Association of polo-like kinase with alpha-, beta- and gamma-tubulins in astable complex

Citation
Y. Feng et al., Association of polo-like kinase with alpha-, beta- and gamma-tubulins in astable complex, BIOCHEM J, 339, 1999, pp. 435-442
Citations number
37
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Biochemistry & Biophysics
Journal title
BIOCHEMICAL JOURNAL
ISSN journal
0264-6021 → ACNP
Volume
339
Year of publication
1999
Part
2
Pages
435 - 442
Database
ISI
SICI code
0264-6021(19990415)339:<435:AOPKWA>2.0.ZU;2-6
Abstract
The polo-like kinase (Plk) family has been shown to have an important role in the regulation of the cell-division cycle, especially in organization of the spindle structure, in species from fungi to humans. Recent reports hav e demonstrated that in mammalian cells Plk is associated with components of the anaphase-promoting complex and a peptidyl-prolyl isomerase, Pin1. To c haracterize a putative Plk-containing complex, we fractionated mitotic cell lysates on a gel-filtration column. The Plk complex was eluted from the co lumn at molecular sizes ranging from 669 to 2500 kDa in the presence of det ergent and high concentrations of salt, Specific associations of Plk with a lpha-, beta- and gamma-tubulins in both interphase and mitotic cells were s hown by reciprocal immunoprecipitations and immunoblottings and were indepe ndent of the microtubule polymerization state, whereas binding assays in vi tro indicated that Plk interacts with alpha- and beta-tubulins directly. In addition, mitotic Plk was able to phosphorylate associated tubulins in vit ro. Finally, we show that the kinase domain of the Plk molecule is both req uired and sufficient for its binding to tubulins in vivo. The specific inte raction between Plk and tubulins might provide a molecular basis for the ph ysiological functions of Plk in regulating the cell cycle, particularly in establishing the normal bipolar spindle.