Transcriptional factors

• What are transcriptional factors?

  Proteins that regulate gene expression
• How do transcription factors work?

  Bind to a base sequence of DNA causing it to start transcription, which produced mRNA which produces a polypeptide

  When a gene is switched off, the site on the transcription factor is inactive
• What is the role of oestrogen?

  Diffuses through the phospholipid bilayer and binds to the transcription factor

  This changes the shape of the binding sit on the transcription factor, so it can bind to DNA