Modulating Retrotransposon Activity in BmN Cells

Azidothymidine (AZT) is a widely used RT inhibitor that can inhibit endogenous RT activity (9 (link)). GSK-LSD1, an inhibitor of histone H3 lysine 9 (or histone H3 lysine 4) demethylases, has been reported to increase the methylation level of histone H3 lysine 9, thus increasing RT activity in mammalian cells. In this study, AZT (China, Absin, Cat: abs810874) and GSK-LSD1 (USA, Selleck, Cat: S7574) were used to modulate the retrotransposon activity of RT in BmN cells. MTT assays were carried out to determine the proper drug concentration for subsequent experiments. Briefly, 10³ BmN cells were seeded in 96-well plates and treated with different concentrations of AZT (0, 1, 5, 10, 25, 50, 100 mM) or GSK-LSD1 (0, 1, 5, 10, 25, 50, 100 nm) for 24 h. Cells viability was evaluated by MTT. According to MTT assay, BmN cells were treated with 5 mM AZT and/or 50 nM GSK-LSD1 in the subsequent experiments. Before further treatments, BmN cells were seeded in 6-well plates at the density of 1× 10⁶ cells/well and cultured for one day. Thereafter, cells were pretreated with 5 mM AZT for 4–6 h or 50 nM GSK-LSD1 for 24 h, followed by BmCPV infection and other downstream assays.