Cell culture

Human carcinoma cells (HeLa, The Russian collection of human, animals and plants cell cultures, Institute of Cytology, St. Petersburg, Russia) were grown in Dulbecco’s modified Eagle’s medium (Paneco, Moscow, Russia) supplemented with 10% heat-inactivated fetal bovine serum (HyClone, Logan, UT, USA), 2 mM L-glutamine (Paneco, Moscow, Russia) and antibiotic-antimycotic solution (Gibco, Waltham, MA, USA). To inhibit RNA transcription, the cells were grown in medium with 0.1 μg/ml actinomycin D (ActD). Cellular transfection was performed using the Lipofectamine 2000 reagent (Invitrogen, Waltham, MA, USA) according to the manufacturer’s instructions.