Interestingly, while the knockdown of hts did not cause any significant heart phenotypes (S4A–S4F Fig), the co-expression of htsRNAi and Gcn5RNAi significantly aggravated the heart period length and the arrhythmia index observed upon single knockdown of Gcn5 (S4A and S4C Fig). Here, KAT2B is linked to Arrhythmia.