SOLUBILIZATION OF ASTER-FORMING PROTEINS FROM YEAST - POSSIBLE CONSTITUENTS OF SPINDLE POLE BODY AND RECONSTITUTION OF ASTERS INVITRO

被引:5
作者
YAMAMOTO, A
NAGAI, K
YAMASAKI, M
MATSUHASHI, M
机构
[1] UNIV TOKYO, DEPT AGR CHEM, BUNKYO KU, TOKYO 113, JAPAN
[2] UNIV TOKYO, INST TECHNOL, DEPT BIOENGN, MEGURO KU, TOKYO 152, JAPAN
关键词
aster; microtubules; Saccharomyces cerevisiae; spindle pole body;
D O I
10.1247/csf.15.221
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Spindle pole bodies (SPBs) attached to nuclei were isolated from Saccharomyces cerevisiae; they nucleated microtubules to form asters in vitro. This aster-forming activity was stable in 30% dimethylsulfoxide or 10% 2-propanol and could be solubilized with KCl. The KCl extract contained many protein components, which aggregated upon dialysis against a low concentration salt solution. When incubated with tubulin, the aggregates formed asters. Measurements of the elongation rates of the astral microtubules indicated that the microtubules were nucleated from the SPBs or from the aggregates reconstructed from the KCl extract by dialysis. The plus end was distal to the astral center, as in the case of the microtubule organizing center (MTOC) of mammalian cells. We suggest that the proteins extracted with KCl are responsible for microtubule nucleation in SPBs and that this SPB seems to have the same mechanism for microtubule nucleation as the MTOC in higher eukaryotes. © 1990, Japan Society for Cell Biology. All rights reserved.
引用
收藏
页码:221 / 228
页数:8
相关论文
共 24 条