A protein component usually associated with RNA polymerase can be separated from the enzyme by chromatography on phosphocellulose. The polymerase is unable to transcribe T4 DNA unless this factor is added back.

Factor stimulating transcription by RNA polymerase.

Three distinct RNA polymerase activities have been isolated from developing sea urchin embryos. In rat liver nuclei there are two RNA polymerase activities. One polymerase (I) is probably localized in the nucleolus and one (II) in the nucleoplasm.

Multiple Forms of DNA-dependent RNA Polymerase in Eukaryotic Organisms

A new T7-specific RNA polymerase is found in T7 phage-infected cells It is the product of T7 gene I and is physically and biochemically distinct from the host cell RNA polymerase The synthesis of T7 RNA polymerase provides a direct explanation for the pleiotropic control of late T7 functions exerted by gene I

New RNA polymerase from Escherichia coli infected with bacteriophage T7.

Separation and characterization of the subunits of ribonucleic acid polymerase.

The RNA polymerase σ factor is required for the initiation of RNA synthesis. After initiation σ is released from the polymerase-factor complex and from the DNA template, and may then be re-used by another polymerase molecule to initiate a new RNA chain.

Cyclic re-use of the RNA polymerase sigma factor.

IT is generally believed that genetic transcription is carried out by an enzyme, DNA-dependent RNA polymerase1, which is capable of copying DNA sequences into RNA sequences. The enzyme requires DNA and the four naturally occurring ribonucleotide triphosphates to produce RNA which is a faithful copy of the DNA template2 in terms of base composition, nearest neighbour analysis and DNA–RNA hybridization3.

G P Tocchini-Valentini

Papers

Mutant of E. coli containing an altered DNA-dependent RNA polymerase.