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Multinucleate (also multinucleated, polynuclear) cells are eukaryotic cells that have more than one nucleus per cell, i.e., multiple nuclei share one common cytoplasm. Mitosis in multinucleate cells can occur either in a coordinated, synchronous manner where all nuclei divide simultaneously or asynchronously where individual nuclei divide independently in time and space. The multinucleate stage in the life cycle of some organisms is called plasmodium.
Although not normally viewed as a case of multinucleation, plant cells share a common cytoplasm by plasmodesmata, and most cells in animal tissues are in communication with their neighbors via gap junctions.
Mechanisms and types
- Syncytia (formed by cell fusion) and
- Coenocytes (formed by nuclear division not being followed by cytokinesis).
Multinucleate cells can occur naturally under physiological conditions by the fusion of the plasma membranes of cells thus forming syncytia. Examples include the cells of the musculoskeletal systems of mammals, the tapetal cells of plants, and the storage cells of Douglas-fir seeds.
The Chlorarachniophyta form multinucleate cells by fusion, being syncytia and not coenocytes. This syncytia is called plasmodium, in the sense of a multinucleate protoplast without a cell wall which exhibits amoeboid movement.
Furthermore, multinucleate cells are produced from specialized cell cycles in which nuclear division occurs without cytokinesis, thus leading to large coenocytes or plasmodia. In filamentous fungi, multinucleate cells may extend over hundreds of meters so that different regions of a single cell experience dramatically different microenvironments. Other examples include, the plasmodia of slime molds and the schizont of the Plasmodium parasite which causes malaria.
- Boyd, J. D.; Hamilton, W. J. (1966). "Electron microscopic observations on the cytotrophoblast contribution to the syncytium in the human placenta". Journal of anatomy 100 (Pt 3): 535–548. PMC 1270795. PMID 5965440.
- Read, Nick D.; Roca, Gabriela M. (2006). "Chapter 5: Vegetative Hyphal Fusion in Filamentous Fungi". In Baluška, František; Volkmann, Dieter; Barlow, Peter W. Cell-Cell Channels. Landes Bioscience and Springer Science+Business Media. pp. 87–98. ISBN 978-0-387-36058-4.
- Von Aderkas, P.; Rouault, G.; Wagner, R.; Chiwocha, S.; Roques, A. (2005). "Multinucleate storage cells in Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco) and the effect of seed parasitism by the chalcid Megastigmus spermotrophus Wachtl". Heredity 94 (6): 616–622. doi:10.1038/sj.hdy.6800670. PMID 15829985.
- Hoek, C. van den, Mann, D.G. and Jahns, H.M. (1995). Algae An Introduction to Phycology. Cambridge University Press, Cambridge
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