Cooperative Assembly of CYK-4/MgcRacGAP and ZEN-4/MKLP1 to Form the Centralspindlin Complex

Pavicic-Kaltenbrunner, Visnja; Mishima, Masanori; Glotzer, Michael

doi:10.1091/mbc.e07-05-0468

Cited by 108 publications

(104 citation statements)

References 35 publications

Supporting

Mentioning

101

Contrasting

Order By: Relevance

“…ZEN-4 m derivatives containing single cysteine residues were assayed for disulfide bridge formation under oxidizing conditions followed by nonreducing gel electrophoresis to measure dimer formation in the presence and absence of CYK-4 m . As a positive control, we assayed the cross-linking efficiency of cysteine 547, which is predicted to lie in the internal region of the parallel coiled coil region in ZEN-4 (position a or d) (14). As seen previously with ZEN-4(1-555), a cysteine at this position allows efficient formation of cross-linked dimers, both in the presence and absence of CYK-4 m (Fig.…”

Section: Biochemical Characterization Of Centralspindlinmentioning

confidence: 75%

“…In the bound state, these sites exhibit the smallest intradimer distances of all the sites we measured. In light of this correlation, we speculate that CYK- tion (2,14), due to the identification of single ZEN-4 mutations that rescue mutations in both CYK-4 and ZEN-4.…”

mentioning

confidence: 88%

“…The central spindle can also dictate the site of cleavage furrow formation (4 -9) and is required for proper completion of cytokinesis (10 -13). Intriguingly, bundling of microtubules in vitro requires the presence of both ZEN-4/MKLP1 and CYK-4/ MgcRacGAP and their ability to bind with high affinity (14). Similarly, the centralspindlin complex, but not the individual subunits alone, can support microtubule bundling and central spindle assembly in vivo (11)(12)(13).…”

mentioning

confidence: 99%

“…1, A and B). The coiled coils of CYK-4 and ZEN-4 contribute to the high affinity interaction, although they do not interact directly as they can be substituted by alternate parallel coiled coils (14).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Binding of the CYK-4 Subunit of the Centralspindlin Complex Induces a Large Scale Conformational Change in the Kinesin Subunit

White

Raghuraman

Perozo

et al. 2013

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Background: Cytokinesis requires formation of the centralspindlin complex. Results: The neck linker regions in ZEN-4 are highly mobile when free, but their mobility is greatly restricted by CYK-4 binding. Conclusion: Central spindle assembly requires a binding event that modulates the structure of the kinesin ZEN-4. Significance: Structural changes in the centralspindlin complex contribute to cell division.

show abstract

Section: Biochemical Characterization Of Centralspindlinmentioning

confidence: 75%

mentioning

confidence: 88%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Binding of the CYK-4 Subunit of the Centralspindlin Complex Induces a Large Scale Conformational Change in the Kinesin Subunit

White

Raghuraman

Perozo

et al. 2013

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…The role of the Centralspindlin proteins in mitotic spindle midzone formation and stabilization leading to cytokinesis is well documented (Guse et al 2005;D'Avino et al 2006;Pavicic-Kaltenbrunner et al 2007;Simon et al 2008). Their contribution to acentrosomal spindle assembly, however, has not been characterized.…”

Section: Antibodies and Immunofluorescent Microscopymentioning

confidence: 99%

Spindle Assembly and Chromosome Segregation Requires Central Spindle Proteins inDrosophilaOocytes

et al. 2015

View full text Add to dashboard Cite

Oocytes segregate chromosomes in the absence of centrosomes. In this situation, the chromosomes direct spindle assembly. It is still unclear in this system which factors are required for homologous chromosome bi-orientation and spindle assembly. The Drosophila kinesin-6 protein Subito, although nonessential for mitotic spindle assembly, is required to organize a bipolar meiotic spindle and chromosome bi-orientation in oocytes. Along with the chromosomal passenger complex (CPC), Subito is an important part of the metaphase I central spindle. In this study we have conducted genetic screens to identify genes that interact with subito or the CPC component Incenp. In addition, the meiotic mutant phenotype for some of the genes identified in these screens were characterized. We show, in part through the use of a heat-shock-inducible system, that the Centralspindlin component RacGAP50C and downstream regulators of cytokinesis Rho1, Sticky, and RhoGEF2 are required for homologous chromosome bi-orientation in metaphase I oocytes. This suggests a novel function for proteins normally involved in mitotic cell division in the regulation of microtubulechromosome interactions. We also show that the kinetochore protein, Polo kinase, is required for maintaining chromosome alignment and spindle organization in metaphase I oocytes. In combination our results support a model where the meiotic central spindle and associated proteins are essential for acentrosomal chromosome segregation. KEYWORDS meiosis; synthetic lethal mutation; homolog bi-orientation; spindle; chromosome segregation; Drosophila C HROMOSOMES are segregated during cell division by the spindle, a bipolar array of microtubules. In somatic cells, spindle assembly is guided by the presence of centrosomes at the poles. In this conventional spindle assembly model, the kinetochores attach to microtubules from opposing centrosomes and tension is established. This satisfies the spindle assembly checkpoint, which then allows the cell to proceed to anaphase (Musacchio and Salmon 2007). Cell division is completed by recruiting proteins to a midzone of antiparallel microtubules that forms between the segregated chromosomes, signaling furrow formation (Fededa and Gerlich 2012;D'Avino et al. 2015). However, spindle morphogenesis in oocytes of many animals occurs in the absence of centrosomes. This may contribute to the high rates of segregation errors that are maternal in origin and are a leading cause of miscarriages, birth defects, and infertility (Herbert et al. 2015). How a robust spindle assembles without guidance from the centrosomes is not well understood. While it is clear that the chromosomes can recruit microtubules and drive spindle assembly (Tseng et al. 2010;Dumont and Desai 2012), how a bipolar spindle is organized and chromosomes make the correct attachments to microtubules is not understood.The Drosophila oocyte provides a genetically tractable system for the identification of genes involved in acentrosomal spindle assembly. Substantial evidence in Drosop...

show abstract

Human Endonuclease ANKLE1 Localizes at the Midbody and Processes Chromatin Bridges to Prevent DNA Damage and cGAS‐STING Activation

et al. 2023

View full text Add to dashboard Cite

Chromatin bridges connecting the two segregating daughter nuclei arise from chromosome fusion or unresolved interchromosomal linkage. Persistent chromatin bridges are trapped in the cleavage plane, triggering cytokinesis delay. The trapped bridges occasionally break during cytokinesis, inducing DNA damage and chromosomal rearrangements. Recently, Caenorhabditis elegans LEM‐3 and human TREX1 nucleases have been shown to process chromatin bridges. Here, it is shown that ANKLE1 endonuclease, the human ortholog of LEM‐3, accumulates at the bulge‐like structure of the midbody via its N‐terminal ankyrin repeats. Importantly, ANKLE1−/− knockout cells display an elevated level of G1‐specific 53BP1 nuclear bodies, prolonged activation of the DNA damage response, and replication stress. Increased DNA damage observed in ANKLE1−/− cells is rescued by inhibiting actin polymerization or reducing actomyosin contractility. ANKLE1 does not act in conjunction with structure‐selective endonucleases, GEN1 and MUS81 in resolving recombination intermediates. Instead, ANKLE1 acts on chromatin bridges by priming TREX1 nucleolytic activity and cleaving bridge DNA to prevent the formation of micronuclei and cytosolic dsDNA that activate the cGAS‐STING pathway. It is therefore proposed that ANKLE1 prevents DNA damage and autoimmunity by cleaving chromatin bridges to avoid catastrophic breakage mediated by actomyosin contractile forces.

show abstract

Cooperative Assembly of CYK-4/MgcRacGAP and ZEN-4/MKLP1 to Form the Centralspindlin Complex

Cited by 108 publications

References 35 publications

Binding of the CYK-4 Subunit of the Centralspindlin Complex Induces a Large Scale Conformational Change in the Kinesin Subunit

Binding of the CYK-4 Subunit of the Centralspindlin Complex Induces a Large Scale Conformational Change in the Kinesin Subunit

Spindle Assembly and Chromosome Segregation Requires Central Spindle Proteins inDrosophilaOocytes

Human Endonuclease ANKLE1 Localizes at the Midbody and Processes Chromatin Bridges to Prevent DNA Damage and cGAS‐STING Activation

Contact Info

Product

Resources

About