Microtubule polymerization spindle apparatus. Medical search. Frequent questions

bipolar attachment of sister kinetochores to microtubules emanating from opposite cell poles couples opposing tension forces, aligning chromosomes at the cell equator and poising them for segregation to daughter cells. (wikipedia.org)
The cellular spindle apparatus includes the spindle microtubules, associated proteins, which include kinesin and dynein molecular motors, condensed chromosomes, and any centrosomes or asters that may be present at the spindle poles depending on the cell type. (wikipedia.org)
At the pointed ends, known as spindle poles, microtubules are nucleated by the centrosomes in most animal cells. (wikipedia.org)
Acentrosomal or anastral spindles lack centrosomes or asters at the spindle poles, respectively, and occur for example during female meiosis in most animals. (wikipedia.org)
Microtubule-associated proteins (MAPs) associate with microtubules at the midzone and the spindle poles to regulate their dynamics. (wikipedia.org)
The most efficient cytotoxic activity of the phenanthridine PJ34, caused significantly smaller aberrant spindles with disrupted spindle poles and scattered extra-centrosomes and chromosomes. (oncotarget.com)
The fully formed metaphase arrested Xenos oocyte meiotic apparatus contained an abundance of membranes and had diffuse poles that lacked distinct polar MT organizing centers. (silverchair.com)
Here, we show that, unlike mitotic cells, oocytes can repair DSBs during meiosis I through microtubule-dependent chromosomal recruitment of the CIP2A-MDC1-TOPBP1 complex from spindle poles. (bvsalud.org)
After DSB induction, we observed spindle shrinkage and stabilization, as well as BRCA1 and 53BP1 recruitment to chromosomes and subsequent DSB repair during meiosis I. Moreover, p-MDC1 and p-TOPBP1 were recruited from spindle poles to chromosomes in a CIP2A-dependent manner. (bvsalud.org)
Remarkably, despite the high turnover of microtubules throughout mitosis 2 , the spindle maintains its bipolar structure with the chromosomes at its center and two poles that are separated by the plane of cell division. (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)
The spindle apparatus is formed from very thin protein threads called microtubules that stretch between opposite poles of the cell during mitosis. (piltdownsuperman.com)

γ-tubulin is a specialized tubulin variant that assembles into a ring complex called γ-TuRC which nucleates polymerization of α/β tubulin heterodimers into microtubules. (wikipedia.org)
That SP600125 induces endoreduplication signals, promotes tubulin polymerization, a critical process in cell division, and induces delayed apoptosis in leukemia Aurora kinases cells. (hsp90-inhibitors.com)
Therefore, SP600125 has a strong anticancer effect against leukemia cells in a dose and time dependent manner by promoting tubulin polymerization and disrupting the organization of the microtubule cytoskeleton. (hsp90-inhibitors.com)
Using biochemical and immunofluorescence methods, we have shown that SP60015 significantly increases tubulin polymerization. (hsp90-inhibitors.com)
Our results strongly support the idea that SP600125 inhibits cell proliferation by inhibiting mitosis through extended tubulin polymerization. (hsp90-inhibitors.com)
Their activity prevented the binding of NuMA to α-tubulin and kinesins in human cancer cells, and caused aberrant spindles. (oncotarget.com)
Here, we characterize the Eg5 microtubule polymerase mechanism by assessing motor-induced changes in the longitudinal and lateral tubulin-tubulin bonds that form the microtubule lattice. (elsevierpure.com)
Eg5 binds preferentially to microtubules over free tubulin, which contrasts with microtubule-depolymerizing kinesins that preferentially bind free tubulin over microtubules. (elsevierpure.com)
Thus, we propose a microtubule polymerase mechanism in which Eg5 at the plus-end promotes a curved-to-straight transition in tubulin that enhances lateral bond formation and thereby promotes microtubule growth and stability. (elsevierpure.com)
propose a model in which Eg5 binding to tubulin promotes a curved-to-straight transition that drives microtubule assembly. (elsevierpure.com)
Microtubules are formed from protein subunits called tubulin . (pediagenosis.com)
Each microtubule consists of parallel protofilaments, each composed of α- and β-tubulin dimers. (pediagenosis.com)
The plant alkaloid colchicine binds to tubulin molecules and prevents the assembly of microtubules. (pediagenosis.com)
taxotere retains the unique mechanism of action of taxol and inhibits the depolymerisation of microtubules into tubulin. (liverpool.ac.uk)
It is generally accepted that benzimidazoles like triclabendazole bind to beta-tubulin and prevent the polymerisation of the microtubules of which they are part. (curezone.org)
The basic building block of microtubules is a heterodimer consisting of α- and β-tubulin . (wikilectures.eu)
During polymerization, the dimers are organized in such a way that α-tubulin is always adjacent to β-tubulin. (wikilectures.eu)

It is referred to as the mitotic spindle during mitosis, a process that produces genetically identical daughter cells, or the meiotic spindle during meiosis, a process that produces gametes with half the number of chromosomes of the parent cell. (wikipedia.org)
In fungi, spindles form between spindle pole bodies embedded in the nuclear envelope, which does not break down during mitosis. (wikipedia.org)
Find which symplekin supports devoted mitosis by simply causing occurance of your the disease spindle apparatus. (dchuskies.football)
These final results demonstrate a crucial eating habits study the polyadenylation devices along with mitosis along with advise that tumour tissue have an superior reliance upon these factors pertaining to spindle set up.Findings along with pc simulator numerous studies have exposed presence of rich character in the orientational peace regarding substances inside enclosed techniques including water back micelles, cyclodextrin oral cavaties, and also nanotubes. (dchuskies.football)
Recently, certain cancer chemotherapy agents have been found to exert their anticancer activities by disrupting the dynamics of microtubule assembly, thus perturbing the formation and function of the mitotic spindle apparatus and arresting cells in mitosis. (hsp90-inhibitors.com)
During mitosis, this polymerase activity may enhance spindle formation and stability and drive poleward flux. (elsevierpure.com)
Indeed, that such forces exist in C. elegans is evidenced by the maintenance of half-spindle lengths throughout mitosis 5 and in many perturbations experiments. (nature.com)
The protein encoded by this gene is a putative serine/threonine kinase that localizes to the mitotic apparatus and complexes with cell cycle controller CDC2 kinase in early mitosis. (cancerindex.org)
This compound stops cell mitosis by interfering with formation of the mitotic spindle and is often used for cytogenetic (chromosome) studies. (pediagenosis.com)

Besides chromosomes, the spindle apparatus is composed of hundreds of proteins. (wikipedia.org)
The growing ends of microtubules are protected against catastrophe by the action of plus-end microtubule tracking proteins (+TIPs) to promote their association with kinetochores at the midzone. (wikipedia.org)
CLIP-associated proteins like CLASP1 in humans have also been shown to localize to plus-ends and the outer kinetochore as well as to modulate the dynamics of kinetochore microtubules (Maiato 2003). (wikipedia.org)
Opposing the action of these microtubule-stabilizing proteins are a number of microtubule-depolymerizing factors which permit the dynamic remodeling of the mitotic spindle to promote chromosome congression and attainment of bipolarity. (wikipedia.org)
The kinesin-13 superfamily of MAPs contains a class of plus-end-directed motor proteins with associated microtubule depolymerization activity including the well-studied mammalian MCAK and Xenopus XKCM1. (wikipedia.org)
These proteins harness the energy of ATP hydrolysis to induce destabilizing conformational changes in protofilament structure that cause kinesin release and microtubule depolymerization. (wikipedia.org)
Depletion of symplekin attenuates microtubule polymerization action as well as phrase of the vital microtubule polymerization health proteins CKAP5 (TOGp). (dchuskies.football)
One implication is that regulation of Eg5 motile properties by regulatory proteins or small molecule inhibitors could also have effects on intracellular microtubule dynamics. (elsevierpure.com)
A network of membrane compartments, located at the cytoplasmic side of the GOLGI APPARATUS, where proteins and lipids are sorted for transport to various locations in the cell or cell membrane. (lookformedical.com)
All of these microtubules and their associated proteins are anchored to a basal body that is responsible for the formation of a core structure called the axoneme . (pediagenosis.com)
The stabilization of microtubules is ensured by the so-called ``accompanying proteins (proteins associated with microtubules, also ``MAPs ) by regulating polymerization and depolymerization. (wikilectures.eu)
Transport vesicles can move molecules between locations inside the cell, e.g., proteins from the rough endoplasmic reticulum to the Golgi apparatus . (wikipedia.org)
Most of these proteins mature in the Golgi apparatus before going to their final destination which may be to lysosomes , peroxisomes , or outside of the cell. (wikipedia.org)
00:03:51.11 And now we can take that same object 00:03:53.24 that you saw that Shinya Inoue described, 00:03:56.06 where he had observed 00:03:58.05 the mitotic spindle 00:03:59.27 with natural contrast 00:04:01.22 from the polarization microscope, 00:04:03.16 but now we can tag 00:04:05.11 specific proteins in the cell. (ibiology.org)

At the cellular level, the mitotic spindle apparatus is arguably the most complicated piece of machinery in existence. (piltdownsuperman.com)

Attachment of microtubules to chromosomes is mediated by kinetochores, which actively monitor spindle formation and prevent premature anaphase onset. (wikipedia.org)
in mammals, CLASP1 and CLASP2 both contribute to proper spindle assembly and microtubule dynamics in anaphase. (wikipedia.org)
Although the positioning signal is likely to be transmitted via the anaphase microtubule array to the cell cortex, exactly how the microtubule array determines the site of contractile ring formation remains unresolved. (biologists.com)
These data support a model in which Tum/RacGAP, via its interaction with Pbl, provides a critical link between the anaphase microtubule spindle and cytokinetic furrow formation in Drosophila cells. (biologists.com)
This tug-of-war resulted in chromosome-specific segregation errors during anaphase and revealed that spindle forces can heavily stretch chromosomal arms. (bvsalud.org)
RhoA, along with anaphase spindle fibers, also ensures that the contractile ring is formed at the right time, after chromosome segregation. (jove.com)

In all spindles, the microtubule cytoskeleton connects to chromosomes via a special class of microtubules called kinetochore microtubules (KMTs). (nature.com)
Microtubules are the thickest filaments of the cytoskeleton (25 nm in diameter). (wikilectures.eu)
In most eukaryotic cells the centrosome, composed of centrioles and associated pericentriolar material (PCM), acts as a major microtubule organizing center (MTOC) participating in the organization of both the interphase cytoskeleton and the mitotic spindle. (biomedcentral.com)

We employed Tet repressor or nuclease-dead Cas9 to link a microtubule minus-end-directed kinesin (Kinesin14VIb) from Physcomitrella patens to integrated Tet operon repeats and chromosome-specific endogenous repeats, respectively. (bvsalud.org)
Besides sliding apart antiparallel microtubules during spindle elongation, the mitotic kinesin-5, Eg5, promotes microtubule polymerization, emphasizing its importance in mitotic spindle length control. (elsevierpure.com)
Mitotic kinesin-5 (Eg5) motors promote microtubule polymerization through an unknown mechanism. (elsevierpure.com)

Microtubule polymerization and depolymerization dynamic drive chromosome congression. (wikipedia.org)
Polymerization - depolymerization of tobacco mosaic virus protein. (microbiologyresearch.org)
it is a mitotic spindle poison more potent than taxol, that increases the rate of microtubule assembly and inhibits depolymerization of microtubules. (liverpool.ac.uk)

In the wide middle portion, known as the spindle midzone, antiparallel microtubules are bundled by kinesins. (wikipedia.org)

Besides its organelles, the cytoplasm contains a network of microtubules, microfilaments, intermediate filaments, and thick filaments (Fig. 4.6). (pediagenosis.com)

CLIP170 was shown to localize near microtubule plus-ends in HeLa cells and to accumulate in kinetochores during prometaphase. (wikipedia.org)
MCAK localizes to the growing tips of microtubules at kinetochores where it can trigger catastrophe in direct competition with stabilizing +TIP activity. (wikipedia.org)
Thus, the unique mode of spindle formation in Xenos oocytes cannot be used to support the hypothesis that chromosomes (kinetochores) induce the polymerization of their associated MTs. (silverchair.com)
In the case of chromosomal origin, microtubules instead nucleate around chromosomes and only later attach to kinetochores, as observed in Xenopus cell-free extracts 13 . (nature.com)

protein motors of the microtubule system - ' kinesins and dyneins . (wikilectures.eu)

They are responsible for the formation of the highly organized core of microtubules found in cilia and flagella. (pediagenosis.com)
Cilia and flagella are microtubule-filled cellular extensions whose enclosing membrane is continuous with the cell membrane. (pediagenosis.com)
Recent evidence suggests that not all cilia contain this internal structure, and some may be missing the central pair of microtubules. (pediagenosis.com)
The Centrosome and the basal bodies of the cilia ( kinetosome ) represent the microtubules organizing the centers. (wikilectures.eu)

From these observations we conclude that the apparent individual chromosomal spindles--seen in the light microscope to form around each Xenos tetrad during "intranuclear prometaphase" (Hughes-Schrader, S., 1924, J. Morphol. (silverchair.com)
Knockdown or inhibition of Src induces multipolar spindle formation, resulting in abnormal expression of the Aurora B and INCENP components of the chromosomal passenger complex. (bvsalud.org)
Herein, Src and chromosomal passenger complex co-localize and Src inhibition impedes mitotic progression by inducing multipolar spindle formation. (bvsalud.org)

These components are known to participate in the formation of many cellular structures, such as the dynamic asters found in mitotic and meiotic spindles 3 , 4 . (sciforums.com)

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)

Kinesin14VIb-mediated pulling forces on the targeted chromosome were counteracted by forces from kinetochore-attached microtubules. (bvsalud.org)
This pole-to-chromosome relocation of the CIP2A-MDC1-TOPBP1 complex was impaired not only by depolymerizing microtubules but also by depleting CENP-A or HEC1, indicating that the kinetochore/centromere serves as a structural hub for microtubule-dependent transport of the CIP2A-MDC1-TOPBP1 complex. (bvsalud.org)
We classify them as kinetochore (KMTs), spindle (SMTs) or astral microtubules (AMTs) according to their positions, and quantify distinct properties of each class. (nature.com)

While our light microscopy and mutant studies show that microtubules are nucleated from the centrosomes, we find only a few KMTs directly connected to the centrosomes. (nature.com)

Intranuclear membranes and the formation of the first meiotic spindle in Xenos peckii (Acroschismus wheeleri) oocytes. (silverchair.com)

39:157-197)--actually form during late prophase, lack MTs, and are therefore not complete miniature bipolar spindles, as had been commonly assumed. (silverchair.com)

In dividing cells, the two cylindrical centrioles are initially found in the vicinity of the Golgi apparatus in a region of the cell called the centrosome . (pediagenosis.com)

Rab11 often links vesicles to molecular motors, and this study finds that loss of the microtubule motor dynein also leads to defective Neuroglian and Ppk26 degradation. (sdbonline.org)

This pool is used in the polymerization process for reassembly of the protofilaments. (pediagenosis.com)
Polymerization of these dimer molecules (with the participation of GTP) creates spirally arranged protofilaments , on which we distinguish (+) and (−) ends. (wikilectures.eu)
A microtubule is formed by a circular assembly of thirteen protofilaments. (wikilectures.eu)

The mitotic spindle ensures the faithful segregation of chromosomes. (nature.com)
The mitotic spindle is a dynamic microtubule-based apparatus that ensures the segregation of chromosomes during cell division. (nature.com)

The microtubule-associated protein Augmin acts in conjunction with γ-TURC to nucleate new microtubules off of existing microtubules. (wikipedia.org)

Purified motors and microtubules have previously been observed to form asters in vitro 5 . (sciforums.com)

The vinca alkaloid drugs ( e.g., vinblastine and vincristine), which are sometimes used in the treatment of cancer, also bind to microtubules and inhibit formation of the mitotic spindle, which is essential for cell proliferation. (pediagenosis.com)

In this instance, a Ran GTP gradient is the main regulator of spindle microtubule organization and assembly. (wikipedia.org)
Here we study the extent and the characteristics of self-organization using microtubules and molecular motors 2 as a model system. (sciforums.com)

The nature of mitotic spindle fibers and their role in chromosome movement. (microbiologyresearch.org)

RhoA promotes localized actin filament polymerization which is necessary for the contractile ring formation. (jove.com)

In cell biology, the spindle apparatus is the cytoskeletal structure of eukaryotic cells that forms during cell division to separate sister chromatids between daughter cells. (wikipedia.org)
In this paper, we set out to identify the cytoskeletal ultrastructure in C. elegans mitotic spindles that underlies this function, and how this ultrastructure is generated, using a combination of large-scale electron tomography, light microscopy and mathematical modelling. (nature.com)

Centrioles and basal bodies are structurally identical organelles composed of highly organized microtubules. (pediagenosis.com)
Internally, centrioles and basal bodies have an amorphous central core surrounded by clusters formed of triplet sets of microtubules. (pediagenosis.com)

their structures were elucidated using spectroscopic methods and their bioactivity was evaluated using an in vitro microtubule assembly assay. (liverpool.ac.uk)

The dynamic lengthening and shortening of spindle microtubules, through a process known as dynamic instability determines to a large extent the shape of the mitotic spindle and promotes the proper alignment of chromosomes at the spindle midzone. (wikipedia.org)

The ultrastructure of spindle formation during the first meiotic division in oocytes of the Strepsipteran insect Xenos peckii Kirby (Acroschismus wheeleri Pierce) was examined in serial thick (0.25-micron) and thin sections. (silverchair.com)
Our observation that MTs appeared in association with and parallel to tubular membrane components of the Xenos meiotic apparatus after these membranes became oriented with respect to the tetrads, is consistent with the notion that membranes associated with the spindle determine the orientation of spindle MTs and also play a part in regulating their formation. (silverchair.com)
00:04:12.03 with a red fluorescent protein, 00:04:14.00 and the chromosomes 00:04:15.17 with a green fluorescent protein, 00:04:17.14 and if you look at this 00:04:19.12 in a Drosophila embryo, 00:04:21.01 you can see the chromosomes, 00:04:23.04 the formation of the mitotic spindle, 00:04:25.28 and the physical motion 00:04:27.25 of these chromosomes here. (ibiology.org)

A motile cilium contains nine sets of doublet microtubules that form a hollow cylinder surrounding a central pair of singlet microtubules. (pediagenosis.com)

Indeed, by quantitatively analysing several models of microtubule growth, we conclude that minus-ends of KMTs have selectively detached and depolymerized from the centrosome. (nature.com)

Recruitment of γ-TuRC to the pericentrosomal region stabilizes microtubule minus-ends and anchors them near the microtubule-organizing center. (wikipedia.org)
Here we combine the first large-scale serial electron tomography of whole mitotic spindles in early C. elegans embryos with live-cell imaging to reconstruct all microtubules in 3D and identify their plus- and minus-ends. (nature.com)

The outer doublet microtubules contain ATP motor-driven complexes that cause the adjacent microtubule doublets to slide past each other. (pediagenosis.com)

They associate with microtubule bundles (MICROTUBULES) and are believed to produce mechanical force via a process linked to GTP hydrolysis. (lookformedical.com)

The (−) end anchors the microtubule in the microtubule-organizing center and growth does not occur on it. (wikilectures.eu)

Our data provide new insights into the critical crosstalk between chromosomes and spindle microtubules in response to DNA damage to maintain genomic stability during oocyte meiosis. (bvsalud.org)

The GAP activity of Tum is required for cytokinesis: in its absence cytokinesis fails early even though Tum is present on microtubules at the cell equator where the furrow should form. (biologists.com)
Disruption of the Pebble-interacting domain leaves Tum localised to the cell equator on cortically associated microtubules, again with no evidence of furrowing. (biologists.com)

Anatomy32

Organisms12

Chemicals and Drugs77

Analytical, Diagnostic and Therapeutic Techniques and Equipment12

Phenomena and Processes44

Technology, Industry, Agriculture3

Information Science4

Health Care1

Poles12

Tubulin17

Mitosis9

Proteins14

Mitotic spindle a1

Anaphase6

Cytoskeleton3

Kinesin3

Depolymerization3

Antiparallel microtubules1

Intermediate filaments1

Kinetochores4

Kinesins1

Cilia4

Chromosomal3

Cellular1

Chromosomes is mediated1

Kinetochore3

Centrosomes1

Meiotic spindle1

Bipolar1

GOLGI APPARATUS1

Dynein1

Protofilaments3

Segregation2

Nucleate1

Asters1

Bind1

Organization2

Fibers1

Actin filament polymerization1

Cytoskeletal2

Basal bodies2

Assembly1

Promotes1

Formation3

Motile cilium1

Centrosome1

Minus-ends2

Complexes1

Associate1

Anchors1

Stability1

Equator2