Fig. 7
Model of Cardiomyocyte Polyploidization as a Barrier to Heart Regeneration
(A) Hearts composed almost exclusively of diploid cardiomyocytes (1×2c), such as those in the adult zebrafish and mouse neonate, regenerate efficiently after amputation through myocardial proliferation.
(B) In mosaic hearts composed of diploid (GFP−) and polyploid-enriched (GFP+) cardiomyocyte populations, diploid cardiomyocytes proliferate actively to replace injured muscle, with minor contributions from the polyploid-enriched population.
(C) Minimizing the proportion of diploid cardiomyocytes in the zebrafish heart, a situation similar to that in adult mammals, including humans, results in reduced cardiomyocyte proliferation and persistent scarring.
Dashed line, plane of amputation; dark area, amputated tissue; blue boxes, regenerated myocardium; red and green cells, diploid and polyploid-enriched cardiomyocyte populations.
Reprinted from Developmental Cell, 44, González-Rosa, J.M., Sharpe, M., Field, D., Soonpaa, M.H., Field, L.J., Burns, C.E., Burns, C.G., Myocardial Polyploidization Creates a Barrier to Heart Regeneration in Zebrafish, 433-446.e7, Copyright (2018) with permission from Elsevier. Full text @ Dev. Cell