Definitions

  • Central dogma: DNA – RNA – PROTEIN
  • Transcription: copying the information from DNA into mRNA (messenger RNA)
  • Involving 3 major phases: Initiation, elongation and termination
Required steps
  1. chromatin change into the active form (Eukaryotic genome organisation in general (definitions))
  2. basic transcription factor binds to the opened sequence’s promoter region
  3. control elements bind to the sequence of the current gene (enhancers, silencers, special transcriptional factors)
  4. activation of RNA polymerase II
  5. transcription – production of mRNA (pre-mRNA)

Processes

  1. Initiation: The transcription start site of eukaryotic genes is usually embedded in the so-called minimal or core promoter: an 80 bp region containing several short conserved DNA elements, and the transcription start site.
  2. Elongation: it occurs in a bubble of the unwound DNA, where the RNA Polymerase II uses ssDNA as a template to perform the synthesis of a new mRNA strand in the 5′ to 3′ direction.
  3. Termination: RNA Polymerase II terminates the process at random locations past the end of the gene. The newly-synthesized pre-mRNA is cleaved at a sequence-specified location and released before transcription is terminated.

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