Heart disease is the leading cause of death in the United States. Therefore, studying the molecular biological processes and molecules, such as proteins, that play a role in a healthy versus diseased heart is important for the creation of therapeutic interventions aimed at reducing heart disease. One protein thought to have an important role in the heart is skNAC (skeletal NACA). skNAC is a striated muscle specific protein found exclusively in skeletal and cardiac muscle. Studies have identified functions of skNAC in skeletal muscle such as being a transcription factor and myoblast differentiation regulator. For its role in cardiac muscle, skNAC has only been studied in association with its binding partner SMYD1 (a histone methyltransferase), where the pair regulate transcription and cardiomyogenesis and are essential for normal embryonic heart development. However, no studies have identified any roles of skNAC alone in the heart. To bridge this gap, our lab aims to examine the effects of skNAC in the heart. The first step in this process was to subject H9c2 cells (derived from rat ventricular myoblasts) to siRNA driven knockdown to silence the skNac gene. To find the most effective way of performing skNac knockdown, we tested different knockdown conditions including different incubation times, altering the amount of siRNAs used, and using undifferentiated cells versus differentiated cells. Using qPCR (gene expression experiments) to verify our results, we concluded that differentiated cells had a significantly higher amount of skNac present before knockdown and had a more prominent reduction of skNac after the knockdown compared to the other knockdown conditions. We hypothesize that because the differentiated cells (myotubes) were more "cardiac muscle cell like" and skNAC is present in cardiac muscle cells, using differentiated cells is the optimal way to perform skNAC knockdown. With these results we hope to study the effects of the knockdown on these H9c2 cells to better understand skNAC's functions in the heart.