Diverse system stresses: common mechanisms of chromosome fragmentation. Cell Death Dis 2:e178-e186

The Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI 48201, USA.
Cell Death & Disease (Impact Factor: 5.01). 06/2011; 2(6):e178. DOI: 10.1038/cddis.2011.60
Source: PubMed


Chromosome fragmentation (C-Frag) is a newly identified MCD (mitotic cell death), distinct from apoptosis and MC (mitotic catastrophe). As different molecular mechanisms can induce C-Frag, we hypothesize that the general mechanism of its induction is a system response to cellular stress. A clear link between C-Frag and diverse system stresses generated from an array of molecular mechanisms is shown. Centrosome amplification, which is also linked to diverse mechanisms of stress, is shown to occur in association with C-Frag. This led to a new model showing that diverse stresses induce common, MCD. Specifically, different cellular stresses target the integral chromosomal machinery, leading to system instability and triggering of MCD by C-Frag. This model of stress-induced cell death is also applicable to other types of cell death. The current study solves the previously confusing relationship between the diverse molecular mechanisms of chromosome pulverization, suggesting that incomplete C-Frag could serve as the initial event responsible for forms of genome chaos including chromothripsis. In addition, multiple cell death types are shown to coexist with C-Frag and it is more dominant than apoptosis at lower drug concentrations. Together, this study suggests that cell death is a diverse group of highly heterogeneous events that are linked to stress-induced system instability and evolutionary potential.

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    • "As MN may merge back with the main nucleus, this will result in the rearranged chromosomes becoming a part of the genome as described by Janssen et al. [2011]. cell death called chromosome fragmentation [Stevens et al. 2011; Stevens et al. 2007]. Notably, unbalanced partial chromosomal losses and gains have also been observed in fragmented aneuploid embryos and not euploid embryos, to suggest a relationship between sub-chromosomal instability and aneuploidy in the human embryo [Chavez et al. 2012; Vanneste et al. 2009]. "
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