981:Xenopus; D029867:Xenopus Proteins
C486738:CKAP5 protein, Xenopus; D018076:DNA, Complementary; C088335:KIF11 protein, Xenopus; D008869:Microtubule-Associated Proteins; D029867:Xenopus Proteins; D016547:Kinesins