<prompt> Sigma s subunit is present in:80 S subunitRNA polymeraseRequired for initiation of replicationDNA polymerase  <response>: RNA POLYMERASE DNA dependent RNA polymerase Complex holoenzyme with five polypeptides units Five polypeptides - 2 alpha , 1b , 1b , one sigma Sigma subunit enables the core enzyme to recognize and bind the promoter region to form the preinitiation complex PIC. b-Main catalytic activity b binds to DNA template 