Notes 11-9-09

1) Initiation-start of transcription
promoter sequence of bases on DNA that RNA polymerase attaches to
sigma factor: subunit of RNA polymerase attaches specifically to promoter units of dna;
most responsible for enzyme attachment to DNA promoter sequence
-there are different sigma factors bind to different sequences
different sigma factors produced in response to different environmental conditions
Dna must be unwound and unzipped before it can be transcribed this is because single dna stranded serves as a template for RNA copy