Figure 1.

(a) Example of experimental traces of the membrane potential from the experiment by Nadadur et al. [27]. Delayed afterdepolarizations (DADs) and spontaneous depolarizations (SDs) occur for a majority of (homogeneous TBX5 knockout) mice atrial myocytes, but none for control mice atrial myocytes. (b) Simplified schematic highlighting that reduced expression of TBX5 reduces sarcoplasmic reticulum Ca²⁺ ATPase 2a (SERCA) and increases I_NaCa and I_CaL, respectively. (Online version in colour.)