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What is Sigma (s) subunit is present in: and explain in detail?
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