Lastly, MC3 was enriched for genes associated with the cell cycle, such as pcna and mki67, indicating that macrophage proliferation also occurs during cardiac regeneration in zebrafish, similar to the proliferation observed in mouse hearts following myocardial infarction (Sager et al., 2016; Supplementary Figure S7A, B and Table S1). This evidence concerns the gene PCNA and myocardial infarction.