Cell Signalling – Non-Steroid Cell Signalling – Non-Steroid
Hormones Hormones
The hormone itself is known as the
first messenger, and it binds to a
receptor on the cell surface
membrane.
This causes the release of a G protein
in the membrane which activates the
enzyme adenyl cyclase.
Adenyl cyclase is an enzyme that
converts ATP into cyclic AMP.
Cyclic AMP is the secondary
messenger molecule, it activates a
cascade of enzyme-controlled
reactions that alter the activity of the
cell.
Cell Signalling – Steroid Hormones Cell Signalling – Steroid Hormones.
The steroid hormone passes directly
through the phospholipid bilayer
(since it is lipid soluble).
The hormone binds to a receptor in
the cytoplasm.
The receptor-hormone complex
enters the nucleus of the cell and acts
as a transcription factor on DNA.
It will either promote or inhibit the
transcription of a gene.
Hormones Hormones
The hormone itself is known as the
first messenger, and it binds to a
receptor on the cell surface
membrane.
This causes the release of a G protein
in the membrane which activates the
enzyme adenyl cyclase.
Adenyl cyclase is an enzyme that
converts ATP into cyclic AMP.
Cyclic AMP is the secondary
messenger molecule, it activates a
cascade of enzyme-controlled
reactions that alter the activity of the
cell.
Cell Signalling – Steroid Hormones Cell Signalling – Steroid Hormones.
The steroid hormone passes directly
through the phospholipid bilayer
(since it is lipid soluble).
The hormone binds to a receptor in
the cytoplasm.
The receptor-hormone complex
enters the nucleus of the cell and acts
as a transcription factor on DNA.
It will either promote or inhibit the
transcription of a gene.
