RNA Polymerase II, DNA Directed Polypeptide K (POLR2K)

The DNA-dependent RNA polymerase II (EC 2.7.7.6) is responsible for the transcription of protein-encoding genes. It is composed of 10 to 14 subunits ranging in mass from approximately 220 kD (POLR2A) to approximately 7 kD (POLR2K).

The deduced 58-amino acid POLR2K protein has a predicted pI of 9.27. In comparison with the yeast homolog, the C-terminal 25 residues are identical or strongly conserved, whereas the N-terminal end is poorly conserved in size and sequence; both proteins contain conserved cysteine residues that are characteristic of an atypical zinc-binding domain. POLR2K was able to complement the yeast homolog.