Spore-specific modification of DNA-dependent RNA polymerase α subunit in streptomycetes — a new model of transcription regulation

摘要

At the very beginning of spore germination in streptomycetes the full-length α subunit of DNA-dependent RNA polymerase is shortened from its C-terminus. The C-terminal domain of the protein is required for binding of DNA and transcription regulators but its regulatory role in streptomycetes was not extensively studied. Comparison of the sequences ofE. coli andS. coelicolor RNA polymerase α subunit (RNAPα) C-terminal domains reveals that the majority of amino acid residues responsible for the interaction with transcription regulators is conserved in both microorganisms. The spore specific modification of streptomycete RNAPα could thus have its regulatory role. The nature of the proteolytic enzyme, responsible for the RNAPα cleavage is discussed.