Endomitosis


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Related to Endomitosis: endometritis, adenomyosis, endoreduplication

endomitosis

[¦en·dō‚mī′tō·səs]
(cell and molecular biology)
Division of the chromosomes without dissolution of the nuclear membrane; results in polyploidy or polyteny.

Endomitosis

 

in many plants and some animals, doubling of the number of chromosomes in the nuclei of cells.

In contrast to mitosis, the nuclear membrane and the nucleolus are not destroyed, the cleavage spindle does not form, and reorganization of the cytoplasm does not occur. However, the chromosomes do go through the cycle of spiralization and despiralization. Repeated endomitoses lead to the development of giant polyploid nuclei, resulting in an increase of deoxyribonucleic acid (DNA) in the cell. The term “endomitosis” also denotes the process of repeated doubling of the nucleoprotein threads (chromonemata), which constitute the core of the chromosomes, without an increase in the number of the chromosomes. As a result of the substantial increase in the amount of DNA in the nuclei, giant (polytenic) chromosomes form.

References in periodicals archive ?
Accordingly, we narrowed our analysis of potential RRI and SI targets in endomitosis to cell cycle regulators, especially to p53, p21, cyclinB1, and [beta]-actin.
These results are significantly far away from the normal process of endomitosis and apoptosis that happens constantly in the liver.
Some studies performed with antimitotic substances showed us that increase in chromosome number and endomitosis of the cell causes the formation of MN.
In this case the somatic chromosome number may be restored to the eggs by premeiotic endomitosis or abortive meiosis (Cuellar, 1987).