Artykuły w czasopismach: „Cleavage furrow formation”

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Onishi, Masayuki, James G. Umen, Frederick R. Cross i John R. Pringle. "Cleavage-furrow formation without F-actin inChlamydomonas". Proceedings of the National Academy of Sciences 117, nr 31 (20.07.2020): 18511–20. http://dx.doi.org/10.1073/pnas.1920337117.

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It is widely believed that cleavage-furrow formation during cytokinesis is driven by the contraction of a ring containing F-actin and type-II myosin. However, even in cells that have such rings, they are not always essential for furrow formation. Moreover, many taxonomically diverse eukaryotic cells divide by furrowing but have no type-II myosin, making it unlikely that an actomyosin ring drives furrowing. To explore this issue further, we have used one such organism, the green algaChlamydomonas reinhardtii. We found that although F-actin is associated with the furrow region, none of the three myosins (of types VIII and XI) is localized there. Moreover, when F-actin was eliminated through a combination of a mutation and a drug, furrows still formed and the cells divided, although somewhat less efficiently than normal. Unexpectedly, division of the largeChlamydomonaschloroplast was delayed in the cells lacking F-actin; as this organelle lies directly in the path of the cleavage furrow, this delay may explain, at least in part, the delay in cytokinesis itself. Earlier studies had shown an association of microtubules with the cleavage furrow, and we used a fluorescently tagged EB1 protein to show that microtubules are still associated with the furrows in the absence of F-actin, consistent with the possibility that the microtubules are important for furrow formation. We suggest that the actomyosin ring evolved as one way to improve the efficiency of a core process for furrow formation that was already present in ancestral eukaryotes.

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Muto, A., S. Kume, T. Inoue, H. Okano i K. Mikoshiba. "Calcium waves along the cleavage furrows in cleavage-stage Xenopus embryos and its inhibition by heparin." Journal of Cell Biology 135, nr 1 (1.10.1996): 181–90. http://dx.doi.org/10.1083/jcb.135.1.181.

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Calcium signaling is known to be associated with cytokinesis; however, the detailed spatio-temporal pattern of calcium dynamics has remained unclear. We have studied changes of intracellular free calcium in cleavage-stage Xenopus embryos using fluorescent calcium indicator dyes, mainly Calcium Green-1. Cleavage formation was followed by calcium transients that localized to cleavage furrows and propagated along the furrows as calcium waves. The calcium transients at the cleavage furrows were observed at each cleavage furrow at least until blastula stage. The velocity of the calcium waves at the first cleavage furrow was approximately 3 microns/s, which was much slower than that associated with fertilization/egg activation. These calcium waves traveled only along the cleavage furrows and not in the direction orthogonal to the furrows. These observations imply that there exists an intracellular calcium-releasing activity specifically associated with cleavage furrows. The calcium waves occurred in the absence of extracellular calcium and were inhibited in embryos injected with heparin an inositol 1,4,5-trisphosphate (InsP3) receptor antagonist. These results suggest that InsP3 receptor-mediated calcium mobilization plays an essential role in calcium wave formation at the cleavage furrows.

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Albertson, Roger, Jian Cao, Tao-shih Hsieh i William Sullivan. "Vesicles and actin are targeted to the cleavage furrow via furrow microtubules and the central spindle". Journal of Cell Biology 181, nr 5 (26.05.2008): 777–90. http://dx.doi.org/10.1083/jcb.200803096.

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During cytokinesis, cleavage furrow invagination requires an actomyosin-based contractile ring and addition of new membrane. Little is known about how this actin and membrane traffic to the cleavage furrow. We address this through live analysis of fluorescently tagged vesicles in postcellularized Drosophila melanogaster embryos. We find that during cytokinesis, F-actin and membrane are targeted as a unit to invaginating furrows through formation of F-actin–associated vesicles. F-actin puncta strongly colocalize with endosomal, but not Golgi-derived, vesicles. These vesicles are recruited to the cleavage furrow along the central spindle and a distinct population of microtubules (MTs) in contact with the leading furrow edge (furrow MTs). We find that Rho-specific guanine nucleotide exchange factor mutants, pebble (pbl), severely disrupt this F-actin–associated vesicle transport. These transport defects are a consequence of the pbl mutants' inability to properly form furrow MTs and the central spindle. Transport of F-actin–associated vesicles on furrow MTs and the central spindle is thus an important mechanism by which actin and membrane are delivered to the cleavage furrow.

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Sherlekar, Aparna, i Richa Rikhy. "Syndapin promotes pseudocleavage furrow formation by actin organization in the syncytial Drosophila embryo". Molecular Biology of the Cell 27, nr 13 (lipiec 2016): 2064–79. http://dx.doi.org/10.1091/mbc.e15-09-0656.

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Coordinated membrane and cytoskeletal remodeling activities are required for membrane extension in processes such as cytokinesis and syncytial nuclear division cycles in Drosophila. Pseudocleavage furrow membranes in the syncytial Drosophila blastoderm embryo show rapid extension and retraction regulated by actin-remodeling proteins. The F-BAR domain protein Syndapin (Synd) is involved in membrane tubulation, endocytosis, and, uniquely, in F-actin stability. Here we report a role for Synd in actin-regulated pseudocleavage furrow formation. Synd localized to these furrows, and its loss resulted in short, disorganized furrows. Synd presence was important for the recruitment of the septin Peanut and distribution of Diaphanous and F-actin at furrows. Synd and Peanut were both absent in furrow-initiation mutants of RhoGEF2 and Diaphanous and in furrow-progression mutants of Anillin. Synd overexpression in rhogef2 mutants reversed its furrow-extension phenotypes, Peanut and Diaphanous recruitment, and F-actin organization. We conclude that Synd plays an important role in pseudocleavage furrow extension, and this role is also likely to be crucial in cleavage furrow formation during cell division.

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Noguchi, Tatsuhiko, i Issei Mabuchi. "Localized Calcium Signals along the Cleavage Furrow of theXenopus Egg Are Not Involved in Cytokinesis". Molecular Biology of the Cell 13, nr 4 (kwiecień 2002): 1263–73. http://dx.doi.org/10.1091/mbc.01-10-0501.

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It has been proposed that a localized calcium (Ca) signal at the growing end of the cleavage furrow triggers cleavage furrow formation in large eggs. We have examined the possible role of a Ca signal in cleavage furrow formation in the Xenopus laevis egg during the first cleavage. We were able to detect two kinds of Ca waves along the cleavage furrow. However, the Ca waves appeared after cleavage furrow formation in late stages of the first cleavage. In addition, cleavage was not affected by injection of dibromoBAPTA or EGTA into the eggs at a concentration sufficient to suppress the Ca waves. Furthermore, even smaller classes of Ca release such as Ca puffs and Ca blips do not occur at the growing end of the cleavage furrow. These observations demonstrate that localized Ca signals in the cleavage furrow are not involved in cytokinesis. The two Ca waves have unique characteristics. The first wave propagates only in the region of newly inserted membrane along the cleavage furrow. On the other hand, the second wave propagates along the border of new and old membranes, suggesting that this wave might be involved in adhesion between two blastomeres.

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Eckley, D. Mark, Alexandra M. Ainsztein, Alastair M. Mackay, Ilya G. Goldberg i William C. Earnshaw. "Chromosomal Proteins and Cytokinesis: Patterns of Cleavage Furrow Formation and Inner Centromere Protein Positioning in Mitotic Heterokaryons and Mid-anaphase Cells". Journal of Cell Biology 136, nr 6 (24.03.1997): 1169–83. http://dx.doi.org/10.1083/jcb.136.6.1169.

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After the separation of sister chromatids in anaphase, it is essential that the cell position a cleavage furrow so that it partitions the chromatids into two daughter cells of roughly equal size. The mechanism by which cells position this cleavage furrow remains unknown, although the best current model is that furrows always assemble midway between asters. We used micromanipulation of human cultured cells to produce mitotic heterokaryons with two spindles fused in a V conformation. The majority (15/19) of these cells cleaved along a single plane that transected the two arms of the V at the position where the metaphase plate had been, a result at odds with current views of furrow positioning. However, four cells did form an additional ectopic furrow between the spindle poles at the open end of the V, consistent with the established view. To begin to address the mechanism of furrow assembly, we have begun a detailed study of the properties of the chromosome passenger inner centromere protein (INCENP) in anaphase and telophase cells. We found that INCENP is a very early component of the cleavage furrow, accumulating at the equatorial cortex before any noticeable cortical shape change and before any local accumulation of myosin heavy chain. In mitotic heterokaryons, INCENP was detected in association with spindle midzone microtubules beneath sites of furrowing and was not detected when furrows were absent. A functional role for INCENP in cytokinesis was suggested in experiments where a nearly full-length INCENP was tethered to the centromere. Many cells expressing the chimeric INCENP failed to complete cytokinesis and entered the next cell cycle with daughter cells connected by a large intercellular bridge with a prominent midbody. Together, these results suggest that INCENP has a role in either the assembly or function of the cleavage furrow.

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Su, Jing, Brenda Chow, Gabrielle L. Boulianne i Andrew Wilde. "The BAR domain of amphiphysin is required for cleavage furrow tip–tubule formation during cellularization in Drosophila embryos". Molecular Biology of the Cell 24, nr 9 (maj 2013): 1444–53. http://dx.doi.org/10.1091/mbc.e12-12-0878.

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De novo formation of cells in the Drosophila embryo is achieved when each nucleus is surrounded by a furrow of plasma membrane. Remodeling of the plasma membrane during cleavage furrow ingression involves the exocytic and endocytic pathways, including endocytic tubules that form at cleavage furrow tips (CFT-tubules). The tubules are marked by amphiphysin but are otherwise poorly understood. Here we identify the septin family of GTPases as new tubule markers. Septins do not decorate CFT-tubules homogeneously: instead, novel septin complexes decorate different CFT-tubules or different domains of the same CFT-tubule. Using these new tubule markers, we determine that all CFT-tubule formation requires the BAR domain of amphiphysin. In contrast, dynamin activity is preferentially required for the formation of the subset of CFT-tubules containing the septin Peanut. The absence of tubules in amphiphysin-null embryos correlates with faster cleavage furrow ingression rates. In contrast, upon inhibition of dynamin, longer tubules formed, which correlated with slower cleavage furrow ingression rates. These data suggest that regulating the recycling of membrane within the embryo is important in supporting timely furrow ingression.

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Liu, Zairan, i Orion D. Weiner. "Positioning the cleavage furrow: All you need is Rho". Journal of Cell Biology 213, nr 6 (20.06.2016): 605–7. http://dx.doi.org/10.1083/jcb.201606010.

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RhoA controls cleavage furrow formation during cell division, but whether RhoA suffices to orchestrate spatiotemporal dynamics of furrow formation is unknown. In this issue, Wagner and Glotzer (2016. J. Cell Biol. http://dx.doi.org/10.1083/jcb.201603025) show that RhoA activity can induce furrow formation in all cell cortex positions and cell cycle phases.

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MABUCHI, ISSEI. "Cleavage Furrow Formation and Actin-Modulating Proteins". Annals of the New York Academy of Sciences 582, nr 1 Cytokinesis (kwiecień 1990): 131. http://dx.doi.org/10.1111/j.1749-6632.1990.tb21674.x.

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Sewall, Tommy C., i Jeffrey C. Pommerville. "The role of endoplasmic reticulum during gametogenesis in the aquatic fungus Allomyces macrogynus". Canadian Journal of Botany 69, nr 2 (1.02.1991): 336–41. http://dx.doi.org/10.1139/b91-045.

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The Chytridiomycete Allomyces macrogynus generates new membranes for cleavage furrow and nuclear-cap formation during gametogenesis and zoosporogenesis. Transmission electron microscopy after impregnation with a mixture of zinc iodide and osmium tetroxide clearly demonstrated changes in the endoplasmic reticulum. Endoplasmic reticulum was intensely stained but did not appear to contribute to the formation of the unstained flagellar membranes or cleavage furrows. However, the relative cytoplasmic volume of endoplasmic reticulum decreased as positively stained nuclear-cap membrane formed. These observations are consistent with the hypothesis that flagellar membranes and cleavage furrows are derived from trans-Golgi equivalents, whereas the nuclear-cap membrane is derived from the endoplasmic reticulum. Key words: Allomyces macrogynus, Chytridiomycetes, endoplasmic reticulum, gametogenesis, zoosporogenesis.

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Onishi, Masayuki, Nolan Ko, Ryuichi Nishihama i John R. Pringle. "Distinct roles of Rho1, Cdc42, and Cyk3 in septum formation and abscission during yeast cytokinesis". Journal of Cell Biology 202, nr 2 (22.07.2013): 311–29. http://dx.doi.org/10.1083/jcb.201302001.

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In yeast and animal cytokinesis, the small guanosine triphosphatase (GTPase) Rho1/RhoA has an established role in formation of the contractile actomyosin ring, but its role, if any, during cleavage-furrow ingression and abscission is poorly understood. Through genetic screens in yeast, we found that either activation of Rho1 or inactivation of another small GTPase, Cdc42, promoted secondary septum (SS) formation, which appeared to be responsible for abscission. Consistent with this hypothesis, a dominant-negative Rho1 inhibited SS formation but not cleavage-furrow ingression or the concomitant actomyosin ring constriction. Moreover, Rho1 is temporarily inactivated during cleavage-furrow ingression; this inactivation requires the protein Cyk3, which binds Rho1-guanosine diphosphate via its catalytically inactive transglutaminase-like domain. Thus, unlike the active transglutaminases that activate RhoA, the multidomain protein Cyk3 appears to inhibit activation of Rho1 (and thus SS formation), while simultaneously promoting cleavage-furrow ingression through primary septum formation. This work suggests a general role for the catalytically inactive transglutaminases of fungi and animals, some of which have previously been implicated in cytokinesis.

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Werner, Michael, i Michael Glotzer. "Control of cortical contractility during cytokinesis". Biochemical Society Transactions 36, nr 3 (21.05.2008): 371–77. http://dx.doi.org/10.1042/bst0360371.

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Cleavage furrow formation in animal cells results from a local increase in cortical contractility. During anaphase, the spindle contains, in addition to astral arrays of microtubules, a set of bundled microtubules known as the central spindle. Each of these populations of microtubules, the astral arrays and the central spindle bundles, is sufficient to direct cleavage furrow formation, yet in wild-type situations these sets of microtubules co-operate to induce furrow formation at the same site, between the segregating chromosomes. These pathways have distinct genetic requirements that reflect their differential control of cortical actomyosin. We review our current understanding of the molecular mechanisms of furrow formation, with particular emphasis on the central spindle-independent pathway.

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Neujahr, R., R. Albrecht, J. Kohler, M. Matzner, J. M. Schwartz, M. Westphal i G. Gerisch. "Microtubule-mediated centrosome motility and the positioning of cleavage furrows in multinucleate myosin II-null cells". Journal of Cell Science 111, nr 9 (1.05.1998): 1227–40. http://dx.doi.org/10.1242/jcs.111.9.1227.

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To study centrosome motility and the interaction of microtubules with the cell cortex in mitotic, post-mitotic and interphase cells, (alpha)-tubulin was tagged in Dictyostelium discoideum with green fluorescent protein. Multinucleate cells formed by myosin II-null mutants proved to be especially suited for the analysis of the control of cleavage furrow formation by the microtubule system. After docking of the mitotic apparatus onto the cell cortex during anaphase, the cell surface is activated to form ruffles on top of the asters of microtubules that emanate from the centrosomes. Cleavage furrows are initiated at spaces between the asters independently of the positions of spindles. Once initiated, the furrows expand as deep folds without a continued connection to the microtubule system. Occurrence of unilateral furrows indicates that a closed contractile ring is dispensable for cytokinesis in Dictyostelium. The progression of cytokinesis in the multinucleate cells underlines the importance of proteins other than myosin II in specifying a cleavage furrow. The analysis of centrosome motility suggests a major role for a minus-end directed motor protein, probably cytoplasmic dynein, in applying traction forces on guiding microtubules that connect the centrosome with the cell cortex.

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Fluck, R. A., A. L. Miller i L. F. Jaffe. "Slow calcium waves accompany cytokinesis in medaka fish eggs." Journal of Cell Biology 115, nr 5 (1.12.1991): 1259–65. http://dx.doi.org/10.1083/jcb.115.5.1259.

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Animal cells are cleaved by the formation and contraction of an extremely thin actomyosin band. In most cases this contractile band seems to form synchronously around the whole equator of the cleaving cell; however in giant cells it first forms near the mitotic apparatus and then slowly grows outwards over the cell. We studied the relationship of calcium to such contractile band growth using aequorin injected medaka fish eggs: we see two successive waves of faint luminescence moving along each of the first three cleavage furrows at approximately 0.5 micron/s. The first, narrower waves accompany furrow extension, while the second, broader ones, accompany the subsequent apposition or slow zipping together of the separating cells. If the first waves travel within the assembling contractile band, they would indicate local increases of free calcium to concentrations of about five to eight micromolar. This is the first report to visualize high free calcium within cleavage furrows. Moreover, this is also the first report to visualize slow (0.3-1.0 micron/s) as opposed to fast (10-100 microns/s) calcium waves. We suggest that these first waves are needed for furrow growth; that in part they further furrow growth by speeding actomyosin filament shortening, while such shortening in turn acts to mechanically release calcium and thus propagates these waves as well as furrow growth. We also suggest that the second waves act to induce the exocytosis which provides new furrow membrane.

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Martineau, S. N., P. R. Andreassen i R. L. Margolis. "Delay of HeLa cell cleavage into interphase using dihydrocytochalasin B: retention of a postmitotic spindle and telophase disc correlates with synchronous cleavage recovery." Journal of Cell Biology 131, nr 1 (1.10.1995): 191–205. http://dx.doi.org/10.1083/jcb.131.1.191.

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The molecular signals that determine the position and timing of the cleavage furrow during mammalian cell cytokinesis are presently unknown. We have studied in detail the effect of dihydrocytochalasin B (DCB), a drug that interferes with actin assembly, on specific late mitotic events in synchronous HeLa cells. When cleavage furrow formation is blocked at 10 microM DCB, cells return to interphase by the criteria of reformation of nuclei with lamin borders, degradation of the cyclin B component of p34cdc2 kinase, and loss of mitosis specific MPM-2 antigens. However, the machinery for cell cleavage is retained for up to one hour into G1 when cleavage cannot proceed. The components retained consist prominently of a "postmitotic" spindle and a telophase disc, a structure templated by the mitotic spindle in anaphase that may determine the position and timing of the cleavage furrow. Upon release from DCB block, G1 cells proceed through a rapid and synchronous cleavage. We conclude that the mitotic spindle is not inevitably destroyed at the end of mitosis, but persists as an integral structure with the telophase disc in the absence of cleavage. We also conclude that cell cleavage can occur in G1, and is therefore an event metabolically independent of mitosis. The retained telophase disc may indeed signal the position of furrow formation, as G1 cleavage occurs only in the position where the retained disc underlies the cell cortex. The protocol we describe should now enable development of a model system for the study of mammalian cell cleavage as a synchronous event independent of mitosis.

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Noguchi, T., i I. Mabuchi. "Reorganization of actin cytoskeleton at the growing end of the cleavage furrow of Xenopus egg during cytokinesis". Journal of Cell Science 114, nr 2 (15.01.2001): 401–12. http://dx.doi.org/10.1242/jcs.114.2.401.

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We studied reorganization of actin-myosin cytoskeleton at the growing ends of the cleavage furrow of Xenopus eggs in order to understand how the contractile ring is formed during cytokinesis. Reorganization of F-actin structures during the furrow formation was demonstrated by rhodamine-phalloidin staining of the cleavage furrow and by time-lapse scanning with laser scanning microscopy of F-actin structures in the cleavage furrow of live eggs to which rhodamine-G-actin had been injected. Actin filaments assemble to form small clusters that we call ‘F-actin patches’ at the growing end of the furrow. In live recordings, we observed emergence and rapid growth of F-actin patches in the furrow region. These patches then align in tandem, elongate and fuse with each other to form short F-actin bundles. The short bundles then form long F-actin bundles that compose the contractile ring. During the furrow formation, a cortical movement towards the division plane occurs at the growing ends of the furrow, as shown by monitoring wheatgerm agglutinin-conjugated fluorescent beads attached to the egg surface. As a result, wheatgerm agglutinin-binding sites accumulate and form ‘bleb-like’ structures on the surface of the furrow region. The F-actin patch forms and grows underneath this structure. The slope of F-actin accumulation in the interior region of the furrow exceeds that of accumulation of the cortex transported by the cortical movement. In addition, rhodamine-G-actin microinjected at the growing end is immediately incorporated into the F-actin patches. These data, together with the rapid growth of F-actin patches in the live image, suggest that actin polymerization occurs in the contractile ring formation. Distribution of myosin II in the cleavage furrow was also examined by immunofluorescence microscopy. Myosin II assembles as spots at the growing end underneath the bleb-like structure. It was suggested that myosin is transported and accumulates as spots by way of the cortical movement. F-actin accumulates at the position of the myosin spot a little later as the F-actin patches. The myosin spots and the F-actin patches are then simultaneously reorganized to form the contractile ring bundles

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Levi, Mattan, Bernard Maro i Ruth Shalgi. "Fyn kinase is involved in cleavage furrow ingression during meiosis and mitosis". REPRODUCTION 140, nr 6 (grudzień 2010): 827–34. http://dx.doi.org/10.1530/rep-10-0312.

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Fertilization of mammalian oocytes triggers their exit from the second meiotic division metaphase arrest. The extrusion of the second polar body (PBII) that marks the completion of meiosis is followed by the first mitotic cleavage of the zygote. Several lines of evidence in somatic cells imply the involvement of Fyn, an Src family kinase (SFK), in cell cycle control and actin functions. In this study, we demonstrate, using live cell confocal imaging and microinjection of Fyn cRNAs, the recruitment of Fyn to the oocyte's cortical area overlying the chromosomes and its colocalization with filamentous actin (F-actin) during exit from the meiotic metaphase. Fyn concentrated asymmetrically at the cortical site designated for ingression of the PBII cleavage furrow, where F-actin had already been accumulated, and then redispersed throughout the entire cortex only to be recruited again to the cleavage furrow during the first mitotic division. Although microinjection of dominant negative Fyn did not affect initiation of the cleavage furrow, it prolonged the average duration of ingression, decreased the rates of PB extrusion and of the first cleavage, and led to the formation of bigger PBs and longer spindles. Extrusion of the PBII was blocked in oocytes exposed to SU6656, an SFK inhibitor. Our results demonstrate, for the first time, a continuous colocalization of Fyn and F-actin during meiosis and imply a role for the SFKs, in general, and for Fyn, in particular, in regulating pathways that involve actin cytoskeleton, during ingression of the meiotic and mitotic cleavage furrows.

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Byers, T. J., i P. B. Armstrong. "Membrane protein redistribution during Xenopus first cleavage." Journal of Cell Biology 102, nr 6 (1.06.1986): 2176–84. http://dx.doi.org/10.1083/jcb.102.6.2176.

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A large increase in surface area must accompany formation of the amphibian embryo first cleavage furrow. The additional membrane for this areal expansion has been thought to be provided entirely from cytoplasmic stores during furrowing. We have radioiodinated surface proteins of fertilized, precleavage Xenopus laevis embryos and followed their redistribution during first cleavage by autoradiography. Near the end of first cleavage, membrane of the outer, pigmented surface of the embryo and a short band of membrane at the leading edge of the furrow displayed a high silver grain density, but the remainder of the furrow membrane was lightly labeled. The membrane of the cleavage furrow is thus mosaic in character; the membrane at the leading edge originates in part from the surface of the zygote, but most of the membrane lining the furrow walls is derived from a source inaccessible to surface radioiodination. The furrow membrane adjacent to the outer, pigmented surface consistently showed a very low silver grain density and was underlain by large membranous vesicles, suggesting that new membrane derived from cytoplasmic precursors is inserted primarily in this location, at least during the later phase of cleavage. Radioiodinated membrane proteins and surface-attached carbon particles, which lie in the path of the future furrow, contract toward the animal pole in the initial stages of cleavage while markers in other regions do not. We suggest that the domain of heavily labeled membrane at the leading edge of the definitive furrow contains the labeled elements that are gathered at the animal pole during the initial surface contraction and that they include membrane anchors for the underlying contractile ring of microfilaments.

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Minestrini, Gianluca, Alyssa S. Harley i David M. Glover. "Localization of Pavarotti-KLP in Living Drosophila Embryos Suggests Roles in Reorganizing the Cortical Cytoskeleton during the Mitotic Cycle". Molecular Biology of the Cell 14, nr 10 (październik 2003): 4028–38. http://dx.doi.org/10.1091/mbc.e03-04-0214.

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Pav-KLP is the Drosophila member of the MKLP1 family essential for cytokinesis. In the syncytial blastoderm embryo, GFP-Pav-KLP cyclically associates with astral, spindle, and midzone microtubules and also to actomyosin pseudocleavage furrows. As the embryo cellularizes, GFP-Pav-KLP also localizes to the leading edge of the furrows that form cells. In mononucleate cells, nuclear localization of GFP-Pav-KLP is mediated through NLS elements in its C-terminal domain. Mutants in these elements that delocalize Pav-KLP to the cytoplasm in interphase do not affect cell division. In mitotic cells, one population of wild-type GFP-Pav-KLP associates with the spindle and concentrates in the midzone at anaphase B. A second is at the cell cortex on mitotic entry and later concentrates in the region of the cleavage furrow. An ATP binding mutant does not localize to the cortex and spindle midzone but accumulates on spindle pole microtubules to which actin is recruited. This leads either to failure of the cleavage furrow to form or later defects in which daughter cells remain connected by a microtubule bridge. Together, this suggests Pav-KLP transports elements of the actomyosin cytoskeleton to plus ends of astral microtubules in the equatorial region of the cell to permit cleavage ring formation.

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Niiya, Fumihiko, Xiaozhen Xie, Kyung S. Lee, Hiroki Inoue i Toru Miki. "Inhibition of Cyclin-dependent Kinase 1 Induces Cytokinesis without Chromosome Segregation in an ECT2 and MgcRacGAP-dependent Manner". Journal of Biological Chemistry 280, nr 43 (23.08.2005): 36502–9. http://dx.doi.org/10.1074/jbc.m508007200.

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Cleavage furrow formation marks the onset of cell division during early anaphase. The small GTPase RhoA and its regulators ECT2 and MgcRacGAP have been implicated in furrow ingression in mammalian cells, but the signaling upstream of these molecules remains unclear. We now show that the inhibition of cyclin-dependent kinase (Cdk)1 is sufficient to initiate cytokinesis. When mitotically synchronized cells were treated with the Cdk-specific inhibitor BMI-1026, the initiation of cytokinesis was induced precociously before chromosomal separation. Cytokinesis was also induced by the Cdk1-specific inhibitor purvalanol A but not by Cdk2/Cdk5- or Cdk4-specific inhibitors. Consistent with initiation of precocious cytokinesis by Cdk1 inhibition, introduction of anti-Cdk1 monoclonal antibody resulted in cells with aberrant nuclei. Depolymerization of mitotic spindles by nocodazole inhibited BMI-1026-induced precocious cytokinesis. However, in the presence of a low concentration of nocodazole, BMI-1026 induced excessive membrane blebbing, which appeared to be caused by formation of ectopic cleavage furrows. Depletion of ECT2 or MgcRacGAP by RNA interference abolished both of the phenotypes (precocious furrowing after nocodazole release and excessive blebbing in the presence of nocodazole). RNA interference of RhoA or expression of dominant-negative RhoA efficiently reduced both phenotypes. RhoA was localized at the cleavage furrow or at the necks of blebs. We propose that Cdk1 inactivation is sufficient to activate a signaling pathway leading to cytokinesis, which emanates from mitotic spindles and is regulated by ECT2, MgcRacGAP, and RhoA. Chemical induction of cytokinesis will be a valuable tool to study the initiation mechanism of cytokinesis.

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Chen, Qian, Hui Li i Arturo De Lozanne. "Contractile Ring-independent Localization of DdINCENP, a Protein Important for Spindle Stability and Cytokinesis". Molecular Biology of the Cell 17, nr 2 (luty 2006): 779–88. http://dx.doi.org/10.1091/mbc.e05-08-0704.

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Dictyostelium DdINCENP is a chromosomal passenger protein associated with centromeres, the spindle midzone, and poles during mitosis and the cleavage furrow during cytokinesis. Disruption of the single DdINCENP gene revealed important roles for this protein in mitosis and cytokinesis. DdINCENP null cells lack a robust spindle midzone and are hypersensitive to microtubule-depolymerizing drugs, suggesting that their spindles may not be stable. Furthermore DdCP224, a protein homologous to the microtubule-stabilizing protein TOGp/XMAP215, was absent from the spindle midzone of DdINCENP null cells. Overexpression of DdCP224 rescued the weak spindle midzone defect of DdINCENP null cells. Although not required for the localization of the myosin II contractile ring and subsequent formation of a cleavage furrow, DdINCENP is important for the abscission of daughter cells at the end of cytokinesis. Finally, we show that the localization of DdINCENP at the cleavage furrow is modulated by myosin II but it occurs by a mechanism different from that controlling the formation of the contractile ring.

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Mabuchi, Issei, Yukihisa Hamaguchi, Hirotaka Fujimoto, Narito Morii, Masanori Mishima i Shuh Narumiya. "A rho-like protein is involved in the organisation of the contractile ring in dividing sand dollar eggs". Zygote 1, nr 4 (listopad 1993): 325–31. http://dx.doi.org/10.1017/s0967199400001659.

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Sand dollar eggs were microinjected with botulinum C3 exoenzyme, an ADP-ribosyltransferase from Clostridium botulinum that specifically ADP-ribosylates and inactivates rho proteins. C3 exoenzyme microinjected during nuclear division interfered with subsequent cleavage furrow formation. No actin filaments were detected in the equatorial cortical layer of these eggs by rhodamine-phalloidin staining. When microinjected into furrowing eggs, C3 exoenzyme rapidly disrupted the contractile ring actin filaments and caused regression of the clevage furrows. C3 exoenzyme had no apparent effect on nuclear division, however, and multinucleated embryos developed from the microinjected eggs. By contrast, C3 exoenzyme did not affect the organisation of cortical actin filaments immediately after fertilisation. Only one protein (molecular weight 22000) was ADP-ribosylated by C3 exoenzyme in the isolated cleavage furrow. This protein co-migrated with ADP-ribosylated rhoA derived from human paltelets when analysed by two-dimensional gel electrophoresis. These results strongly suggest that a rho-like, small GTP-binding protein is selectively in the organisation and maintenance of the contractile ring.

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23

D'Avino, P. P., M. S. Savoian, L. Capalbo i D. M. Glover. "RacGAP50C is sufficient to signal cleavage furrow formation during cytokinesis". Journal of Cell Science 119, nr 21 (1.11.2006): 4402–8. http://dx.doi.org/10.1242/jcs.03210.

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KUOYEN, K., X. CHENGTANG i Z. KONGHUA. "Cleavage furrow formation of eggs observed with fluorescence pattern photobleaching". Cell Biology International Reports 12, nr 3 (marzec 1988): 175–87. http://dx.doi.org/10.1016/0309-1651(88)90094-x.

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Savoian, Matthew S., William C. Earnshaw, Alexey Khodjakov i Conly L. Rieder. "Cleavage Furrows Formed between Centrosomes Lacking an Intervening Spindle and Chromosomes Contain Microtubule Bundles, INCENP, and CHO1 but Not CENP-E". Molecular Biology of the Cell 10, nr 2 (luty 1999): 297–311. http://dx.doi.org/10.1091/mbc.10.2.297.

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PtK1 cells containing two independent mitotic spindles can cleave between neighboring centrosomes, in the absence of an intervening spindle, as well as at the spindle equators. We used same-cell video, immunofluorescence, and electron microscopy to compare the structure and composition of normal equatorial furrows with that of ectopic furrows formed between spindles. As in controls, ectopic furrows contained midbodies composed of microtubule bundles and an electron-opaque matrix. Despite the absence of an intervening spindle and chromosomes, the midbodies associated with ectopic furrows also contained the microtubule-bundling protein CHO1 and the chromosomal passenger protein INCENP. However, CENP-E, another passenger protein, was not found in ectopic furrows but was always present in controls. We also examined cells in which the ectopic furrow initiated but relaxed. Although relaxing furrows contained overlapping microtubules from opposing centrosomes, they lacked microtubule bundles as well as INCENP and CHO1. Together these data suggest that the mechanism defining the site of furrow formation during mitosis in vertebrates does not depend on the presence of underlying microtubule bundles and chromosomes or on the stable association of INCENP or CHO1. The data also suggest that the completion of cytokinesis requires the presence of microtubule bundles and specific proteins (e.g., INCENP, CHO1, etc.) that do not include CENP-E.

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26

Emoto, Kazuo, i Masato Umeda. "An Essential Role for a Membrane Lipid in Cytokinesis". Journal of Cell Biology 149, nr 6 (12.06.2000): 1215–24. http://dx.doi.org/10.1083/jcb.149.6.1215.

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Phosphatidylethanolamine (PE) is a major membrane phospholipid that is mainly localized in the inner leaflet of the plasma membrane. We previously demonstrated that PE was exposed on the cell surface of the cleavage furrow during cytokinesis. Immobilization of cell surface PE by a PE-binding peptide inhibited disassembly of the contractile ring components, including myosin II and radixin, resulting in formation of a long cytoplasmic bridge between the daughter cells. This blockade of contractile ring disassembly was reversed by removal of the surface-bound peptide, suggesting that the PE exposure plays a crucial role in cytokinesis. To further examine the role of PE in cytokinesis, we established a mutant cell line with a specific decrease in the cellular PE level. On the culture condition in which the cell surface PE level was significantly reduced, the mutant ceased cell growth in cytokinesis, and the contractile ring remained in the cleavage furrow. Addition of PE or ethanolamine, a precursor of PE synthesis, restored the cell surface PE on the cleavage furrow and normal cytokinesis. These findings provide the first evidence that PE is required for completion of cytokinesis in mammalian cells, and suggest that redistribution of PE on the cleavage furrow may contribute to regulation of contractile ring disassembly.

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27

Matheson, J., X. Yu, A. B. Fielding i G. W. Gould. "Membrane traffic in cytokinesis". Biochemical Society Transactions 33, nr 6 (26.10.2005): 1290–94. http://dx.doi.org/10.1042/bst0331290.

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A crucial facet of mammalian cell division is the separation of two daughter cells by a process known as cytokinesis. An early event in cytokinesis is the formation of an actomyosis contractile ring, which functions like a purse string in the constriction of the forming furrow between the cells. Far less well characterized are the membrane-trafficking steps which deliver new membrane to the cell surface during the plasma membrane expansion known to accompany furrow formation. It is now clearly established that the plasma membrane at the cleavage furrow of mammalian cells has a distinct lipid and protein composition from the rest of the plasma membrane. This may reflect a requirement for both increased surface area during furrowing and for the co-ordinated delivery of intracellular signalling or membrane re-modelling activities to the correct spatial coordinates during cleavage. In this review, we discuss recent work within the area of membrane traffic and cytokinesis.

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28

Geddis, Amy E., i Kenneth Kaushansky. "Aurora-B Kinase Translocates to the Midzone in Endomitotic Megakaryocytes." Blood 104, nr 11 (16.11.2004): 1263. http://dx.doi.org/10.1182/blood.v104.11.1263.1263.

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Abstract Megakaryocyte (MK) differentiation is marked by the development of progressive polyploidy, facilitating platelet production by the creation of a large cytoplasmic volume. MKs become polyploid through repeated cycles of endomitosis (EnM), in which mitosis is initiated but subsequently aborted in late anaphase with failure to complete karyokinesis and cytokinesis. However, the mechanisms underlying EnM remain poorly understood. Recent hypotheses explored in the literature have focused on the possible absence or mislocalization of the chromosomal passenger protein Aurora-B kinase, as it has a pivotal role in many aspects of cytokinesis. Along with the other passenger proteins, Aurora-B kinase transits from the centromeres of metaphase chromosomes to the bundled microtubules of the spindle midzone and overlying cortex between separating chromosomes in anaphase. The midzone and its associated proteins, are thought to be critical for determining the position of the cleavage furrow. One of these proteins, the kinesin MKLP-2, is required for the translocation of Aurora-B kinase to the midzone, where it co-localizes with the GTPase MgcRacGAP and stimulates its activity towards RhoA, potentially regulating actin dynamics at the cleavage furrow. We have previously demonstrated that several chromosomal passenger proteins including Aurora-B kinase are normally expressed and localized to centromeres in EnM MKs. In this work, we use deconvolution microscopy in primary murine and human MKs to extend those findings and demonstrate that EnM MKs form midzone structures that are characteristic of late anaphase; in addition, Aurora-B kinase is clearly present on the spindle midzone, as are MKLP-2 and MgcRacGAP. Although we found images suggestive of initial cleavage furrow formation with cortical localization of Aurora-B kinase in late phase cells, we were unable to demonstrate enhanced localization of actin or anillin to the furrow in EnM cells, despite their normal localization in diploid control cells. Therefore, many of the components of the central spindle are intact during MK EnM, but the formation of the cleavage furrow appears to be incomplete. These data add to our understanding of the possible mechanisms underlying EnM and offer an alternative hypothesis to that of failed expression or localization of the chromosomal passenger proteins. Ongoing studies will focus on the assembly and function of the cleavage furrow in this enigmatic process.

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29

Brill, J. A., G. R. Hime, M. Scharer-Schuksz i M. T. Fuller. "A phospholipid kinase regulates actin organization and intercellular bridge formation during germline cytokinesis". Development 127, nr 17 (1.09.2000): 3855–64. http://dx.doi.org/10.1242/dev.127.17.3855.

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The endgame of cytokinesis can follow one of two pathways depending on developmental context: resolution into separate cells or formation of a stable intercellular bridge. Here we show that the four wheel drive (fwd) gene of Drosophila melanogaster is required for intercellular bridge formation during cytokinesis in male meiosis. In fwd mutant males, contractile rings form and constrict in dividing spermatocytes, but cleavage furrows are unstable and daughter cells fuse together, producing multinucleate spermatids. fwd is shown to encode a phosphatidylinositol 4-kinase (PI 4-kinase), a member of a family of proteins that perform the first step in the synthesis of the key regulatory membrane phospholipid PIP2. Wild-type activity of the fwd PI 4-kinase is required for tyrosine phosphorylation in the cleavage furrow and for normal organization of actin filaments in the constricting contractile ring. Our results suggest a critical role for PI 4-kinases and phosphatidylinositol derivatives during the final stages of cytokinesis.

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30

Sawai, Tsuyoshi. "Effect of protein phosphatase inhibitors on cleavage furrow formation in newt eggs: Inhibition of normal furrow formation and concomitant induction of furrow-like dents". Development, Growth and Differentiation 39, nr 2 (kwiecień 1997): 235–42. http://dx.doi.org/10.1046/j.1440-169x.1997.t01-1-00012.x.

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31

García Cortés, Juan C., Mariona Ramos, Masako Osumi, Pilar Pérez i Juan Carlos Ribas. "The Cell Biology of Fission Yeast Septation". Microbiology and Molecular Biology Reviews 80, nr 3 (27.07.2016): 779–91. http://dx.doi.org/10.1128/mmbr.00013-16.

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SUMMARYIn animal cells, cytokinesis requires the formation of a cleavage furrow that divides the cell into two daughter cells. Furrow formation is achieved by constriction of an actomyosin ring that invaginates the plasma membrane. However, fungal cells contain a rigid extracellular cell wall surrounding the plasma membrane; thus, fungal cytokinesis also requires the formation of a special septum wall structure between the dividing cells. The septum biosynthesis must be strictly coordinated with the deposition of new plasma membrane material and actomyosin ring closure and must occur in such a way that no breach in the cell wall occurs at any time. Because of the high turgor pressure in the fungal cell, even a minor local defect might lead to cell lysis and death. Here we review our knowledge of the septum structure in the fission yeastSchizosaccharomyces pombeand of the recent advances in our understanding of the relationship between septum biosynthesis and actomyosin ring constriction and how the two collaborate to build a cross-walled septum able to support the high turgor pressure of the cell. In addition, we discuss the importance of the septum biosynthesis for the steady ingression of the cleavage furrow.

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32

Eckly, Anita, Harry Heijnen, Fabien Pertuy, Willie Geerts, Fabienne Proamer, Jean-Yves Rinckel, Catherine Léon, François Lanza i Christian Gachet. "Biogenesis of the demarcation membrane system (DMS) in megakaryocytes". Blood 123, nr 6 (6.02.2014): 921–30. http://dx.doi.org/10.1182/blood-2013-03-492330.

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Key Points Using state-of-the-art three-dimensional electron microscopy approaches, we show that the onset of the DMS formation is at the megakaryocyte plasma membrane. A pre-DMS structure is formed in the perinuclear region, through a PM invagination process that resembles cleavage furrow formation.

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33

D'Avino, P. P., M. S. Savoian i D. M. Glover. "Cleavage furrow formation and ingression during animal cytokinesis: a microtubule legacy". Journal of Cell Science 118, nr 8 (5.04.2005): 1549–58. http://dx.doi.org/10.1242/jcs.02335.

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IVANENKOV, V., A. MININ i V. MESHCHERYAKOV. "The effect of decrease of cortex tension on cleavage furrow formation". Cell Biology International Reports 14 (wrzesień 1990): 206. http://dx.doi.org/10.1016/0309-1651(90)90923-m.

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35

Müller-Taubenberger, Annette, Hellen C. Ishikawa-Ankerhold, Peter M. Kastner, Emmanuel Burghardt i Günther Gerisch. "The STE group kinase SepA controls cleavage furrow formation in Dictyostelium". Cell Motility and the Cytoskeleton 66, nr 11 (listopad 2009): 929–39. http://dx.doi.org/10.1002/cm.20386.

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Verma, Vikash, Alex Mogilner i Thomas J. Maresca. "Classical and Emerging Regulatory Mechanisms of Cytokinesis in Animal Cells". Biology 8, nr 3 (26.07.2019): 55. http://dx.doi.org/10.3390/biology8030055.

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The primary goal of cytokinesis is to produce two daughter cells, each having a full set of chromosomes. To achieve this, cells assemble a dynamic structure between segregated sister chromatids called the contractile ring, which is made up of filamentous actin, myosin-II, and other regulatory proteins. Constriction of the actomyosin ring generates a cleavage furrow that divides the cytoplasm to produce two daughter cells. Decades of research have identified key regulators and underlying molecular mechanisms; however, many fundamental questions remain unanswered and are still being actively investigated. This review summarizes the key findings, computational modeling, and recent advances in understanding of the molecular mechanisms that control the formation of the cleavage furrow and cytokinesis.

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37

Kwak, Eunice, Noel Gerald, Denis A. Larochelle, Kalpa K. Vithalani, Maria L. Niswonger, Melinda Maready i Arturo De Lozanne. "LvsA, a Protein Related to the Mouse Beige Protein, Is Required for Cytokinesis in Dictyostelium". Molecular Biology of the Cell 10, nr 12 (grudzień 1999): 4429–39. http://dx.doi.org/10.1091/mbc.10.12.4429.

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We isolated a Dictyostelium cytokinesis mutant with a defect in a novel locus called large volume sphere A (lvsA). lvsA mutants exhibit an unusual phenotype when attempting to undergo cytokinesis in suspension culture. Early in cytokinesis, they initiate furrow formation with concomitant myosin II localization at the cleavage furrow. However, the furrow is later disrupted by a bulge that forms in the middle of the cell. This bulge is bounded by furrows on both sides, which are often enriched in myosin II. The bulge can increase and decrease in size multiple times as the cell attempts to divide. Interestingly, this phenotype is similar to the cytokinesis failure of Dictyosteliumclathrin heavy-chain mutants. Furthermore, both cell lines cap ConA receptors but form only a C-shaped loose cap. Unlike clathrin mutants,lvsA mutants are not defective in endocytosis or development. The LvsA protein shares several domains in common with the molecules beige and Chediak–Higashi syndrome proteins that are important for lysosomal membrane traffic. Thus, on the basis of the sequence analysis of the LvsA protein and the phenotype of thelvsA mutants, we postulate that LvsA plays an important role in a membrane-processing pathway that is essential for cytokinesis.

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38

Sawai, Tsuyoshi. "Effect of Microtubular Poisons on Cleavage Furrow Formation and Induction of Furrow-like Dent in Amphibian Eggs". Development, Growth and Differentiation 34, nr 6 (grudzień 1992): 669–75. http://dx.doi.org/10.1111/j.1440-169x.1992.tb00035.x.

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Kunduri, Govind, Si-Hung Le, Valentina Baena, Nagampalli Vijaykrishna, Adam Harned, Kunio Nagashima, Daniel Blankenberg i in. "Delivery of ceramide phosphoethanolamine lipids to the cleavage furrow through the endocytic pathway is essential for male meiotic cytokinesis". PLOS Biology 20, nr 9 (28.09.2022): e3001599. http://dx.doi.org/10.1371/journal.pbio.3001599.

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Cell division, wherein 1 cell divides into 2 daughter cells, is fundamental to all living organisms. Cytokinesis, the final step in cell division, begins with the formation of an actomyosin contractile ring, positioned midway between the segregated chromosomes. Constriction of the ring with concomitant membrane deposition in a specified spatiotemporal manner generates a cleavage furrow that physically separates the cytoplasm. Unique lipids with specific biophysical properties have been shown to localize to intercellular bridges (also called midbody) connecting the 2 dividing cells; however, their biological roles and delivery mechanisms remain largely unknown. In this study, we show that ceramide phosphoethanolamine (CPE), the structural analog of sphingomyelin, has unique acyl chain anchors in Drosophila spermatocytes and is essential for meiotic cytokinesis. The head group of CPE is also important for spermatogenesis. We find that aberrant central spindle and contractile ring behavior but not mislocalization of phosphatidylinositol phosphates (PIPs) at the plasma membrane is responsible for the male meiotic cytokinesis defect in CPE-deficient animals. Further, we demonstrate the enrichment of CPE in multivesicular bodies marked by Rab7, which in turn localize to cleavage furrow. Volume electron microscopy analysis using correlative light and focused ion beam scanning electron microscopy shows that CPE-enriched Rab7 positive endosomes are juxtaposed on contractile ring material. Correlative light and transmission electron microscopy reveal Rab7 positive endosomes as a multivesicular body-like organelle that releases its intraluminal vesicles in the vicinity of ingressing furrows. Genetic ablation of Rab7 or Rab35 or expression of dominant negative Rab11 results in significant meiotic cytokinesis defects. Further, we show that Rab11 function is required for localization of CPE positive endosomes to the cleavage furrow. Our results imply that endosomal delivery of CPE to ingressing membranes is crucial for meiotic cytokinesis.

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40

Foe, V. E., C. M. Field i G. M. Odell. "Microtubules and mitotic cycle phase modulate spatiotemporal distributions of F-actin and myosin II in Drosophila syncytial blastoderm embryos". Development 127, nr 9 (1.05.2000): 1767–87. http://dx.doi.org/10.1242/dev.127.9.1767.

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We studied cyclic reorganizations of filamentous actin, myosin II and microtubules in syncytial Drosophila blastoderms using drug treatments, time-lapse movies and laser scanning confocal microscopy of fixed stained embryos (including multiprobe three-dimensional reconstructions). Our observations imply interactions between microtubules and the actomyosin cytoskeleton. They provide evidence that filamentous actin and cytoplasmic myosin II are transported along microtubules towards microtubule plus ends, with actin and myosin exhibiting different affinities for the cell's cortex. Our studies further reveal that cell cycle phase modulates the amounts of both polymerized actin and myosin II associated with the cortex. We analogize pseudocleavage furrow formation in the Drosophila blastoderm with how the mitotic apparatus positions the cleavage furrow for standard cytokinesis, and relate our findings to polar relaxation/global contraction mechanisms for furrow formation.

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41

Robinson, Douglas N., Tracy A. Smith-Leiker, Nicholas S. Sokol, Andrew M. Hudson i Lynn Cooley. "Formation of the Drosophila Ovarian Ring Canal Inner Rim Depends on cheerio". Genetics 145, nr 4 (1.04.1997): 1063–72. http://dx.doi.org/10.1093/genetics/145.4.1063.

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In Drosophila oogenesis, the development of a mature oocyte depends on having properly developed ring canals that allow cytoplasm transport from the nurse cells to the oocyte. Ring canal assembly is a step-wise process that transforms an arrested cleavage furrow into a stable intercellular bridge by the addition of several proteins. Here we describe a new gene we named cheerio that provides a critical function for ring canal assembly. Mutants in cheerio fail to localize ring canal inner rim proteins including filamentous actin, the ring canal-associated products from the hu-li tai shao (hts) gene, and kelch. Since hts and kelch are present but unlocalized in cheerio mutant cells, cheerio is likely to function upstream from each of them. Examination of mutants in cheerio places it in the pathway of ring canal assembly between cleavage furrow arrest and localization of hts and actin filaments. Furthermore, this mutant reveals that the inner rim cytoskeleton is required for expansion of the ring canal opening and for plasma membrane stabilization.

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Bastos, Ricardo Nunes, i Francis A. Barr. "Plk1 negatively regulates Cep55 recruitment to the midbody to ensure orderly abscission". Journal of Cell Biology 191, nr 4 (15.11.2010): 751–60. http://dx.doi.org/10.1083/jcb.201008108.

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Cytokinesis requires a membrane-remodeling and fission event termed abscission that occurs after chromosome segregation, cleavage furrow formation, and contraction have completed. In this study, we show how abscission factor recruitment is controlled by the Polo-like kinase 1 (Plk1). At the metaphase–anaphase transition, Plk1 initiates cleavage furrow formation and is then progressively degraded during mitotic exit. During this period, Plk1 phosphorylates the abscission factor Cep55 in trans and prevents its untimely recruitment to the anaphase spindle. A Plk1 phosphorylation site mutant of Cep55 is prematurely recruited to the anaphase spindle and fails to support abscission. Endogenous Cep55 behaves similarly after Plk1 inhibition by the drugs BI2536 or GW842862. Only once Plk1 is degraded can Cep55 target to the midbody and promote abscission. Blocking Plk1 degradation leads to elevated levels of Plk1 at the midbody and the failure of Cep55 recruitment. Thus, Plk1 activity negatively regulates Cep55 to ensure orderly abscission factor recruitment and ensures that this occurs only once cell contraction has completed.

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43

Liu, Changyu, Dapeng Li, Bin Lu i Tiezhu Zhao. "Cleavage Furrow Formation for Avascular Tumor Growth based on Finite Element Modeling". International Journal of Multimedia and Ubiquitous Engineering 10, nr 3 (31.03.2015): 219–30. http://dx.doi.org/10.14257/ijmue.2015.10.3.21.

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Dundon, Samantha E. R., i Thomas D. Pollard. "Microtubule nucleation promoters Mto1 and Mto2 regulate cytokinesis in fission yeast". Molecular Biology of the Cell 31, nr 17 (1.08.2020): 1846–56. http://dx.doi.org/10.1091/mbc.e19-12-0686.

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Dundon and Pollard show that compromising the Mto1 or Mto2 regulators of the fission yeast γ-tubulin complex reduces or eliminates astral microtubules, exaggerates the effects of a D277N substitution in β-glucan synthase 1 (Cps1/Bgs1) on the rate of cytokinetic furrow formation, and increases Rho1-GTP at the cleavage site.

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45

Kanazawa, Takayuki, Sachiko Nakamura, Michiko Momoi, Toshiyuki Yamaji, Hiromu Takematsu, Hajime Yano, Hisataka Sabe, Akitsugu Yamamoto, Toshisuke Kawasaki i Yasunori Kozutsumi. "Inhibition of Cytokinesis by a Lipid Metabolite, Psychosine". Journal of Cell Biology 149, nr 4 (15.05.2000): 943–50. http://dx.doi.org/10.1083/jcb.149.4.943.

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Although a number of cellular components of cytokinesis have been identified, little is known about the detailed mechanisms underlying this process. Here, we report that the lipid metabolite psychosine (galactosylsphingosine), derived from galactosylceramide, induced formation of multinuclear cells from a variety of nonadherent and adherent cells due to inhibition of cytokinesis. When psychosine was added to the human myelomonocyte cell line U937, which was the most sensitive among the cell lines tested, cleavage furrow formed either incompletely or almost completely. However, abnormal contractile movement was detected in which the cellular contents of one of the hemispheres of the contracting cell were transferred into its counterpart. Finally, the cleavage furrow disappeared and cytokinesis was reversed. Psychosine treatment also induced giant clots of actin filaments in the cells that probably consisted of small vacuoles with filamentous structures, suggesting that psychosine affected actin reorganization. These observations could account for the formation of multinuclear globoid cells in the brains of patients with globoid cell leukodystrophy, a neurological disorder characterized by the accumulation of psychosine due to galactosylceramidase deficiency.

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46

Sawai, Tsuyoshi. "Evidences for Direct Involvement of Microtubules in Cleavage Furrow Formation in Newt Eggs". Zoological Science 15, nr 1 (styczeń 1998): 51–56. http://dx.doi.org/10.2108/zsj.15.51.

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47

Kubota, Tomoyuki, i Masahiko Sakamoto. "Furrow Formation in the Vegetal Hemisphere of Xenopus Eggs. (Xenopus eggs/ cleavage/microtubules)". Development, Growth and Differentiation 35, nr 4 (sierpień 1993): 403–7. http://dx.doi.org/10.1111/j.1440-169x.1993.00403.x.

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48

Chalamalasetty, R. B., S. Hummer, E. A. Nigg i H. H. W. Sillje. "Influence of human Ect2 depletion and overexpression on cleavage furrow formation and abscission". Journal of Cell Science 119, nr 14 (27.06.2006): 3008–19. http://dx.doi.org/10.1242/jcs.03032.

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49

Andreassen, P. R., D. K. Palmer, M. H. Wener i R. L. Margolis. "Telophase disc: a new mammalian mitotic organelle that bisects telophase cells with a possible function in cytokinesis". Journal of Cell Science 99, nr 3 (1.07.1991): 523–34. http://dx.doi.org/10.1242/jcs.99.3.523.

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We have discovered a novel mitosis-specific human autoantigen that arises at the centromeres of prophase chromosomes, but ultimately participates in formation of an organelle that bisects the cell at late anaphase and during telophase. The organelle, discernible as a three-dimensional disc by confocal microscopy, encompasses the entire midzone diameter, and its distribution survives disassembly of interpolar microtubules by cold temperature treatment and detergent lysis of cells. Cytokinetic furrow contraction proceeds normally in dihydrocytochalasin B (DCB)-treated cells, and antigen distribution in the furrow is unaltered. In DCB, the furrow retracts in early interphase, coincident with loss of normal membrane association with the disc, resulting in the formation of binucleate cells. The midzone disc in both drug-treated and normal cells is present at the correct time and position to play a central role in cytokinesis. By immunocytochemistry, the disc appears to contain myosin but not actin. The position of the disc and the possible presence of myosin suggest that cytokinesis may involve the interaction of the disc organelle with actin in the cell cortex to produce cleavage in mammalian cells.

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50

Sechi, Stefano, Anna Frappaolo, Roberta Fraschini, Luisa Capalbo, Marco Gottardo, Giorgio Belloni, David M. Glover, Alan Wainman i Maria Grazia Giansanti. "Rab1 interacts with GOLPH3 and controls Golgi structure and contractile ring constriction during cytokinesis in Drosophila melanogaster". Open Biology 7, nr 1 (styczeń 2017): 160257. http://dx.doi.org/10.1098/rsob.160257.

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Cytokinesis requires a tight coordination between actomyosin ring constriction and new membrane addition along the ingressing cleavage furrow. However, the molecular mechanisms underlying vesicle trafficking to the equatorial site and how this process is coupled with the dynamics of the contractile apparatus are poorly defined. Here we provide evidence for the requirement of Rab1 during cleavage furrow ingression in cytokinesis. We demonstrate that the gene omelette ( omt ) encodes the Drosophila orthologue of human Rab1 and is required for successful cytokinesis in both mitotic and meiotic dividing cells of Drosophila melanogaster . We show that Rab1 protein colocalizes with the conserved oligomeric Golgi (COG) complex Cog7 subunit and the phosphatidylinositol 4-phosphate effector GOLPH3 at the Golgi stacks. Analysis by transmission electron microscopy and 3D-SIM super-resolution microscopy reveals loss of normal Golgi architecture in omt mutant spermatocytes indicating a role for Rab1 in Golgi formation. In dividing cells, Rab1 enables stabilization and contraction of actomyosin rings. We further demonstrate that GTP-bound Rab1 directly interacts with GOLPH3 and controls its localization at the Golgi and at the cleavage site . We propose that Rab1, by associating with GOLPH3, controls membrane trafficking and contractile ring constriction during cytokinesis.

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