Cytokinesis in Scytosiphon zygotes - Journal of Cell Science
... KCl, 4.9 mM Na2HPO4, 1.5 mM KH2PO4, pH 7.4). The zygotes were slightly squashed between slide and coverslip to facilitate penetration of antibodies. Samples were treated with PBS containing 5% Triton X-100 for 60 minutes at room temperature and washed with PBS several times. Then they were incubated ...
... KCl, 4.9 mM Na2HPO4, 1.5 mM KH2PO4, pH 7.4). The zygotes were slightly squashed between slide and coverslip to facilitate penetration of antibodies. Samples were treated with PBS containing 5% Triton X-100 for 60 minutes at room temperature and washed with PBS several times. Then they were incubated ...
Molecular encounters at microtubule ends in the plant cell cortex
... protofilaments (’protofilament peeling’) are produced during MT shortening. MTs undergo dynamic instability, showing stochastic transitions between growing, pause and shrinking phases. When the minus end is anchored at its nucleation site, only the free plus end exhibits dynamic instability, but fre ...
... protofilaments (’protofilament peeling’) are produced during MT shortening. MTs undergo dynamic instability, showing stochastic transitions between growing, pause and shrinking phases. When the minus end is anchored at its nucleation site, only the free plus end exhibits dynamic instability, but fre ...
The functions of the cytoskeleton and associated
... an essential role in organizing MTs during tip growth (Hiwatashi et al., 2014). Consequently, these proteins likely contribute to the maintenance of the bipolar figure of MTs in phragmoplasts by promoting MT polymerization and/or stability. Further studies are needed to clarify the spatio-temporal an ...
... an essential role in organizing MTs during tip growth (Hiwatashi et al., 2014). Consequently, these proteins likely contribute to the maintenance of the bipolar figure of MTs in phragmoplasts by promoting MT polymerization and/or stability. Further studies are needed to clarify the spatio-temporal an ...
Chromosome Segregation in Budding Yeast: Sister Chromatid
... Address for correspondence: School of Biological Sciences, Michael Swann Building, Mayfield Rd., Edinburgh EH9 3JR, United Kingdom. E-mail: [email protected] ...
... Address for correspondence: School of Biological Sciences, Michael Swann Building, Mayfield Rd., Edinburgh EH9 3JR, United Kingdom. E-mail: [email protected] ...
Centrosome Maturation and Mitotic Spindle Assembly in C. elegans
... and mitosis fails. SPD-5 is required for the centrosomal localization of ␥-tubulin, XMAP-215, and Aurora A kinase family members, but SPD-5 accumulates at centrosomes in mutants lacking these proteins. Furthermore, SPD-5 interacts genetically with a dynein heavy chain. We propose that SPD-5, along w ...
... and mitosis fails. SPD-5 is required for the centrosomal localization of ␥-tubulin, XMAP-215, and Aurora A kinase family members, but SPD-5 accumulates at centrosomes in mutants lacking these proteins. Furthermore, SPD-5 interacts genetically with a dynein heavy chain. We propose that SPD-5, along w ...
High-throughput knockout screen in Schizosaccharomyces pombe
... nuclear movement and efficient pairing of homologous centromeres during meiotic prophase. Dynein-driven meiotic oscillatory nuclear movement is known to play a central role in recombination and pairing of homologs.20,28-31 The nuclear movement during meiotic prophase in fission yeast results in a ty ...
... nuclear movement and efficient pairing of homologous centromeres during meiotic prophase. Dynein-driven meiotic oscillatory nuclear movement is known to play a central role in recombination and pairing of homologs.20,28-31 The nuclear movement during meiotic prophase in fission yeast results in a ty ...
10 m
... microtubules and associated proteins It controls chromosome movement during mitosis In animal cells, assembly of spindle microtubules begins in the centrosome, a type of microtubule organizing center ...
... microtubules and associated proteins It controls chromosome movement during mitosis In animal cells, assembly of spindle microtubules begins in the centrosome, a type of microtubule organizing center ...
-Tubulin Plays an Essential Role in the Coordination of Mitotic Events
... germinating conidia (uninucleate asexual spores), which are arrested in G1 before germination. Incubation of conidia of the mipAD159/nimT23 strain at 43°C allowed them to germinate and proceed through the cell cycle until they were arrested in late G2 by nimT23. They were then shifted rapidly from 4 ...
... germinating conidia (uninucleate asexual spores), which are arrested in G1 before germination. Incubation of conidia of the mipAD159/nimT23 strain at 43°C allowed them to germinate and proceed through the cell cycle until they were arrested in late G2 by nimT23. They were then shifted rapidly from 4 ...
Preview Sample 1
... chromosomal pairs. The "m" superscript indicates that the homolog is maternally derived, while the "p" indicates a paternally derived homolog. Assume that in the genus Culex, the sex chromosomes are morphologically identical. (a) For each of the cell types given below, draw and label (with reference ...
... chromosomal pairs. The "m" superscript indicates that the homolog is maternally derived, while the "p" indicates a paternally derived homolog. Assume that in the genus Culex, the sex chromosomes are morphologically identical. (a) For each of the cell types given below, draw and label (with reference ...
CDK11p58 kinase activity is required to protect sister chromatid
... Internal ribosomal entry site ...
... Internal ribosomal entry site ...
the fine structure of the mid-body of the rat
... membrane (Fig. 7). Even in images of such a late stage, the fibrillary material of the spindle is usually seen running from the bridge into the adjoining cytoplasm of the daughter cells (Figs. 5 to 7). The final process of the rupture of the bridge is not conveniently studied in thin sections becaus ...
... membrane (Fig. 7). Even in images of such a late stage, the fibrillary material of the spindle is usually seen running from the bridge into the adjoining cytoplasm of the daughter cells (Figs. 5 to 7). The final process of the rupture of the bridge is not conveniently studied in thin sections becaus ...
cleeks o` cytokinesis: microtubule sticks and contractile hoops in cell
... Cytokinesis in Drosophila spermatocytes One difficulty in using genetic approaches to study cell division is the fact that many proteins that have a particular role in prometaphase are reutilized for different ends during cytokinesis. Thus mutants for such proteins tend to show metaphase arrest in m ...
... Cytokinesis in Drosophila spermatocytes One difficulty in using genetic approaches to study cell division is the fact that many proteins that have a particular role in prometaphase are reutilized for different ends during cytokinesis. Thus mutants for such proteins tend to show metaphase arrest in m ...
Gene nuc2 - The Journal of Cell Biology
... then transferred to restrictive temperature (36~ for 4 h and examined by DAPI stain for whether chromosomes of ts mutant cells remain condensed without separation. In the wild-type S. pombe, chromosomes separate after condensation (e.g., Toda et al., 1981). Therefore, if mutations specifically preve ...
... then transferred to restrictive temperature (36~ for 4 h and examined by DAPI stain for whether chromosomes of ts mutant cells remain condensed without separation. In the wild-type S. pombe, chromosomes separate after condensation (e.g., Toda et al., 1981). Therefore, if mutations specifically preve ...
Centrosomes as Scaffolds - Albert Einstein College of Medicine
... material either diffused throughout the cytoplasm or specifically localized around centrioles. The centrosome serves as the cell’s MTOC, a dynamic structure that assumes different forms and locations depending on the cell cycle phase (Brinkley, 1985). During the G1 phase of the cell cycle the centro ...
... material either diffused throughout the cytoplasm or specifically localized around centrioles. The centrosome serves as the cell’s MTOC, a dynamic structure that assumes different forms and locations depending on the cell cycle phase (Brinkley, 1985). During the G1 phase of the cell cycle the centro ...
Meiosis II
... Meiosis I results in two The chromosomes line up in a The sister chromatids haploid (N) daughter cells, similar way to the metaphase separate and move toward each with half the number of stage of mitosis. opposite ends of the cell. chromosomes as the original. ...
... Meiosis I results in two The chromosomes line up in a The sister chromatids haploid (N) daughter cells, similar way to the metaphase separate and move toward each with half the number of stage of mitosis. opposite ends of the cell. chromosomes as the original. ...
Identification of a Mid-anaphase Checkpoint in
... Studies in populations of budding yeast, after activation of a facultative, dicentric chromosome are also indicative of a mid-anaphase cell cycle checkpoint which can delay progression through mitosis (Neff and Burke, 1992; Brock and Bloom, 1994). These dicentric chromosomes contain two centromeres, ...
... Studies in populations of budding yeast, after activation of a facultative, dicentric chromosome are also indicative of a mid-anaphase cell cycle checkpoint which can delay progression through mitosis (Neff and Burke, 1992; Brock and Bloom, 1994). These dicentric chromosomes contain two centromeres, ...
A High Throughput, Whole Cell Screen for Small
... Dr. Aldo Tarricone (European Institute of Oncology, Milan, Italy). Bub1:Bub3 complex and Mps1 kinase were expressed in, and purified from, Sf9 insect cells infected with recombinant baculoviruses. The complex was isolated on Ni-NTA beads and further purified by size-exclusion chromatography. ...
... Dr. Aldo Tarricone (European Institute of Oncology, Milan, Italy). Bub1:Bub3 complex and Mps1 kinase were expressed in, and purified from, Sf9 insect cells infected with recombinant baculoviruses. The complex was isolated on Ni-NTA beads and further purified by size-exclusion chromatography. ...
Microtubules and the Evolution of Mitosis
... and transcription, would be advantageous in such a multi-chromosome constellation. This might have been the driving force for the development of a nuclear envelope. The mechanisms of chromosomal segregation in mycoplasm should, therefore, recapitulate some aspects of this very early stage of mitotic ...
... and transcription, would be advantageous in such a multi-chromosome constellation. This might have been the driving force for the development of a nuclear envelope. The mechanisms of chromosomal segregation in mycoplasm should, therefore, recapitulate some aspects of this very early stage of mitotic ...
Fission Yeast Bub1 Is a Mitotic Centromere Protein Essential for the
... together at an early step in the checkpoint pathway, upstream of all the other Bub and Mad proteins (Farr and Hoyt, 1998). In addition to gross alterations in spindle structure, the budding yeast spindle checkpoint can also respond to low doses of microtubule depolymerizing drugs, to defects in- ...
... together at an early step in the checkpoint pathway, upstream of all the other Bub and Mad proteins (Farr and Hoyt, 1998). In addition to gross alterations in spindle structure, the budding yeast spindle checkpoint can also respond to low doses of microtubule depolymerizing drugs, to defects in- ...
- Opus
... Mitosis is a fundamental biological process found in all cellular organisms. During mitosis in animal cells the centrosomes organize microtubule networks to establish the mitotic spindle. This requires the cooperation of several processes including microtubule nucleation, stability, and anchorage. I ...
... Mitosis is a fundamental biological process found in all cellular organisms. During mitosis in animal cells the centrosomes organize microtubule networks to establish the mitotic spindle. This requires the cooperation of several processes including microtubule nucleation, stability, and anchorage. I ...
Mutations in the Drosophila Condensin Subunit
... ditis elegans, mutations in SMC4 show condensation defects at prometaphase, but little effect on condensation at metaphase and anaphase (Hagstrom et al. 2002). This is similar to observations in chicken cells lacking ScII/SMC2 in which chromosome condensation is delayed, but eventually reaches norma ...
... ditis elegans, mutations in SMC4 show condensation defects at prometaphase, but little effect on condensation at metaphase and anaphase (Hagstrom et al. 2002). This is similar to observations in chicken cells lacking ScII/SMC2 in which chromosome condensation is delayed, but eventually reaches norma ...
A conserved role for kinesin-5 in plant mitosis
... spindle requires opposing forces, generated by motor proteins pushing in opposite directions on spindle microtubules. At the mid-zone, plus-end-directed motors push the poles apart by cross-linking anti-parallel microtubules and walking to their plus ends; while at the pole, minus-end-directed motor ...
... spindle requires opposing forces, generated by motor proteins pushing in opposite directions on spindle microtubules. At the mid-zone, plus-end-directed motors push the poles apart by cross-linking anti-parallel microtubules and walking to their plus ends; while at the pole, minus-end-directed motor ...
Cell Cycle
... The mitotic spindle is a structure made of microtubules and associated proteins ...
... The mitotic spindle is a structure made of microtubules and associated proteins ...
Kinetochore
The kinetochore /kɪˈnɛtəkɔər/ is the protein structure on chromatids where the spindle fibers attach during cell division to pull sister chromatids apart.The kinetochore forms in eukaryotes, assembles on the centromere and links the chromosome to microtubule polymers from the mitotic spindle during mitosis and meiosis.""Monocentric"" organisms, including vertebrates, fungi, and most plants, have a single centromeric region on each chromosome which assembles one kinetochore. ""Holocentric"" organisms, such as nematodes and some plants, assemble a kinetochore along the entire length of a chromosome.The kinetochore contains two regions: an inner kinetochore, which is tightly associated with the centromere DNA, assembled in a specialized form of chromatin persistent throughout the cell cycle; an outer kinetochore, which interacts with microtubules; the outer kinetochore is a very dynamic structure, with many identical components, which are assembled and functional only during cell division.Kinetochores start, control and supervise the striking movements of chromosomes during cell division. During mitosis, which occurs after chromosomes are duplicated during S phase, two sister chromatids are held together each with its own kinetochore which face in opposing directions and attach to opposite poles of the mitotic spindle. Following the transition from metaphase to anaphase, the sister chromatids separate from each other, and the individual kinetochores on each chromatid drive their movement to the spindle poles that will define the two new daughter cells. Thus, the kinetochore is essential for the chromosome segregation that is classically associated with mitosis and meiosis.Even the simplest kinetochores consist of more than 19 different proteins. Many of these proteins are conserved between eukaryotic species, including a specialized histone H3 variant (called CENP-A or CenH3) which helps the kinetochore associate with DNA. Other proteins in the kinetochore attach it to the microtubules (MTs) of the mitotic spindle. There are also motor proteins, including both dynein and kinesin, which generate forces that move chromosomes during mitosis. Other proteins, such as MAD2 monitor the microtubule attachment as well as the tension between sister kinetochores and activate the spindle checkpoint to arrest the cell cycle when either of these is absent.In summary, kinetochore functions include anchoring of chromosomes to MTs in the spindle, verification of anchoring, activation of the spindle checkpoint and participation in force generation to propel chromosome movement during cell division.On the other hand, MTs are metastable polymers made of α- and β-tubulin, alternating between growing and shrinking phases, a phenomenon known as ""dynamic instability"". MTs are highly dynamic structures, whose behavior is integrated with kinetochore function to control chromosome movement and segregation.