Transcription factor codes
Genes translated into proteins which bind to regions of DNA within the nucleus, controlling
transcription of other genes.
In this example of a transcription factor code: the absence of transcription factor expression causes a
cell to form into cell type 1; the presence of transcription factor 1 causes a cell to become cell type 2;
the presence of both transcription factor 1 and 2 causes the cell to become cell type 3.
Transcription factor mutants: homeotic mutant = one cell type/tissue/structure becomes another
type
Signal transduction carries the signal from the cell membrane to the nucleus:
Inductive signals induce different fates:
e.g. at a low dose no transcription factors are switched on, TF1 needs a medium dose and TF2 needs
a high dose to be switched on.
Experiments to understand inductive signals: experimental embryology is a
way of finding inductive signals. 3 steps:
Genes translated into proteins which bind to regions of DNA within the nucleus, controlling
transcription of other genes.
In this example of a transcription factor code: the absence of transcription factor expression causes a
cell to form into cell type 1; the presence of transcription factor 1 causes a cell to become cell type 2;
the presence of both transcription factor 1 and 2 causes the cell to become cell type 3.
Transcription factor mutants: homeotic mutant = one cell type/tissue/structure becomes another
type
Signal transduction carries the signal from the cell membrane to the nucleus:
Inductive signals induce different fates:
e.g. at a low dose no transcription factors are switched on, TF1 needs a medium dose and TF2 needs
a high dose to be switched on.
Experiments to understand inductive signals: experimental embryology is a
way of finding inductive signals. 3 steps:
