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Not to be confused with Meiosis, Miosis, Myositis, or Myosotis.
Mitosis in an animal cell.
Mitosis divides the chromosomes in a cell nucleus.
Onion (Allium) cells in different phases of the cell cycle enlarged 800 diameters.
a. non-dividing cells
b. nuclei preparing for division (spireme-stage)
c. dividing cells showing mitotic figures
e. pair of daughter-cells shortly after division

Mitosis is a part of the cell cycle in which chromosomes in a cell nucleus are separated into two identical sets of chromosomes, each in its own nucleus. In general, mitosis (division of the nucleus) is often followed by cytokinesis, which divides the cytoplasm, organelles and cell membrane into two new cells containing roughly equal shares of these cellular components.[1] Mitosis and cytokinesis together define the mitotic (M) phase of an animal cell cycle—the division of the mother cell into two daughter cells, genetically identical to each other and to their parent cell.

The process of mitosis is divided into stages corresponding to the completion of one set of activities and the start of the next. These stages are prophase, prometaphase, metaphase, anaphase, and telophase. During mitosis, the chromosomes, which have already duplicated, condense and attach to fibers that pull one copy of each chromosome to opposite sides of the cell. The result is two genetically identical daughter nuclei. The cell may then divide by cytokinesis to produce two daughter cells.[2] Producing three or more daughter cells instead of normal two is a mitotic error called tripolar mitosis or multipolar mitosis (direct cell triplication / multiplication).[3] Other errors during mitosis can induce apoptosis (programmed cell death) or cause mutations. Certain types of cancer can arise from such mutations.[4]

Mitosis occurs only in eukaryotic cells and the process varies in different organisms.[5] For example, animals undergo an "open" mitosis, where the nuclear envelope breaks down before the chromosomes separate, while fungi undergo a "closed" mitosis, where chromosomes divide within an intact cell nucleus.[6] Furthermore, most animal cells undergo a shape change, known as mitotic cell rounding, to adopt a near spherical morphology at the start of mitosis. Prokaryotic cells, which lack a nucleus, divide by a different process called binary fission.


German zoologist Otto Bütschli was one of the first researchers who might have claimed the discovery of the process presently known as "mitosis",[7] a term coined by Walther Flemming in 1882.[8]

Mitosis was discovered in frog, rabbit, and cat cornea cells in 1873 and described for the first time by the Polish histologist Wacław Mayzel in 1875.[9][10] The term is derived from the Greek word μίτος mitos "warp thread".[11][12]

Overview of mitosis[edit]

Time-lapse video of mitosis in a Drosophila melanogaster embryo.
Types of mitosis

The primary result of mitosis and cytokinesis is the transfer of a parent cell's genome into two daughter cells. The genome is composed of a number of chromosomes—complexes of tightly coiled DNA that contain genetic information vital for proper cell function. Because each resultant daughter cell should be genetically identical to the parent cell, the parent cell must make a copy of each chromosome before mitosis. This occurs during the S phase of interphase.[13] Chromosome duplication results in two identical sister chromatids bound together by cohesin proteins at the centromere.

When mitosis begins, the chromosomes condense and become visible. In some eukaryotes, for example animals, the nuclear envelope, which segregates the DNA from the cytoplasm, disintegrates into small vesicles. The nucleolus, which makes ribosomes in the cell, also disappears. Microtubules project from opposite ends of the cell, attach to the centromeres, and align the chromosomes centrally within the cell. The microtubules then contract to pull the sister chromatids of each chromosome apart.[14] Sister chromatids at this point are called daughter chromosomes. As the cell elongates, corresponding daughter chromosomes are pulled toward opposite ends of the cell. A new nuclear envelope forms around the separated daughter chromosomes.

As mitosis concludes, the cell may begin cytokinesis. In animal cells, a cell membrane pinches inward between the two developing nuclei to produce two new cells. In plant cells, a cell plate forms between the two nuclei.Cytokinesis does not always occur; coenocytic (a type of multinucleate condition) cells undergo mitosis without cytokinesis.

Phases of cell cycle and mitosis[edit]

The cell cycle


Main article: Interphase

The mitotic phase is a relatively short period of the cell cycle. It alternates with the much longer interphase, where the cell prepares itself for the process of cell division. Interphase is divided into three phases: G1 (first gap), S (synthesis), and G2 (second gap). During all three phases, the cell grows by producing proteins and cytoplasmic organelles. However, chromosomes are replicated only during the S phase. Thus, a cell grows (G1), continues to grow as it duplicates its chromosomes (S), grows more and prepares for mitosis (G2), and finally divides (M) before restarting the cycle.[13] All these phases in the cell cycle are highly regulated by cyclins, cyclin-dependent kinases, and other cell cycle proteins. The phases follow one another in strict order and there are "checkpoints" that give the cell cues to proceed from one phase to another. Cells may also temporarily or permanently leave the cell cycle and enter G0 phase to stop dividing. This can occur when cells become overcrowded (density-dependent inhibition) or when they differentiate to carry out specific functions for the organism, as is the case for human heart muscle cells and neurons. Some G0 cells have the ability to re-enter the cell cycle.

Preprophase (plant cells)[edit]

Main article: Preprophase


Phases of mitosis
Prometaphase: The nuclear envelope disintegrates, and microtubules have invaded the nuclear space. These microtubules can attach to kinetochores or they can interact with opposing microtubules. 
Metaphase: The chromosomes align at the metaphase plate. 
Anaphase: The chromosomes split and the kinetochore microtubules shorten. 
Telophase: The decondensing chromosomes are surrounded by newly formed nuclear envelopes. Cytokinesis has already begun; the pinched area is known as the cleavage furrow


Main article: Prophase

During prophase, which occurs after G2 interphase, the cell prepares to divide by tightly condensing its chromosomes and initiating mitotic spindle formation. During interphase, the genetic material in the nucleus consists of loosely packed chromatin. At the onset of prophase, chromatin fibers condense into discrete chromosomes that are typically visible at high magnification through a light microscope. Gene transcription ceases during prophase and does not resume until late anaphase to early G1 phase.[17][18][19] The nucleolus also disappears during early prophase.[20]


Close to the nucleus of animal cells are structures called centrosomes, consisting of a pair of centrioles surrounded by a loose collection of proteins. The centrosome is the coordinating center for the cell's microtubules. A cell inherits a single centrosome at cell division, which is duplicated by the cell before a new round of mitosis begins, giving a pair of centrosomes. The two centrosomes polymerize tubulin to help form a microtubule spindle apparatus. Motor proteins then push the centrosomes along these microtubules to opposite sides of the cell. Although centrosomes help organize microtubule assembly, they are not essential for the formation of the spindle apparatus, since they are absent from plants,[15] and are not absolutely required for animal cell mitosis.[21]


Main article: Prometaphase

At the beginning of prometaphase in animal cells, phosphorylation of nuclear lamins causes the nuclear envelope to disintegrate into small membrane vesicles. As this happens, microtubules invade the nuclear space. This is called open mitosis, and it occurs in some multicellular organisms. Fungi and some protists, such as algae or trichomonads, undergo a variation called closed mitosis where the spindle forms inside the nucleus, or the microtubules penetrate the intact nuclear envelope.[22][23]

In late prometaphase, kinetochore microtubules begin to search for and attach to chromosomal kinetochores.[24] A kinetochore is a proteinaceous microtubule-binding structure that forms on the chromosomal centromere during late prophase.[24][25] A number of polar microtubules find and interact with corresponding polar microtubules from the opposite centrosome to form the mitotic spindle.[26] Although the kinetochore structure and function are not fully understood, it is known that it contains some form of molecular motor.[27] When a microtubule connects with the kinetochore, the motor activates, using energy from ATP to "crawl" up the tube toward the originating centrosome. This motor activity, coupled with polymerisation and depolymerisation of microtubules, provides the pulling force necessary to later separate the chromosome's two chromatids.[27]


Main article: Metaphase

After the microtubules have located and attached to the kinetochores in prometaphase, the two centrosomes begin pulling the chromosomes towards opposite ends of the cell. The resulting tension causes the chromosomes to align along the metaphase plate or equatorial plane, an imaginary line that is centrally located between the two centrosomes (at approximately the midline of the cell).[26] To ensure equitable distribution of chromosomes at the end of mitosis, the metaphase checkpoint guarantees that kinetochores are properly attached to the mitotic spindle and that the chromosomes are aligned along the metaphase plate.[28] If the cell successfully passes through the metaphase checkpoint, it proceeds to anaphase.


Main article: Anaphase

During anaphase A, the cohesins that bind sister chromatids together are cleaved, forming two identical daughter chromosomes.[29] Shortening of the kinetochore microtubules pulls the newly formed daughter chromosomes to opposite ends of the cell. During anaphase B, polar microtubules push against each other, causing the cell to elongate.[30] In most animal cells, anaphase A precedes anaphase B, but some vertebrate egg cells demonstrate the opposite order of events.[29]


Main article: Telophase

Telophase (from the Greek word τελος meaning "end") is a reversal of prophase and prometaphase events. At telophase, the polar microtubules continue to lengthen, elongating the cell even more. If the nuclear envelope has broken down, a new nuclear envelope forms using the membrane vesicles of the parent cell's old nuclear envelope. The new envelope forms around each set of separated daughter chromosomes (though the membrane does not enclose the centrosomes) and the nucleolus reappears. Both sets of chromosomes, now surrounded by new nuclear membrane, begin to "relax" or decondense. Mitosis is complete. Each daughter nucleus has an identical set of chromosomes. Cell division may or may not occur at this time depending on the organism.


Cilliate undergoing cytokinesis, with the cleavage furrow being clearly visible
Main article: Cytokinesis

Cytokinesis is not a phase of mitosis but rather a separate process, necessary for completing cell division. In animal cells, a cleavage furrow (pinch) containing a contractile ring develops where the metaphase plate used to be, pinching off the separated nuclei.[31] In both animal and plant cells, cell division is also driven by vesicles derived from the Golgi apparatus, which move along microtubules to the middle of the cell.[32] In plants, this structure coalesces into a cell plate at the center of the phragmoplast and develops into a cell wall, separating the two nuclei. The phragmoplast is a microtubule structure typical for higher plants, whereas some green algae use a phycoplast microtubule array during cytokinesis.[33] Each daughter cell has a complete copy of the genome of its parent cell. The end of cytokinesis marks the end of the M-phase.

There are many cells where mitosis and cytokinesis occur separately, forming single cells with multiple nuclei. The most notable occurrence of this is among the fungi, slime molds, and coenocytic algae, but the phenomenon is found in various other organisms. Even in animals, cytokinesis and mitosis may occur independently, for instance during certain stages of fruit fly embryonic development.[34]



Mitosis occurs in the following circumstances:

Development and growth
The number of cells within an organism increases by mitosis. This is the basis of the development of a multicellular body from a single cell, i.e., zygote and also the basis of the growth of a multicellular body.
Cell replacement
In some parts of body, e.g. skin and digestive tract, cells are constantly sloughed off and replaced by new ones. New cells are formed by mitosis and so are exact copies of the cells being replaced. In like manner, red blood cells have short lifespan (only about 4 months) and new RBCs are formed by mitosis.
Asexual reproduction

Cell shape changes during mitosis[edit]

Cell shape changes through mitosis for a typical animal cell cultured on a flat surface. The cell undergoes mitotic cell rounding during spindle assembly and then divides via cytokinesis. The actomyosin cortex is depicted in red, DNA/chromosomes purple, microtubules green, and membrane and retraction fibers in black. Rounding also occurs in live tissue, as described in the text.
Main article: Mitotic cell rounding

In animal tissue, most cells round up to a near-spherical shape during mitosis.[35][36][37] In epithelia and epidermis, an efficient rounding process is correlated with proper mitotic spindle alignment and subsequent correct positioning of daughter cells.[36][37][38][39] Moreover, researchers have found that if rounding is heavily suppressed it may result in spindle defects, primarily pole splitting and failure to efficiently capture chromosomes.[40] Therefore, mitotic cell rounding is thought to play a protective role in ensuring accurate mitosis.[39][41]

Rounding forces are driven by reorganization of F-actin and myosin (actomyosin) into a contractile homogeneous cell cortex that 1) rigidifies the cell periphery[41][42][43] and 2) facilitates generation of intracellular hydrostatic pressure (up to 10 fold higher than interphase).[44][45][46] The generation of intracellular pressure is particularly critical under confinement, such as would be important in a tissue scenario, where outward forces must be produced to round up against surrounding cells and/or the extracellular matrix. Generation of pressure is dependent on formin-mediated F-actin nucleation[46] and Rho kinase (ROCK)-mediated myosin II contraction,[42][44][46] both of which are governed upstream by signaling pathways RhoA and ECT2[42][43] through the activity of Cdk1.[46] Due to its importance in mitosis, the molecular components and dynamics of the mitotic actomyosin cortex is an area of active research.

Errors and variations of mitosis[edit]

An abnormal (tripolar) mitosis (12 o'clock position) in a precancerous lesion of the stomach (H&E stain)

Errors can occur during mitosis, especially during early embryonic development in humans.[47] Mitotic errors can create aneuploid cells that have too few or too many of one or more chromosomes, a condition associated with cancer.[48] Early human embryos, cancer cells, infected or intoxicated cells can also suffer from pathological division into three or more daughter cells (tripolar or multipolar mitosis), resulting in severe errors in their chromosomal complements.[49]

In nondisjunction, sister chromatids fail to separate during anaphase.[50] One daughter cell receives both sister chromatids from the nondisjoining chromosome and the other cell receives none. As a result, the former cell gets three copies of the chromosome, a condition known as trisomy, and the latter will have only one copy, a condition known as monosomy. On occasion, when cells experience nondisjunction, they fail to complete cytokinesis and retain both nuclei in one cell, resulting in binucleated cells.[51]

Anaphase lag occurs when the movement of one chromatid is impeded during anaphase.[50] This may be caused by a failure of the mitotic spindle to properly attach to the chromosome. The lagging chromatid is excluded from both nuclei and is lost. Therefore, one of the daughter cells will be monosomic for that chromosome.

Endoreduplication (or endoreplication) occurs when chromosomes duplicate but the cell does not subsequently divide. This results in polyploid cells or, if the chromosomes duplicates repeatedly, polytene chromosomes.[50][52] Endoreduplication is found in many species and appears to be a normal part of development.[52] Endomitosis is a variant of endoreduplication in which cells replicate their chromosomes during S phase and enter, but prematurely terminate, mitosis. Instead of being divided into two new daughter nuclei, the replicated chromosomes are retained within the original nucleus.[34][53] The cells then re-enter G1 and S phase and replicate their chromosomes again.[53] This may occur multiple times, increasing the chromosome number with each round of replication and endomitosis. Platelet-producing megakaryocytes go through endomitosis during cell differentiation.[54][55]

Timeline in pictures[edit]

Mitotic cells can be visualized microscopically by staining them with fluorescent antibodies and dyes.

Early prophase: Nonkinetochore microtubules, shown as green strands, have established a matrix around the degrading nucleus, in blue. The green nodules are the centrosomes. 
Early prometaphase: The nuclear envelope has just disintegrated, allowing the microtubules to quickly interact with the kinetochores on the chromosomes, which have just condensed. 
Anaphase: Lengthening nonkinetochore microtubules push the two sets of chromosomes further apart. 
Telophase: Reversal of prophase and prometaphase events. 

See also[edit]


  1. ^ Carter, J. Stein (2014-01-14). "Mitosis". 
  2. ^ Maton, A.; Hopkins, J. J.; LaHart, S; Quon Warner, D.; Wright, M.; Jill, D. (1997). Cells: Building Blocks of Life. New Jersey: Prentice Hall. pp. 70–4. ISBN 0-13-423476-6. 
  3. ^ Kalatova, B.; Jesenska, R.; Hlinka, D.; Dudas, M. (2015). "Tripolar mitosis in human cells and embryos: Occurrence, pathophysiology and medical implications". Acta Histochemica 117 (1): 111–125. doi:10.1016/j.acthis.2014.11.009. PMID 25554607. 
  4. ^ Kops, G. J.; Weaver, B. A.; Cleveland, D. W. (October 2005). "On the road to cancer: Aneuploidy and the mitotic checkpoint". Nature Reviews Cancer 5 (10): 773–785. doi:10.1038/nrc1714. PMID 16195750. 
  5. ^ Raikov, IB (1994). "The diversity of forms of mitosis in protozoa: A comparative review". European Journal of Protistology 30 (3): 253–69. doi:10.1016/S0932-4739(11)80072-6. 
  6. ^ De Souza, C. P.; Osmani, S. A. (2007). "Mitosis, Not Just Open or Closed". Eukaryotic Cell 6 (9): 1521–7. doi:10.1128/EC.00178-07. PMC 2043359. PMID 17660363. 
  7. ^ Fokin, S. I. (2013). Otto Bütschli (1848–1920): Where we will genuflect? Protistology, 8 (1), 22–35.
  8. ^ Sharp, L. W. (1921). Introduction To Cytology. New York: McGraw Hill Book Company Inc. p. 143. 
  9. ^ Janusz Komender (2008). "Kilka słów o doktorze Wacławie Mayzlu i jego odkryciu" [A few words about Dr. Wenceslaus Mayzlu and its discovery] (PDF). Postępy Biologii Komórki (in Polish) (Polskie Towarzystwo Anatomiczne, Polskie Towarzystwo Biologii Komórki) 35 (3): 405–407. 
  11. ^ "mitosis". Online Etymology Dictionary. 
  12. ^ μίτος. Liddell, Henry George; Scott, Robert; A Greek–English Lexicon at the Perseus Project
  13. ^ a b Blow, J.; Tanaka, T. (2005). "The chromosome cycle: coordinating replication and segregation: Second in the cycles review series". EMBO Reports 6 (11): 1028–34. doi:10.1038/sj.embor.7400557. PMC 1371039. PMID 16264427. 
  14. ^ Zhou, J.; Yao, J.; Joshi, H. (2002). "Attachment and tension in the spindle assembly checkpoint". Journal of Cell Science 115 (Pt 18): 3547–55. doi:10.1242/jcs.00029. PMID 12186941. 
  15. ^ a b Lloyd, C.; Chan, J. (2006). "Not so divided: the common basis of plant and animal cell division". Nature reviews. Molecular cell biology 7 (2): 147–52. doi:10.1038/nrm1831. PMID 16493420. 
  16. ^ Raven et al., 2005, pp. 58–67.
  17. ^ Prasanth, K. V.; Sacco-Bubulya, P. A.; Prasanth, S. G.; Spector, D. L. (2003). "Sequential entry of components of the gene expression machinery into daughter nuclei". Molecular Biology of the Cell 14 (3): 1043–57. doi:10.1091/mbc.E02-10-0669. PMC 151578. PMID 12631722. 
  18. ^ Kadauke, S; Blobel, G. A. (2013). "Mitotic bookmarking by transcription factors". Epigenetics & Chromatin 6 (1): 6. doi:10.1186/1756-8935-6-6. PMC 3621617. PMID 23547918. 
  19. ^ Prescott, D. M.; Bender, M. A. (1962). "Synthesis of RNA and protein during mitosis in mammalian tissue culture cells". Experimental cell research 26: 260–8. PMID 14488623. 
  20. ^ Olson, Mark O. J. (2011). The Nucleolus. Volume 15 of Protein Reviews. Berlin: Springer Science & Business Media. p. 15. ISBN 9781461405146. 
  21. ^ Basto, R.; Lau, J.; Vinogradova, T.; Gardiol, A.; Woods, G.; Khodjakov, A.; Raff, W. (June 2006). "Flies without centrioles". Cell 125 (7): 1375–1386. doi:10.1016/j.cell.2006.05.025. PMID 16814722. 
  22. ^ Heywood, P. (1978). "Ultrastructure of mitosis in the chloromonadophycean alga Vacuolaria virescens". Journal of Cell Science 31: 37–51. PMID 670329. 
  23. ^ Ribeiro, K.; Pereira-Neves, A; Benchimol, M. (2002). "The mitotic spindle and associated membranes in the closed mitosis of trichomonads". Biology of the Cell 94 (3): 157–72. doi:10.1016/S0248-4900(02)01191-7. PMID 12206655. 
  24. ^ a b Chan, G.; Liu, S.; Yen, T. (2005). "Kinetochore structure and function". Trends in Cell Biology 15 (11): 589–98. doi:10.1016/j.tcb.2005.09.010. PMID 16214339. 
  25. ^ Cheeseman, Iain M.; Desai, Arshad (January 2008). "Molecular architecture of the kinetochore–microtubule interface". Nature Reviews Molecular Cell Biology 9 (1): 33–46. doi:10.1038/nrm2310. PMID 18097444. 
  26. ^ a b Winey, M.; Mamay, C.; O'Toole, E.; Mastronarde, D.; Giddings, T.; McDonald, K.; McIntosh, J. (1995). "Three-dimensional ultrastructural analysis of the Saccharomyces cerevisiae mitotic spindle". Journal of Cell Biology 129 (6): 1601–15. doi:10.1083/jcb.129.6.1601. PMC 2291174. PMID 7790357. 
  27. ^ a b Maiato, H.; DeLuca, J.; Salmon, E.; Earnshaw, W. (2004). "The dynamic kinetochore-microtubule interface". Journal of Cell Science 117 (Pt 23): 5461–77. doi:10.1242/jcs.01536. PMID 15509863. 
  28. ^ Chan, G.; Yen, T. (2003). "The mitotic checkpoint: a signaling pathway that allows a single unattached kinetochore to inhibit mitotic exit". Progress in Cell Cycle Research 5: 431–9. PMID 14593737. 
  29. ^ a b FitzHarris, G. (March 2012). "Anaphase B precedes anaphase A in the mouse egg". Current Biology 22 (5): 437–444. doi:10.1016/j.cub.2012.01.041. PMID 22342753. open access publication - free to read
  30. ^ Miller, K. R. g (2000). "Anaphase". Biology (5 ed.). Pearson Prentice Hall. pp. 169–70. ISBN 978-0-13-436265-6. 
  32. ^ Albertson, R.; Riggs, B.; Sullivan, W. (2005). "Membrane traffic: a driving force in cytokinesis". Trends in Cell Biology 15 (2): 92–101. doi:10.1016/j.tcb.2004.12.008. PMID 15695096. 
  34. ^ a b Lilly, .M; Duronio, R. (2005). "New insights into cell cycle control from the Drosophila endocycle". Oncogene 24 (17): 2765–75. doi:10.1038/sj.onc.1208610. PMID 15838513. 
  35. ^ Sauer, F. C. (1935). "Mitosis in the neural tube". Journal of Comparative Neurology 62 (2): 377-405. doi:10.1002/cne.900620207. 
  36. ^ a b Meyer, E. J. (2011). "Interkinetic Nuclear Migration Is a Broadly Conserved Feature of Cell Division in Pseudostratified Epithelia". Current Biology 21 (6): 485–491. doi:10.1016/j.cub.2011.02.002. PMID 21376598. 
  37. ^ a b Luxenburg, Chen; et al. (2011). "Developmental roles for Srf, cortical cytoskeleton and cell shape in epidermal spindle orientation". Nature Cell Biology 13 (3): 203–U51. doi:10.1038/Ncb2163. PMID 21336301. 
  38. ^ Nakajima, Yu-Ichiro; Meyer, Emily J; Kroesen, Amanda; McKinney, Sean A; Gibson, Matthew C (2013). "Epithelial junctions maintain tissue architecture by directing planar spindle orientation". Nature 500 (7462): 359–362. doi:10.1038/nature12335. PMID 23873041. 
  39. ^ a b Cadart, C.; Zlotek-Zlotkiewicz, E.; Le Berre, M.; Piel, M.; Matthews, H. K. (2014). "Exploring the Function of Cell Shape and Size during Mitosis". Developmental Cell 29 (2): 159–169. doi:10.1016/j.devcel.2014.04.009. PMID 24780736. 
  40. ^ Lancaster, Oscar; et al. (2013). "Mitotic rounding alters cell geometry to ensure efficient bipolar spindle formation". Developmental Cell 25 (2): 270–283. doi:10.1016/j.devcel.2013.03.014. PMID 23623611. 
  41. ^ a b Lancaster, Oscar; Baum, Buzz (2014). "Shaping up to divide: Coordinating actin and microtubule cytoskeletal remodelling during mitosis". Seminars in Cell & Developmental Biology 34: 109–115. doi:10.1016/j.semcdb.2014.02.015. PMID 24607328. 
  42. ^ a b c Maddox, A. S.; Burridge, K. (2003). "RhoA is required for cortical retraction and rigidity during mitotic cell rounding". Journal of Cell Biology 160 (2): 255–265. doi:10.1083/jcb.200207130. PMID 12538643. 
  43. ^ a b Matthews, H. K.; et al. (2012). "Changes in ect2 localization couple actomyosin-dependent cell shape changes to mitotic progression". Developmental Cell 23 (2): 371–383. doi:10.1016/j.devcel.2012.06.003. 
  44. ^ a b Stewart, M. P.; Helenius, J.; Toyoda, Y.; Ramanathan, S. P.; Muller, D. J.; Hyman, A. A. (2011). "Hydrostatic pressure and the actomyosin cortex drive mitotic cell rounding". Nature 469 (7329): 226–230. doi:10.1038/nature09642. PMID 21196934. 
  45. ^ Fischer-Friedrich, Elizabeth; et al. (2014). "Quantification of surface tension and internal pressure generated by single mitotic cells". Scientific Reports 4 (6213). PMID 25169063. 
  46. ^ a b c d Ramanathan, S. P.; et al. (2015). "Cdk1-dependent mitotic enrichment of cortical myosin II promotes cell rounding against confinement". Nature Cell Biology 17 (2): 148–159. doi:10.1038/ncb3098. PMID 25621953. 
  47. ^ Mantikou, E.; Wong, K.M.; Repping, S.; Mastenbroek, S. (December 2012). "Molecular origin of mitotic aneuploidies in preimplantation embryos". Biochimica et Biophysica Acta - Molecular Basis of Disease 1822 (12): 1921–1930. doi:10.1016/j.bbadis.2012.06.013. PMID 22771499. 
  48. ^ Draviam, V.; Xie, S.; Sorger, P. (2004). "Chromosome segregation and genomic stability". Current Opinion in Genetics & Development 14 (2): 120–5. doi:10.1016/j.gde.2004.02.007. PMID 15196457. 
  50. ^ a b c Iourov, I.Y.; Vorsanova, S.G.; Yurov, Y.B. (2006). "Chromosomal Variations in Mammalian Neuronal Cells: Known Facts and Attractive Hypotheses". In Jeon, Kwang J. International Review Of Cytology: A Survey of Cell Biology 249. Waltham, MA: Academic Press. p. 146. ISBN 9780080463506. 
  51. ^ Shi, Q.; King, R.W. (October 2005). "Chromosome nondisjunction yields tetraploid rather than aneuploid cells in human cell lines". Nature 437 (7061): 1038–1042. doi:10.1038/nature03958. PMID 16222248. 
  52. ^ a b Edgar, B.A.; Orr-Weaver, T.L. (May 2001). "Endoreplication Cell Cycles: More for Less". Cell 105 (3): 297–306. doi:10.1016/S0092-8674(01)00334-8. PMID 11348589. 
  53. ^ a b Lee, H.O.; Davidson, J.M.; Duronio, R.J. (2009). "Endoreplication: polyploidy with purpose". Genes & Development 23 (21): 2461–2477. doi:10.1101/gad.1829209. PMC 2779750. PMID 19884253. 
  54. ^ Italiano, J. E.; Shivdasani, R. A. (2003). "Megakaryocytes and beyond: the birth of platelets". Journal of Thrombosis and Haemostasis 1 (6): 1174–82. doi:10.1046/j.1538-7836.2003.00290.x. PMID 12871316. 
  55. ^ Vitrat, N.; Cohen-Solal, K.; Pique, C.; LeCouedic, J.P.; Norol, F.; Larsen, A.K.; Katz, A.; Vainchenker, W.; Debili, N. (May 1998). "Endomitosis of Human Megakaryocytes Are Due to Abortive Mitosis". Blood 91 (10): 3711–3723. PMID 9573008. 

Cited texts[edit]

Further reading[edit]

  • Alberts, B.; Johnson, A.; Lewis, J.; Raff, M.; Roberts, K.; Walter, P. (2002). "Mitosis". Molecular Biology of the Cell (4th ed.). Garland Science. Retrieved 2006-01-22. 
  • Cooper, G. (2000). "The Events of M Phase". The Cell: A Molecular Approach (2nd ed.). Sinaeur Associates, Inc. Retrieved 2006-01-22. 
  • Lodish, H.; Berk, A.; Zipursky, L.; Matsudaira, P.; Baltimore, D.; Darnell, J. (2000). "Overview of the Cell Cycle and Its Control". Molecular Cell Biology (4th ed.). W. H. Freeman. Retrieved 2006-01-22. 

External links[edit]