RanGTP and CLASP1 cooperate to position the mitotic spindle

Bird, Stephen L.; Heald, Rebecca; Weis, Karsten

doi:10.1091/mbc.e13-03-0150

Cited by 33 publications

(33 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Here, uniformly high RanGTP levels result in ectopic microtubule polymerisation [23], as well as spindle assembly and chromosome alignment delays [72]. Similarly, inhibition of RanGTP results in spindle defects, aberrant chromosome alignment, spindle positioning defects and defects in kinetochore microtubule formation following nocodazole washout [23,62,[73][74][75]. In agreement with these results, a steep mitotic RanGTP gradient can be detected in many cell lines such as HeLa cells, although other cell lines, and particularly untransformed ones, often do not show clear gradients [72].…”

Section: Does Chromosome-induced Microtubule Polymerisation Contributmentioning

confidence: 98%

Nucleosome functions in spindle assembly and nuclear envelope formation

Zierhut

2015

BioEssays

View full text Add to dashboard Cite

Summary Chromosomes are not only carriers of the genetic material, but also actively regulate the assembly of complex intracellular architectures. During mitosis, chromosome-induced microtubule polymerisation ensures spindle assembly in cells without centrosomes and plays a supportive role in centrosome-containing cells. Chromosomal signals also mediate post-mitotic nuclear envelope (NE) re-formation. Recent studies using novel approaches to manipulate histones in oocytes, where functions can be analysed in the absence of transcription, have established that nucleosomes, but not DNA alone, mediate the chromosomal regulation of spindle assembly and NE formation. Both processes require the generation of RanGTP by RCC1 recruited to nucleosomes but nucleosomes also acquire cell cycle stage specific regulators, Aurora B in mitosis and ELYS, the initiator of nuclear pore complex assembly, at mitotic exit. Here, we review the mechanisms by which nucleosomes control assembly and functions of the spindle and the NE, and discuss their implications for genome maintenance.

show abstract

Section: Does Chromosome-induced Microtubule Polymerisation Contributmentioning

confidence: 98%

Nucleosome functions in spindle assembly and nuclear envelope formation

Zierhut

2015

BioEssays

View full text Add to dashboard Cite

show abstract

“…It was postulated that the association of RCC1 with mitotic chromatin establishes a local RanGTP gradient in anaphase that is high at cell poles and low at the cell centre. RanGTP then functions via importinβ to influ ence the activity and/or localization of a wide range of actin regulators that carry an NLS (nuclear localization signal) 111,114 . These include Anillin 115 , which is lost from the polar cortex following the approach of chromo somes 112 , leading to weakening of the mitotic cortical actomyosin network (as is the case during meiosis) 116 .…”

Section: Midbodymentioning

confidence: 99%

Coupling changes in cell shape to chromosome segregation

Ramkumar

Baum

2016

Nat Rev Mol Cell Biol

129

132

View full text Add to dashboard Cite

Animal cells undergo dramatic changes in shape, mechanics and polarity as they progress through the different stages of cell division. These changes begin at mitotic entry, with cell-substrate adhesion remodelling, assembly of a cortical actomyosin network and osmotic swelling, which together enable cells to adopt a near spherical form even when growing in a crowded tissue environment. These shape changes, which probably aid spindle assembly and positioning, are then reversed at mitotic exit to restore the interphase cell morphology. Here, we discuss the dynamics, regulation and function of these processes, and how cell shape changes and sister chromatid segregation are coupled to ensure that the daughter cells generated through division receive their fair inheritance.

show abstract

“…Spindle size may be directly dictated by the physical dimensions of a cell, perhaps through microtubule-mediated interaction with the cell cortex [i.e. boundary sensing; (5–7)]. Alternatively, cell size could constrain spindle length by providing a fixed and finite cytoplasmic volume and, therefore, a limiting pool of resources such as cytoplasmic spindle assembly or length-determining components [i.e.…”

mentioning

confidence: 99%

Changes in Cytoplasmic Volume Are Sufficient to Drive Spindle Scaling

Hazel

Krutkramelis

Mooney

et al. 2013

Science

184

195

View full text Add to dashboard Cite

The mitotic spindle must function in cell types that vary greatly in size, and its dimensions scale with the rapid, reductive cell divisions that accompany early stages of development. The mechanism responsible for this scaling is unclear, because uncoupling cell size from a developmental or cellular context has proven experimentally challenging. Here we combined microfluidic technology with Xenopus egg extracts to characterize spindle assembly within discrete, geometrically defined volumes of cytoplasm. Reductions in cytoplasmic volume, rather than developmental cues or changes in cell shape, were sufficient to recapitulate spindle scaling observed in Xenopus embryos. Thus, mechanisms extrinsic to the spindle, specifically a limiting pool of cytoplasmic component(s), play a major role in determining spindle size.

show abstract

RanGTP and CLASP1 cooperate to position the mitotic spindle

Cited by 33 publications

References 43 publications

Nucleosome functions in spindle assembly and nuclear envelope formation

Nucleosome functions in spindle assembly and nuclear envelope formation

Coupling changes in cell shape to chromosome segregation

Changes in Cytoplasmic Volume Are Sufficient to Drive Spindle Scaling

Contact Info

Product

Resources

About