Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Editor

Personal info

View

About

Terms

Javascript disabled

Please enable Javascript support in your browser to use this application.

Instructions on how to enable JavaScript on different browsers can be found here: http://www.google.com/support/bin/answer.py?answer=23852.

[edit this page]

Maddox, P.S. et al.

The minus end-directed motor Kar3 is required for coupling dynamic microtubule plus ends to the cortical shmoo tip in budding yeast.

The budding yeast shmoo tip is a model system for analyzing mechanisms coupling force production to microtubule plus-end polymerization/depolymerization. Dynamic plus ends of astral microtubules interact with the shmoo tip in mating yeast cells, positioning nuclei for karyogamy. We have used live-cell imaging of GFP fusions to identify proteins that couple dynamic microtubule plus ends to the shmoo tip. We find that Kar3p, a minus end-directed kinesin motor protein, is required, whereas the other cytoplasmic motors, dynein and the kinesins Kip2p and Kip3p, are not. In the absence of Kar3p, attached microtubule plus ends released from the shmoo tip when they switched to depolymerization. Furthermore, microtubules in cells expressing kar3-1, a mutant that results in rigor binding to microtubules [2], were stabilized specifically at shmoo tips. Imaging of Kar3p-GFP during mating revealed that fluorescence at the shmoo tip increased during periods of microtubule depolymerization. These data are the first to localize the activity of a minus end-directed kinesin at the plus ends of microtubules. We propose a model in which Kar3p couples depolymerizing microtubule plus ends to the cell cortex and the Bim1p-Kar9p protein complex maintains attachment during microtubule polymerization. In support of this model, analysis of Bim1p-GFP at the shmoo tip results in a localization pattern complementary to that of Kar3p-GFP.[1]

References

The minus end-directed motor Kar3 is required for coupling dynamic microtubule plus ends to the cortical shmoo tip in budding yeast. Maddox, P.S., Stemple, J.K., Satterwhite, L., Salmon, E.D., Bloom, K. Curr. Biol. (2003) [Pubmed]

Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenes Open Access Licence Privacy Policy Terms of Use apsburg

The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.