Amoeboid movement

Two common modes of amoeboid motility

Amoeboid movement is the most typical mode of locomotion in adherent eukaryotic cells.[1] It is a crawling-like type of movement accomplished by protrusion of cytoplasm of the cell involving the formation of pseudopodia ("false-feet") and posterior uropods. One or more pseudopodia may be produced at a time depending on the organism, but all amoeboid movement is characterized by the movement of organisms with an amorphous form that possess no set motility structures.[2]

Movement occurs when the cytoplasm slides and forms a pseudopodium in front to pull the cell forward. Some examples of organisms that exhibit this type of locomotion are amoebae (such as Amoeba proteus and Naegleria gruberi,[2]) and slime molds, as well as some cells in humans such as leukocytes. Sarcomas, or cancers arising from connective tissue cells, are particularly adept at amoeboid movement, thus leading to their high rate of metastasis.

This type of movement has been linked to changes in action potential. While several hypotheses have been proposed to explain the mechanism of amoeboid movement, its exact mechanisms are not yet well understood.[3][4] Assembly and disassembly of actin filaments in cells may be important to the biochemical and biophysical mechanisms that contribute to different types of cellular movements in both striated muscle structures and nonmuscle cells.[5][6] Polarity gives cells distinct leading and lagging edges through the shifting of proteins selectively to the poles, and may play an important role in eukaryotic chemotaxis.[7][8]

  1. ^ Nishigami Y, Ichikawa M, Kazama T, Kobayashi R, Shimmen T, Yoshikawa K, Sonobe S (5 August 2013). "Reconstruction of active regular motion in amoeba extract: dynamic cooperation between sol and gel states". PLOS ONE. 8 (8): e70317. Bibcode:2013PLoSO...870317N. doi:10.1371/journal.pone.0070317. PMC 3734023. PMID 23940560.
  2. ^ a b Preston TM, Cooper LG, King CA (Jul–Aug 1990). "Amoeboid locomotion of Naegleria gruberi: the effects of cytochalasin B on cell-substratum interactions and motile behavior". The Journal of Protozoology. 37 (4): 6S–11S. doi:10.1111/j.1550-7408.1990.tb01139.x. PMID 2258833.
  3. ^ Allen RD, Allen NS (1978). "Cytoplasmic streaming in amoeboid movement". Annual Review of Biophysics and Bioengineering. 7: 469–95. doi:10.1146/annurev.bb.07.060178.002345. PMID 352246.
  4. ^ Smirnova T, Segall JE (October 2007). "Amoeboid chemotaxis: future challenges and opportunities". Cell Adhesion & Migration. 1 (4): 165–70. doi:10.4161/cam.1.4.5305. PMC 2634101. PMID 19262145.
  5. ^ Pollard TD (June 2007). "Regulation of actin filament assembly by Arp2/3 complex and formins". Annual Review of Biophysics and Biomolecular Structure. 36 (1): 451–77. doi:10.1146/annurev.biophys.35.040405.101936. PMID 17477841.
  6. ^ Condeelis J (November 1993). "Life at the leading edge: the formation of cell protrusions". Annual Review of Cell Biology. 9 (1): 411–44. doi:10.1146/annurev.cb.09.110193.002211. PMID 8280467.
  7. ^ Swaney KF, Huang CH, Devreotes PN (April 2010). "Eukaryotic chemotaxis: a network of signaling pathways controls motility, directional sensing, and polarity". Annual Review of Biophysics. 39 (1): 265–89. doi:10.1146/annurev.biophys.093008.131228. PMC 4364543. PMID 20192768.
  8. ^ Kaneshiro, Edna S. (1995). "Amoeboid Movement, Cilia, and Flagella". Cell Physiology Source Book. pp. 611–637. doi:10.1016/B978-0-12-656970-4.50051-8. ISBN 978-0-12-656970-4.