Linked Life Data

18722122

Source:http://linkedlifedata.com/resource/pubmed/id/18722122

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
16
pubmed:dateCreated
2008-8-27
pubmed:abstractText
During mitosis, the kinetochore microtubules capture and segregate chromosomes, and the astral microtubules position the spindle within the cell. Although the spindle is symmetric, proper positioning of the spindle in asymmetrically dividing cells generally correlates with the formation of morphologically and structurally distinct asters [1]. In budding yeast, the spindle-orientation proteins Kar9 and dynein decorate only one aster of the metaphase spindle and direct it toward the bud [2, 3]. The mechanisms controlling the distribution of Kar9 and dynein remain unclear. Here, we show that SUMO regulates astral-microtubule function in at least two ways. First, Kar9 was sumoylated in vivo. Sumoylation and Cdk1-dependent phosphorylation of Kar9 independently promoted Kar9 asymmetry on the spindle. Second, proper regulation of kinetochore function by SUMO was also required for Kar9 asymmetry. Indeed, activation of the spindle-assembly checkpoint (SAC) due to SUMO and kinetochore defects promoted symmetric redistribution of Kar9 in a Mad2-dependent manner. The control of Kar9 distribution by the SAC was independent of Kar9 sumoylation and phosphorylation. Together, our data reveal that three independent mechanisms contribute to Kar9 asymmetry: Cdk1-dependent phosphorylation, sumoylation, and SAC signaling. Hence, the two seemingly independent spindle domains, kinetochores and astral microtubules, function in a tightly coordinated fashion.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0960-9822
pubmed:author
pubmed:issnType
Print
pubmed:day
26
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1249-55
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2008
pubmed:articleTitle
Regulation of mitotic spindle asymmetry by SUMO and the spindle-assembly checkpoint in yeast.
pubmed:affiliation
Institute of Biochemistry, Department of Biology, Swiss Federal Institute of Technology, Schafmattstrasse 18, 8093 Zurich, Switzerland.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't