Related Experiment Video
Updated: May 8, 2026

Proteomics to Identify Proteins Interacting with P2X2 Ligand-Gated Cation Channels
Published on: May 19, 2009
Xklp2, a novel Xenopus centrosomal kinesin-like protein required for centrosome separation during mitosis
H Boleti1, E Karsenti, I Vernos
1Cell Biology Programme, European Molecular Biology Laboratory, Heidelberg, Federal Republic of Germany.
Abstract:
We describe a novel Xenopus plus end-directed kinesin-like protein (KLP), Xklp2, localized on centrosomes throughout the cell cycle and on spindle pole microtubules during metaphase. Using mitotic spindles assembled in Xenopus egg extracts and different recombinant GST-Xklp2 mutants, we show that this motor is targeted to spindle poles through its C-terminal domain. Xklp2-truncated polypeptides lacking the motor domain block centrosome separation and disrupt preassembled metaphase spindles. Antibodies directed against the tail of Xklp2 have a similar effect. These results show that Xklp2 protein is required for centrosome separation and maintenance of spindle bipolarity. This study is an example of the application of the dominant negative mutant effect on spindle assembly in Xenopus egg extracts, demonstrating the usefulness of this approach in probing the function of proteins in this system.
Related Concept Videos
X-Inactivation
Inheritance of Chromatin Structures
Destabilization of Microtubules
Translocation of Proteins into the Mitochondria
Sorting of outer membrane proteins:
Mitochondrial outer membrane proteins are of two types: the transmembrane, beta-barrel porins, and the membrane-anchored, alpha-helical proteins. Beta-barrel porin precursors are translocated by the TOM complex and inserted into the outer mitochondrial membrane by the SAM complex. In contrast,...
X-inactivation
The Mitotic Spindle
The bipolar configuration of the mitotic spindle facilitates chromosomal segregation, preparing the cell for division. One mechanism that ensures bipolar mitotic...

