scholarly journals Mad1p, a component of the spindle assembly checkpoint in fission yeast, suppresses a novel septation-defective mutant,sun1, in a cell-division cycle

2003 ◽  
Vol 227 (2) ◽  
pp. 183-188 ◽  
Author(s):  
In G Kim ◽  
Dong K Rhee ◽  
Jae W Jeong ◽  
Seong C Kim ◽  
Misun Won ◽  
...  
Keyword(s):  
Cell Division ◽  
Fission Yeast ◽  
Spindle Assembly Checkpoint ◽  
Spindle Assembly ◽  
Cell Division Cycle ◽  
Defective Mutant ◽  
A Cell

scholarly journals Saccharomyces cerevisiae Arc35p works through two genetically separable calmodulin functions to regulate the actin and tubulin cytoskeletons

2000 ◽  
Vol 113 (3) ◽  
pp. 521-532 ◽  
Author(s):  
C. Schaerer-Brodbeck ◽  
H. Riezman
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Cell Cycle ◽  
Cell Division ◽  
Actin Cytoskeleton ◽  
Spindle Assembly Checkpoint ◽  
Spindle Assembly ◽  
Restrictive Temperature ◽  
Metaphase Arrest ◽  
A Cell ◽  
Synthetically Lethal

Analysis of the arc35-1 mutant has revealed previously that this component of the Arp2/3 complex is involved in organization of the actin cytoskeleton. Further characterization uncovered a cell division cycle phenotype with arrest as large-budded cells. Cells with correctly positioned metaphase spindles accumulated at the restrictive temperature. The observed metaphase arrest most likely occurs by activation of the spindle assembly checkpoint, because arc35-1 was synthetically lethal with a deletion of BUB2. Arc35p activity is required late in G(1) for its cell cycle function. Both the actin and microtubule defects of arc35-1 can be suppressed by overexpression of calmodulin. Analysis of a collection of ts cmd1 mutants for their ability to suppress the actin and/or microtubule defect revealed that the two defects observed in arc35-1 are genetically separable. These data suggest that the actin defect is probably not the cause of the microtubule defect.

scholarly journals Mathematical model of the cell division cycle of fission yeast

2001 ◽  
Vol 11 (1) ◽  
pp. 277 ◽  
Author(s):  
Bela Novak ◽  
Zsuzsa Pataki ◽  
Andrea Ciliberto ◽  
John J. Tyson
Keyword(s):  
Mathematical Model ◽  
Cell Division ◽  
Fission Yeast ◽  
Cell Division Cycle

Spindle Assembly Checkpoint Protein Dynamics and Roles in Plant Cell Division

2011 ◽  
pp. 142-153
Author(s):  
Marie-Cécile Caillaud ◽  
Laetitia Paganelli ◽  
Philippe Lecomte ◽  
Laurent Deslandes ◽  
Michaël Quentin ◽  
...  
Keyword(s):  
Cell Division ◽  
Protein Dynamics ◽  
Plant Cell ◽  
Spindle Assembly Checkpoint ◽  
Spindle Assembly ◽  
Checkpoint Protein ◽  
Plant Cell Division ◽  
Spindle Assembly Checkpoint Protein

scholarly journals Disruption of Astral Microtubule Contact with the Cell Cortex Activates a Bub1, Bub3, and Mad3-dependent Checkpoint in Fission Yeast

2004 ◽  
Vol 15 (7) ◽  
pp. 3345-3356 ◽  
Author(s):  
Sylvie Tournier ◽  
Yannick Gachet ◽  
Vicky Buck ◽  
Jeremy S. Hyams ◽  
Jonathan B.A. Millar
Keyword(s):  
Actin Cytoskeleton ◽  
Fission Yeast ◽  
Spindle Assembly Checkpoint ◽  
Spindle Assembly ◽  
Yeast Cells ◽  
Cell Cortex ◽  
Checkpoint Proteins ◽  
Sister Chromatids ◽  
Astral Microtubule ◽  
Spindle Rotation

In animal and yeast cells, the mitotic spindle is aligned perpendicularly to the axis of cell division. This ensures that sister chromatids are separated to opposite sides of the cytokinetic actomyosin ring. In fission yeast, spindle rotation is dependent upon the interaction of astral microtubules with the cortical actin cytoskeleton. In this article, we show that addition of Latrunculin A, which prevents spindle rotation, delays the separation of sister chromatids and anaphase promoting complex-mediated destruction of spindle-associated Securin and Cyclin B. Moreover, we find that whereas sister kinetochore pairs normally congress to the spindle midzone before anaphase onset, this congression is disrupted when astral microtubule contact with the actin cytoskeleton is disturbed. By analyzing the timing of kinetochore separation, we find that this anaphase delay requires the Bub3, Mad3, and Bub1 but not the Mad1 or Mad2 spindle assembly checkpoint proteins. In agreement with this, we find that Bub1 remains associated with kinetochores when spindles are mispositioned. These data indicate that, in fission yeast, astral microtubule contact with the medial cell cortex is monitored by a subset of spindle assembly checkpoint proteins. We propose that this checkpoint ensures spindles are properly oriented before anaphase takes place.

scholarly journals Synergistic role of fission yeast Alp16GCP6 and Mzt1MOZART1 in γ-tubulin complex recruitment to mitotic spindle pole bodies and spindle assembly

2016 ◽  
Vol 27 (11) ◽  
pp. 1753-1763 ◽  
Author(s):  
Hirohisa Masuda ◽  
Takashi Toda
Keyword(s):  
Fission Yeast ◽  
Mitotic Spindle ◽  
Spindle Assembly Checkpoint ◽  
Synthetic Lethality ◽  
Spindle Assembly ◽  
Spindle Pole ◽  
Microtubule Assembly ◽  
Spindle Microtubule ◽  
Spindle Pole Bodies ◽  
Mitotic Spindle Pole

In fission yeast, γ-tubulin ring complex (γTuRC)–specific components Gfh1GCP4, Mod21GCP5, and Alp16GCP6 are nonessential for cell growth. Of these deletion mutants, only alp16Δ shows synthetic lethality with temperature-sensitive mutants of Mzt1MOZART1, a component of the γTuRC required for recruitment of the complex to microtubule-organizing centers. γ-Tubulin small complex levels at mitotic spindle pole bodies (SPBs, the centrosome equivalent in fungi) and microtubule levels for preanaphase spindles are significantly reduced in alp16Δ cells but not in gfh1Δ or mod21Δ cells. Furthermore, alp16Δ cells often form monopolar spindles and frequently lose a minichromosome when the spindle assembly checkpoint is inactivated. Alp16GCP6 promotes Mzt1-dependent γTuRC recruitment to mitotic SPBs and enhances spindle microtubule assembly in a manner dependent on its expression levels. Gfh1GCP4 and Mod21GCP5 are not required for Alp16GCP6-dependent γTuRC recruitment. Mzt1 has an additional role in the activation of the γTuRC for spindle microtubule assembly. The ratio of Mzt1 to γTuRC levels for preanaphase spindles is higher than at other stages of the cell cycle. Mzt1 overproduction enhances spindle microtubule assembly without affecting γTuRC levels at mitotic SPBs. We propose that Alp16GCP6 and Mzt1 act synergistically for efficient bipolar spindle assembly to ensure faithful chromosome segregation.

Sign in / Sign up

Export Citation Format

Share Document