Hydrophobic Signals And Control Of Transcription Flashcards
What can hydrophobic signalling molecules diffuse through?
They can fuse directly through the phospholipid bilayers of membrane so can bind to intracellular receptors
What are the receptors for hydrophobic signalling molecules?
Transcription factors
What are transcription factors?
Proteins that when bound to DNA can either stimulate or inhibit initiation of transcription
What are some examples of hydrophobic signalling molecules?
Steroid hormones: oestrogen and testosterone
What is the pathway of steroid hormones?
They bind to specific receptors in the cytosol or the nucleus to form the hormone-receptor complex. The hormones-receptor complex moves to the nucleus where it binds to specific sites on DNA and affects gene expression. The hormone-receptor complex then binds to specific DNA sequences called hormone response elements. Binding at these sites influences the rate of transcription with each steroid hormone affecting the gene expression of many different genes.