To mention a few specific examples we observed that many myosin proteins were nitrosylated, e.g. the proteins encoded by Myl4, Myh4, Myh6, Myl3, Myh3, Mybpc3 and Tpm1. Many of these proteins were also methylated, such as proteins encoded by Myl9, Myh11, Myh7, Myl3, Myh6, Myh8, Tba3c, Tpm1, Tpm2, Tpm3, Ctna2 and Desm. To illustrate that the PTMs we report herein are also localized to cardiac specific proteins we here discuss modifications for a few proteins, where their dysfunction are linked to cardiac disease states. Here, MYL4 is linked to heart disorder.