RATIONALE Polyploidy and multinucleation are characteristic features of mammalian cardiomyocytes, which develop shortly after birth when most differentiated cardiomyocytes become acytokinetic. Cardiac overload and hypertrophy further increase the degree of polyploidy of cardiomyocytes, suggesting a role in cell type-specific responses to physiological and pathological stimuli. OBJECTIVE We so...

Liu et al have discovered a potent promoter of polyploidy in rat hearts. Polyploidy—multiple copies of the genome in one cell—is normal in cardiomyocytes but can also be ramped up in pathological situations, such as cardiac hypertrophy or in regenerative situations, such as after heart injury. The ability to boost or suppress polyploidy might thus have a number of heart health implications. Car...

Although polyploidy has been involved in speciation in both animals and plants, the general perception is often that it is too rare to have been a significant factor in animal evolution and its role in plant diversification has been questioned. These views have resulted in a bias towards explanations for what deters polyploidy, rather than the somewhat more interesting question of the mechanism...

The molecular mechanism responsible for cell fate after mitotic slippage remains unclear. We investigated the different postmitotic effects of aneuploidy versus polyploidy using chemical inhibitors of centromere-associated protein-E (CENP-E) and kinesin family member 11 (KIF11, also known as Eg5). Aneuploidy caused substantial proteotoxic stress and DNA damage accompanied by p53-mediated postmi...

Chromosome evolution in flowering plants is often punctuated by polyploidy, genome duplication events that fundamentally alter DNA content, chromosome number, and gene dosage. Polyploidy confers postzygotic reproductive isolation and is thought to drive ecological divergence and range expansion. The adaptive value of polyploidy, however, remains uncertain; ecologists have traditionally relied o...

Whole-genome duplication (WGD), or polyploidy, is a major force in plant genome evolution. A duplicate of all genes is present in the genome immediately following a WGD event. However, the evolutionary mechanisms responsible for the loss of, or retention and subsequent functional divergence of polyploidy-derived duplicates remain largely unknown. In this study we reconstructed the evolutionary ...