• This protein may have a role in efficient chromosome congression and segregation by promoting microtubule-dependent microtubule amplification. (nih.gov)
  • In the mammalian genome, this group of proteins assembles at tens of thousands of sites all at once, ensuring each chromosome is copied precisely once per cell division. (cshl.edu)
  • The Stillman lab searched for the protein(s) that start cell chromosome duplication, rather than virus genome replication. (cshl.edu)
  • Namely, the mitosis in the absence of centrosomes took much longer, and was prone to errors, which led to a prominent increase of chromosome abnormalities (aneuploidy). (databasefootball.com)
  • Conversely, we identify a novel role for two microtubule-growth and nucleation agents, Ran and CLASP, in the establishment of the centrosome-independent force during anaphase.Their involvement raises the interesting possibility that microtubule polymerization of midzone microtubules is continuously required to sustain chromosome segregation during mitosis. (ens-lyon.fr)
  • 3.0: hematopoietic cell-specific Lyn substrate 1 (HCLS1), Kelch domain-containing 6 (KLHDC6), sarcoglycan delta (SGCD), KIAA1706 protein (KIAA1706), RNA guanylyltransferase and 5′-phosphatase (RNGTT), chromosome 10 open reading frame 57 (C10orf57), chromosome 9 open reading frame 52 (C9orf52), and plasminogen activator, urokinase receptor (PLAUR). (molvis.org)
  • In humans, the CRYAA gene encodes a 173 amino acid residue protein by single copy genes located on chromosome 21. (molvis.org)
  • reveal that a scaffold formed by the proteins centrosomin and PLP is required to maintain the activity of interphase centrosomes, which is essential for nuclear spacing and proper chromosome segregation. (scivee.tv)
  • 1998). At the onset of mitosis, when centrosomes separate to form the bipolar spindle, C-Nap1 dissociates (Mayor et al. (reactome.org)
  • The experiments revealed that p53 was activated due to the prolonged mitosis following centrosome loss, but the molecular identity of putative stress signal leading to its upregulation was not deciphered yet. (databasefootball.com)
  • Chromatids segregate without centrosomes during Caenorhabditis elegans mitosis in a Ran- and CLASP-dependent manner. (ens-lyon.fr)
  • Home / Teams / Evolutionary Cell Biology in Nematodes - M. Delattre / Publications / Chromatids segregate without centrosomes during Caenorhabditis elegans mitosis in a Ran- and CLASP-dependent manner. (ens-lyon.fr)
  • Using laser destruction of the centrosomes during Caenorhabditis elegans mitosis, we show that neither of these mechanisms is necessary to achieve proper chromatid segregation. (ens-lyon.fr)
  • controls the timing of entry into mitosis/meiosis by controlling the subsequent activation of cyclin B/CDK1 by phosphorylation, and coordinates the activation of cyclin B/CDK1 at the centrosome and in the nucleus. (proteopedia.org)
  • Consistent with this change in direction, Hyman (now at the Max Planck Institute of Molecular Cell Biology in Dresden, Germany) found that in AB cells the newly duplicated centrosomes migrated to opposite sides of the nucleus before mitosis. (rupress.org)
  • However, mechanistic details are lacking, and recent studies have implicated ALMS1 in several processes including endosomal trafficking, actin organisation, maintenance of centrosome cohesion and transcription. (springer.com)
  • The centrosomal protein C-Nap1 is thought to play an important role in centrosome cohesion during interphase (Fry et al. (reactome.org)
  • Centrosomes consist of a centriole pair surrounded by a protein network known as pericentriolar material (PCM)1. (harvard.edu)
  • The core of the centrosome is made by a pair of centrioles, barrel-shape structures embedded in a matrix of proteins termed the pericentriolar material. (databasefootball.com)
  • Alternatively, force could be generated along the length or tip of MTs by motor proteins and may be transmitted to the CS. (europa.eu)
  • The similarity of carbon nanotube s to microtubules suggests a potential to interact with cellular biomolecules, such as the mitotic spindle, as well as the motor proteins that separate the chromosomes during cell division. (cdc.gov)
  • ALMS1 encodes a ~ 0.5 megadalton protein that localises to the base of centrioles. (springer.com)
  • Centrosome duplicates once per cell cycle, with proteins PLK4 and STIL playing the pivotal role in the regulation of a key step in centrosome cycle - the duplication of centrioles. (databasefootball.com)
  • Even though centrosome and centrioles have already been studied for over a century, it is only the recent years when centrosome-focused research has boomed and flourished, as many previously unpredicted links to human diseases, embryogenesis, and development have been revealed. (databasefootball.com)
  • The Centrosome (CS) is an organelle located near the nucleus that constitutes the primary Microtubule Organization Center (MTOC) in animal cells. (europa.eu)
  • The nucleus houses the cell's DNA and directs the synthesis of proteins and ribosomes. (coursehero.com)
  • Therefore, the nucleus houses the cell's DNA and directs the synthesis of proteins and ribosomes, the cellular organelles responsible for protein synthesis. (coursehero.com)
  • The nucleus stores chromatin (DNA plus proteins) in a gel-like substance called the nucleoplasm.The nucleolus is a condensed region of chromatin where ribosome synthesis occurs.The boundary of the nucleus is called the nuclear envelope.It consists of two phospholipid bilayers: an outer membrane and an inner membrane.The nuclear membrane is continuous with the endoplasmic reticulum.Nuclear pores allow substances to enter and exit the nucleus. (coursehero.com)
  • The ORC complex proteins are kept near each other in liquid compartments in the nucleus and recruit proteins such as CDC6 and other proteins that control when to commit the cell to divide. (cshl.edu)
  • The same migration of duplicated centrosomes occurred in P 1 cells, but then the nucleus rotated 90 degrees, dragging the centrosomes with it. (rupress.org)
  • Immunofluorescence revealed nets of microtubules stretching from the centrosomes to the cell cortex, suggesting that these fibers helped position the structures and turn the nucleus. (rupress.org)
  • Hyman concluded that one spot on the anterior cortex was hooking the centrosome's microtubules and reeling in the centrosome, thereby turning the nucleus. (rupress.org)
  • What exerts the force on the nucleus and centrosomes remains uncertain. (rupress.org)
  • In toto , our results show that the connection between centrosomes and chromosomes is mediated by an anchoring into the entire spindle network and that any direct connections through KMTs are few and likely very transient. (nature.com)
  • If the role of KMTs is to mediate forces between chromosomes and spindle poles, they need to somehow connect to the centrosomes. (nature.com)
  • Proteins called microtubules assemble into a spindle between the two centrosomes and help separate the replicated chromosomes into the daughter cells. (genome.gov)
  • Not only are ORC proteins involved in DNA replication, but they also help divide the chromosomes equally into the two new cells. (cshl.edu)
  • Our results strongly suggest that an outward forcegenerated by the spindle midzone, independently of centrosomes, is sufficient tosegregate chromosomes in mitotic cells. (ens-lyon.fr)
  • Disruption of centrosomes and mitotic spindles would result in monopolar, tripolar, and quadrapolar divisions of chromosomes. (cdc.gov)
  • Some studies have suggested a role for this protein in maintaining centriole-nucleated sensory organelles termed primary cilia, and AS is now considered to belong to the growing class of human genetic disorders linked to ciliary dysfunction (ciliopathies). (springer.com)
  • We demonstrate that a Drosophila Golgi protein, Gorab, is present not only in the trans-Golgi but also in the centriole cartwheel where, complexed to Sas6, it is required for centriole duplication. (uni-koeln.de)
  • Our findings suggest that during animal evolution, a Golgi protein has arisen with a second, apparently independent, role in centriole duplication. (uni-koeln.de)
  • Description: A competitive ELISA for quantitative measurement of Human Anti centriole and centrosome antibody IgG in samples from blood, plasma, serum, cell culture supernatant and other biological fluids. (microarraystation.com)
  • Displacement of DVL from the centrosome and its release into the cytoplasm on NEK2 phosphorylation is coupled to the removal of linker proteins, an event necessary for centrosomal separation and proper formation of the mitotic spindle. (muni.cz)
  • 2000). Dissociation of C-Nap1 from mitotic centrosomes appears to be regulated by phosphorylation (Mayor et al. (reactome.org)
  • NPM1 phosphorylation by cyclin E/CDK2 promotes its dissociates from unduplicated centrosomes, thus initiating centrosome duplication. (proteopedia.org)
  • This gene encodes a protein containing a large tandem-repeat domain as well as additional low complexity regions. (wikipedia.org)
  • This gene encodes a centrosome and spindle pole associated protein. (nih.gov)
  • This protein is a catalytic kinesin motor with coiled-coil and Smc domains. (biolegend.com)
  • The aggresome is juxtanuclear inclusion body containing heat-shock proteins and components of the ubiquitin-proteasome system ( Olzmann et al, 2008 ). (biorxiv.org)
  • The juxtanuclear location of the aggresome is shared by the centrosome, the microtubule organising centre of the cell. (biorxiv.org)
  • Most of these mutations lead to the production of an abnormally small version of the ALMS1 protein that does not function properly. (medlineplus.gov)
  • Mutations in the genes that encode these proteins can result in disease. (cshl.edu)
  • Scope includes mutations and abnormal protein expression. (cancerindex.org)
  • ADPKD is due to mutations in the genes PKD1 and PKD2, which encode polycystin proteins. (medscape.com)
  • The encoded protein functions in microtubule organization, particularly in the formation and maintenance of cilia. (wikipedia.org)
  • Unexpectedly, CN shows SLiM-dependent proximity to centrosomal and nuclear pore complex (NPC) proteins-structures where Ca 2+ signaling is largely uncharacterized. (nih.gov)
  • This creates interfaces for efficient binding to CDK5 regulatory subunit-associated protein 2 (CDK5RAP2) and centrosomal Nek2-associated protein 1 (C-NAP1), two proteins of the centrosomal linker. (muni.cz)
  • In line with a more complex picture, multiple isoforms of the protein likely exist and non-centrosomal sites of localisation have been reported. (springer.com)
  • The encoded protein plays a role in cell-cycle progression and spindle organization, regulates cytokinesis, interacts with Nephrocystin 8 and is required for cilia formation. (nih.gov)
  • They develop in a juxtanuclear position, adjacent to the centrosome, the microtubule organizing centre of the cell, and share some protein components. (biorxiv.org)
  • Despite the long-standing observation that aggresomes/Lewy bodies and the centrosome sit side-by-side in the cell, no studies have been done to see whether these protein accumulations impede the organelle function. (biorxiv.org)
  • Since dopaminergic neurons are polarised, ensuring correct localisation of organelles and the effective intracellular transport of neurotransmitter vesicles, loss of centrosome activity could contribute to loss of dopaminergic function and neuronal cell death in Parkinson's disease. (biorxiv.org)
  • Centrosomes play a role in cell division and the assembly of microtubules, which are proteins that transport materials in cells and help the cell maintain its shape. (medlineplus.gov)
  • Recent breakthroughs have uncovered more and more DNA replication licensing machinery proteins (ORC, Cdc6, Cdt1, geminin, etc.) functioning in other cell cycle events, including centrosome replication, mitotic events, transcription and so on. (intechopen.com)
  • The precise regulations of pre-RC protein levels and assembly are effective ways to prevent reassembly of de novo MCM2-7 onto the replicated origins to re-license and re-replicate the genomic DNA in the subsequent phases of the same cell cycle ( Figure 1) . (intechopen.com)
  • A centrosome is a cellular structure involved in the process of cell division. (genome.gov)
  • Before cell division, the centrosome duplicates and then, as division begins, the two centrosomes move to opposite ends of the cell. (genome.gov)
  • The centrosome is an important part of how the cell organizes the cell division. (genome.gov)
  • The centrosomes duplicate before cell division, so they then help to organize the microtubules and the cell division process. (genome.gov)
  • The origin recognition complex (ORC) is a group of proteins involved with every cell division event in our cells. (cshl.edu)
  • The SV40 T-antigen, the first protein the virus makes inside a host cell, is needed for the very first step of replication of the virus DNA. (cshl.edu)
  • T-antigen hijacks other proteins from the infected cell to replicate the virus genome. (cshl.edu)
  • Over the next few decades researchers would use SV40 replication to discover dozens of cellular proteins that are necessary for human cell genome replication. (cshl.edu)
  • Binding of this protein to CXCR3 results in pleiotropic effects, including stimulation of monocytes, natural killer and T-cell migration, and modulation of adhesion molecule expression. (cancerindex.org)
  • Total cell lysates (15 µg total protein) from A431, SH-SY5Y, MCF-7 (reduced expression control), and NIH3T3 cells were resolved by 4-12% Bis-Tris gel electrophoresis, transferred to a nitrocellulose membrane, and probed with 0.5 µg/mL (1:1000 dilution) Purified anti-EG5 Antibody, clone 10C7, overnight at 4°C. Proteins were visualized by chemiluminescence detection using HRP goat anti-mouse IgG Antibody (Cat. (biolegend.com)
  • The AAA-ATPase (ATPases associated with diverse cellular activities) valosin-containing protein (VCP), is essential for many cellular pathways including but not limited to endoplasmic reticulum-associated degradation (ERAD), DNA damage responses, and cell cycle regulation. (portlandpress.com)
  • Combining spatial and abundance information yielded an unprecedented quantitative view of HeLa cell anatomy and organellar composition, at the protein level. (elifesciences.org)
  • Dynamic Organellar Maps enable the proteome-wide analysis of physiological protein movements, without requiring any reagents specific to the investigated process, and will thus be widely applicable in cell biology. (elifesciences.org)
  • Proteins are the tools and machines of the cell, and each organelle has its own set of proteins that it requires to work correctly. (elifesciences.org)
  • Each cell contains ten or more organelles, and several thousand different types of proteins. (elifesciences.org)
  • The location of many proteins in a cell is unclear or simply not known. (elifesciences.org)
  • set out to develop a method that reveals the locations of all the proteins in a cell at any given time. (elifesciences.org)
  • The resulting technique maps the location of most of the proteins in a human cancer cell line and, in addition, determines how many copies of each protein there are. (elifesciences.org)
  • Centrosome is an organelle responsible for the organization of microtubule arrays, typically implicated in the organization of cell division, cell motility, and cell shape. (databasefootball.com)
  • As the cell divides, each daughter cell inherits precisely one centrosome. (databasefootball.com)
  • Curiously, despite numerous studies with these cells, the importance and function of centrosome in this cell type has remained elusive. (databasefootball.com)
  • Firstly, analysis of cell divisions confirmed that stem cells are able to arrange mitotic spindle and to divide even without any centrosome, with no major impact on survival of these cells, which was not anticipated. (databasefootball.com)
  • The team subsequently focused on the examination of effects of centrosome depletion on stem cell properties to find that the centrosome loss led to downregulation of regulators of pluripotency OCT-4 and NANOG and a concomitant increase in the expression of proteins which marked the initiation of differentiation program (namely p53, PAX-6, brachyury etc. (databasefootball.com)
  • Given that p53 has been shown to mediate consequences of centrosome loss in mice and human somatic cell lines, the team examined its role in the context of centrosome loss in human stem cells. (databasefootball.com)
  • Functional annotation clustering showed that they belong to cell cycle, organelle or nuclear lumen, protein transport, and DNA binding and repair clusters. (molvis.org)
  • Cyclin-dependent kinases (CDKs) are serine/threonine protein kinases that act as key regulatory elements in cell cycle progression. (proteopedia.org)
  • (A) Western blot analysis of cell lysates obtained from RPEp53 −/− , RPEp53 −/− SAS6 −/− , and RPEp53 −/− STIL −/− cells (loaded with equal amounts of total protein) using SAS6, STIL, γ-tubulin, and β-actin antibodies. (life-science-alliance.org)
  • The absence of the centrosome changes global microtubule dynamics in a migrating cell. (life-science-alliance.org)
  • Centrosomes undergo dramatic changes in size and structure during the rapid cell cycles of early Drosophila embryos. (scivee.tv)
  • Recent work suggests that centrosome movements are linked to another intracellular migration: the spindle's shift toward the posterior end of the cell during anaphase, which sets up an unequal division. (rupress.org)
  • Introduction: Proteasome inhibition is first line therapy in multiple myeloma (MM). The immunological potential of cell death triggered by defects of the ubiquitin-proteasome system (UPS) and subsequent perturbations of protein homeostasis is, however, less well defined. (bvsalud.org)
  • Methods: In this paper, we applied the protein homeostasis disruptors bortezomib (BTZ), ONX0914, RA190 and PR619 to various MM cell lines and primary patient samples to investigate their ability to induce immunogenic cell death (ICD). (bvsalud.org)
  • The microtubule-associated protein EML3 regulates mitotic spindle assembly by recruiting the Augmin complex to spindle microtubules. (nih.gov)
  • ALMS1, centrosome and basal body associated protein is a protein that in humans is encoded by the ALMS1 gene. (wikipedia.org)
  • The ALMS1 gene provides instructions for making a protein whose function is unknown. (medlineplus.gov)
  • The protein encoded by this gene is a subunit of the augmin complex. (nih.gov)
  • What does this gene/protein do? (cancerindex.org)
  • What pathways are this gene/protein implicaed in? (cancerindex.org)
  • Interestingly, inhibition of protein de-ubiquitination by PR619 was associated with the acquisition of a strong type I IFN gene signature which relied on key components of the unfolded protein and integrated stress responses including inositol-requiring enzyme 1 (IRE1), protein kinase R (PKR) and general control nonderepressible 2 (GCN2). (bvsalud.org)
  • The human ORC is composed of ORC1, ORC2, ORC3, ORC4, ORC5, and ORC6 and binds to a protein called CDC6 that is related to ORC1. (cshl.edu)
  • When the ORC1 protein binds to DNA, it recruits CDC6, a protein that regulates and recruits other proteins, to a liquid phase and completes the ORC ring. (cshl.edu)
  • in eukaryotic cells the most important of these proteins are the histones . (wikipedia.org)
  • The crystal structure of Caenorhabditis elegans F53F4.3 protein Q20728 CAP-Gly domain was recently solved ( PUBMED:12221106 ). (embl.de)
  • The crystal structure of the Caenorhabditis elegans F53F4.3 protein CAP-Gly domain has been solved. (embl.de)
  • The crystal structure ofthe CAP-Gly domain of Caenorhabditis elegans F53F4.3 protein, solved bysingle wavelength sulfur-anomalous phasing, revealed a novel protein foldcontaining three beta-sheets. (embl.de)
  • As a graduate student at the MRC Laboratory of Molecular Biology in Cambridge, England, Anthony Hyman showed how the centrosomes' travels set up the division axis in Caenorhabditis elegans ( Hyman and White, 1987 ). (rupress.org)
  • Aggresomes are closely-related cellular accumulations of misfolded proteins. (biorxiv.org)
  • The ALMS1 protein is present in most of the body's tissues, usually at low levels. (medlineplus.gov)
  • The ALMS1 protein is also found at the base of cilia, which are finger-like projections that stick out from the surface of cells. (medlineplus.gov)
  • Based on its location within cells, researchers suggest that the ALMS1 protein might be involved in the organization of microtubules, the transport of various materials, and the normal function of cilia. (medlineplus.gov)
  • Researchers propose that a lack of normally functioning ALMS1 protein in the brain could lead to overeating. (medlineplus.gov)
  • The helical, highly charged DMIF1 protein monomer contains an N-terminal targeting domain to transfer the precursor, synthesized in the cytoplasm, to mitochondria. (tum.de)
  • The relationship between lysate protein concentration from paclitaxel-treated and hydroxyurea-treated HeLa cells and the absorbance at 450 nm using the PathScan ® RP Phospho-Aurora A (Thr288) Sandwich ELISA Kit #41333 is shown in the upper figure. (cellsignal.com)
  • We initially used maps statically to generate a database with localization and absolute copy number information for over 8700 proteins from HeLa cells, approaching comprehensive coverage. (elifesciences.org)
  • CN dephosphorylates human and yeast NPC proteins and promotes accumulation of a nuclear transport reporter, suggesting conserved NPC regulation by CN. (nih.gov)
  • Eg5 (also known as kinesin-like protein KIF11, kinesin-related motor protein Eg5, kinesin-like spindle protein HKSP, and thyroid receptor interacting protein 5 (TRIP5)) is a 119 kD kinesin-like protein family, BimC subfamily. (biolegend.com)
  • We have developed and applied Dynamic Organellar Maps, a proteomic method that allows global mapping of protein translocation events. (elifesciences.org)
  • The effect of miR-34/449 on ciliogenesis was mediated, at least in part, by post-transcriptional repression of Cp110, a centriolar protein suppressing cilia assembly. (nature.com)
  • In the study Inactivation of PLK4-STIL Module Prevents Self-Renewal and Triggers p53-Dependent Differentiation in Human Pluripotent Stem Cells, Renzova and colleagues blocked the function of PLK4 or STIL with the idea to put a brake on the centrosome duplication pathway and hence to prevent centrosome to duplicate in stem cells. (databasefootball.com)
  • The study revealed that applying this strategy led to a complete depletion of centrosome in over 85% of stem cells after 3 days of blocking the duplication pathway. (databasefootball.com)
  • We investigated whether the formation of aggresomes affected key centrosome functions: its ability to organize the microtubule network and to promote cilia formation. (biorxiv.org)
  • Sterical blocking of the targeting domain by the reporter protein GFP fused to DMIF1 N-terminus targets the protein to aggresomes in the pericentrosomal region, where the unfolded protein is degradated. (tum.de)
  • We then showed that Tubulin, the building block of microtubules, functions as a switch like regulatory subunit that regulates the formation of the PCM complexes, and centrosome function. (utoledo.edu)
  • This motor protein is required for establishing the bipolar spindle. (biolegend.com)
  • By combining centrosome biochemistry with Drosophila genetics, we have found that Sas-4 forms several complexes of PCM proteins. (utoledo.edu)
  • This revealed which proteins had changed location, identifying these proteins as important for the cell's response to the growth factor. (elifesciences.org)
  • Hyman tackled this issue in a follow-up study, using a laser to slice the microtubules between either of the centrosomes and the cell's anterior cortex ( Hyman, 1989 ). (rupress.org)
  • In normal cells, the centrosomes are equally likely to turn toward the cell's anterior. (rupress.org)
  • The human ORC consists of six proteins when fully assembled into a ring around a stretch of DNA . (cshl.edu)
  • Predicted expression data was obtained from Human Protein Atlas. (biolegend.com)
  • Cdc42 protein: GST tagged: human dominant negative (Cat. (cytoskeleton.com)
  • Cdc42 protein: His tagged: human constitutively active (Cat. (cytoskeleton.com)
  • Cdc42 protein: His tagged: human wild type (Cat. (cytoskeleton.com)
  • In fact, these findings raised an alerting question if centrosome might perhaps be a completely obsolete organelle for human stem cells. (databasefootball.com)
  • To identify proteins interacting with alpha A-crystallin (CRYAA) and to investigate the potential role that these protein interactions play in the function of CRYAA using a human proteome (HuProt) microarray. (molvis.org)
  • A HuProt microarray composed of 17,225 human full-length proteins with N-terminal glutathione S-transferase (GST) tags was used to identify protein-protein interactions. (molvis.org)
  • One-hundred and twenty-seven of 17,225 human full-length proteins were identified that interact with CRYAA. (molvis.org)
  • VCP primarily identifies ubiquitylated proteins in these pathways and mediates their unfolding and degradation by the 26S proteasome. (portlandpress.com)
  • Subcellular localization critically influences protein function, and cells control protein localization to regulate biological processes. (elifesciences.org)
  • Protein function is critically determined by subcellular localization, as organelles offer different chemical environments and interaction partners. (elifesciences.org)
  • In order to regulate protein activity, many biological processes involve changes in protein subcellular localization. (elifesciences.org)
  • VCP interacts with adaptor proteins to identify ubiquitylated substrates for degradation by the proteasome. (portlandpress.com)
  • The endoplasmic reticulum modifies proteins and synthesizes lipids, while the golgi apparatus is where the sorting, tagging, packaging, and distribution of lipids and proteins takes place. (coursehero.com)
  • and vertebrates ( Du and Macara, 2004 ), and one G protein component also controls centrosome rotation ( Gotta and Ahringer, 2001 ). (rupress.org)
  • total) from RPEp53 −/− , RPEp53 −/− SAS6 −/− , and RPEp53 −/− STIL −/− cells (loaded with equal amount of total protein) are shown. (life-science-alliance.org)
  • VCP identifies ubiquitylated substrates through numerous dedicated adaptor proteins and unfolds substrates by threading them through a central pore in the hexamer ( Figure 1 ). (portlandpress.com)
  • The rapid protocol (RP) PathScan ® RP Phospho-Aurora A (Thr288) Sandwich ELISA Kit is a solid phase sandwich enzyme-linked immunosorbent assay (ELISA) that detects endogenous levels of Aurora A protein phosphorylated at Thr288 in a reduced assay time of 1.5 hours. (cellsignal.com)
  • Everyone assumed that the centrosomes determined the positions of the spindle poles, but nobody knew how. (rupress.org)