5.3 Transcription factors
At various places in this course, reference is made to new proteins being made, or to genes being switched on. The control of gene transcription is a hugely complex area and well beyond the scope of this course. However, it is helpful to know that for any gene to be switched on, for any new protein to be made (or an old protein replaced), an appropriate transcription factor must be present, and it must couple with an appropriate part of the DNA. In biological terms a transcription factor is a molecule which attaches to a specific part of the genome and allows a gene to be transcribed. In other words the transcription factor is the signal for the transcription of a particular gene, and the production of a specific protein.
A transcription factor was described, but not named, in Section 5.2. Of what was it composed?
The transcription factor was composed of the hormone oestradiol and its receptor.
Very often there are several components to a transcription factor, and they must all be present for it to work, for transcription to take place.