• Question: Could you go into more detail about transcriptional regulation - does it occur in all types of organisms, or just humans? Do they do anything except what you descibed and controlling how much RNA is created?

    Asked by maddybishop to Seyyed on 14 Jun 2012.
    • Photo: Seyyed Shah

      Seyyed Shah answered on 14 Jun 2012:

      I liked reading your question. I also think you have thought hard about the topic and raised some very good points.

      Because all living things have genes, transcription regulation happens in all organisms. Even in viruses, which are the smallest living things.

      Regulating genes means, as you have stated, controlling how much RNA is made. But, transcription regulation can also have an effect on the next step, which is translation. All the information stored in the DNA of a gene is copied exactly into RNA. The information in RNA is used to make proteins.

      Translation (making protein from RNA) can be affected by transcription. For example, transcription regulation can indirectly slow down or speed up translation.

      Also, during transcription some RNA is edited (bits are cut out) so different versions of the same protein (with bits missing) can be made. This is called splicing. So, the same DNA can code for proteins with small differences, which can have slightly different functions.

Comments

  • Photo: Judith

    Judith commented on :

    Excellent question, Maddy, and an excellent summary from Seyyed as well. Genes are regulated at lots of different stages. All cells with a nucleus use RNA splicing to get a wider variety of proteins from their genes and splicing can also affect how much protein is made by affecting how long each RNA molecule hangs around in the cell: you can make lots of copies of a protein from a single RNA. We’re still just scratching at the surface of all the complex ways cells can regulate their genes. That’s why it’s such an exciting area to work in.