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J Cell Biol
2006 Jun 19;1736:829-31. doi: 10.1083/jcb.200605150.
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"HURP on" we're off to the kinetochore!
Wilde A
.
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RanGTP has a central role in spindle assembly, but the Ran-regulated factors required to initiate spindle bipolarity and stabilize MT growth toward the chromosomes remain unknown. However, three recent papers (Koffa et al., 2006; Sillje et al., 2006; Wong and Fang, 2006) have identified a single factor, HURP, that may encompass both of these properties.
Figure 1. HURP (red) is involved in stabilizing and targeting K-fibers to chromosomes (blue). Depletion of HURP leads to unstable K-fibers, which either fail to attach to kinetochores (black) or fail to generate tension between sister kinetochores; yet these cells eventually enter anaphase. Yellow depicts the gradient of RanGTP emanating from the chromosomes.
Figure 2. Model for the potential mode of action of the HURP complex. The components of the complex assemble in an MT-dependent or -independent manner. Once formed, Aurora A can phosphorylate components of the complex (arrows lead to known substrates of Aurora A). The complex may then function as a single entity or dissociate into smaller units to carry out specific functions in different parts of the spindle.
Caudron,
Spatial coordination of spindle assembly by chromosome-mediated signaling gradients.
2005, Pubmed,
Xenbase
Caudron,
Spatial coordination of spindle assembly by chromosome-mediated signaling gradients.
2005,
Pubmed
,
Xenbase
Gadde,
Mechanisms and molecules of the mitotic spindle.
2004,
Pubmed
Hetzer,
The Ran GTPase as a marker of chromosome position in spindle formation and nuclear envelope assembly.
2002,
Pubmed
Kaláb,
Analysis of a RanGTP-regulated gradient in mitotic somatic cells.
2006,
Pubmed
,
Xenbase
Koffa,
HURP is part of a Ran-dependent complex involved in spindle formation.
2006,
Pubmed
,
Xenbase
Li,
Phosphorylation of RCC1 in mitosis is essential for producing a high RanGTP concentration on chromosomes and for spindle assembly in mammalian cells.
2004,
Pubmed
,
Xenbase
Schatz,
Importin alpha-regulated nucleation of microtubules by TPX2.
2003,
Pubmed
,
Xenbase
Silljé,
HURP is a Ran-importin beta-regulated protein that stabilizes kinetochore microtubules in the vicinity of chromosomes.
2006,
Pubmed
Silverman-Gavrila,
Ran is required before metaphase for spindle assembly and chromosome alignment and after metaphase for chromosome segregation and spindle midbody organization.
2006,
Pubmed
Trieselmann,
Ran modulates spindle assembly by regulating a subset of TPX2 and Kid activities including Aurora A activation.
2003,
Pubmed
,
Xenbase
Tsai,
A Ran signalling pathway mediated by the mitotic kinase Aurora A in spindle assembly.
2003,
Pubmed
,
Xenbase
Tulu,
Molecular requirements for kinetochore-associated microtubule formation in mammalian cells.
2006,
Pubmed
Wilde,
Ran stimulates spindle assembly by altering microtubule dynamics and the balance of motor activities.
2001,
Pubmed
,
Xenbase
Wollman,
Efficient chromosome capture requires a bias in the 'search-and-capture' process during mitotic-spindle assembly.
2005,
Pubmed
Wong,
HURP controls spindle dynamics to promote proper interkinetochore tension and efficient kinetochore capture.
2006,
Pubmed
Yu,
Phosphorylation and stabilization of HURP by Aurora-A: implication of HURP as a transforming target of Aurora-A.
2005,
Pubmed
