Take our Survey

Reference: Cuschieri L, et al. (2006) {gamma}-Tubulin Is Required for Proper Recruitment and Assembly of Kar9-Bim1 Complexes in Budding Yeast. Mol Biol Cell 17(10):4420-34

Reference Help

Abstract


Monitoring Editor: Kerry Bloom Microtubule +end interacting proteins (+TIPs) promote the dynamic interactions between the +ends of astral microtubules and cortical actin that are required for pre-anaphase spindle positioning. Paradoxically, +TIPs such as the EB1 ortholog Bim1 and Kar9 also associate with spindle pole bodies (SPBs), the centrosome equivalent in budding yeast. Here, we show that deletion of 4 c-terminal residues of the budding yeast gamma-tubulin Tub4 (tub4-Deltadsyl) perturbs Bim1 and Kar9 localization to SPBs and Kar9-dependant spindle positioning. Surprisingly, we find Kar9 localizes to microtubule +ends in tub4-Deltadsyl cells, but these microtubules fail to position the spindle when targeted to the bud. Using cofluorescence and coaffinity purification, we show Kar9 complexes in tub4-Deltadsyl cells contain reduced levels of Bim1. Astral microtubule dynamics are suppressed in tub4-Deltadsyl cells, but are restored by deletion of Kar9. Moreover, Myo2 and F-actin dependant dwelling of Kar9 in the bud is observed in tub4-Deltadsyl cells, suggesting defective Kar9 complexes tether microtubule +ends to the cortex. Overproduction of Bim1, but not Kar9, restores Kar9-dependent spindle positioning in the tub4-Deltadsyl mutant, reduces cortical dwelling and promotes Bim1-Kar9 interactions. We propose that SPBs, via the tail of Tub4, promote the assembly of functional +TIP complexes before their deployment to microtubule +ends.

Reference Type
Journal Article
Authors
Cuschieri L, Miller R, Vogel J
Primary Lit For
Additional Lit For
Review For

Interaction Annotations


Increase the total number of rows showing on this page by using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details about experiment type and any other genes involved in the interaction.

Interactor Interactor Type Assay Annotation Action Modification Phenotype Source Reference

Gene Ontology Annotations


Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table.

Gene Gene Ontology Term Qualifier Aspect Method Evidence Source Assigned On Annotation Extension Reference

Phenotype Annotations


Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details.

Gene Phenotype Experiment Type Mutant Information Strain Background Chemical Details Reference

Regulation Annotations


Increase the total number of rows displayed on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; to filter the table by a specific experiment type, type a keyword into the Filter box (for example, “microarray”); download this table as a .txt file using the Download button or click Analyze to further view and analyze the list of target genes using GO Term Finder, GO Slim Mapper, SPELL, or YeastMine.

Regulator Target Experiment Assay Construct Conditions Strain Background Reference