Research focuses on the single molecule dynamics of eukaryotic RNA polymerase machinery in living cells. Eukaryotic cells contain three main types of RNA polymerases, of which RNA polymerase II transcribes protein-coding genes, snRNAs, and miRNAs. Each RNA polymerase consists of multiple subunits, for example RNA polymerase II of 10 to 12 subunits including Rpb1 and Rpb2. RNA polymerase catalyzes the synthesis of RNA according to the DNA template by forming phosphodiester bonds between the nucleotides ATP, CTP, GTP and UTP. In eukaryotes, it moves at a speed of 20 nucleotides per second and allows the creation of more than 1000 transcripts from a single gene per hour. Initiation of transcription requires transcription factors that bind to the promoter together with RNA polymerase. The process starts at the promoter and ends at the terminator, while RNA polymerase does not need a primer or a self-repair function.