Communication Flashcards
Paracrine signal
Are secreted by one cell and diffuse to adjacent cells
Autocrine signal
Act on the same cell that secretes the signal
How do paracrine signals work?
1.
2.
3.And a eg
- Diffuse across interstitial fluid
- Because diffusion is a limiting factor they only reach adjacent cells
- Histamine
Neurocrine
Any molecule secreted by a nerve cell
Neurotransmitter
A chemical released by a neuron that influences the neurons target cells
Neuromodulator
Chemicals that later the response of a neuron more slowly then neurotransmitters
Neurohormone
A hormone that is produced and secreted by a neuron
Cytokines what do they control
Cell development
Cell differentiation
The immune response
What makes cytokines different from hormones
They are not produced by specialised cells
Made on demand
Signal transduction
The transmission of info from one side of a membrane to the other using membrane proteins
G proteins are receptors for
Hormones
Growth factors
Neurotransmitters
Inactive G proteins are bound to
GDP
To activate G proteins they
Exchange a GDP for a GTP
What are G proteins linked to
Amplifier enzymes
And what are the most common amplifiers
Adenylyl cyclase
Phospholipid c
What is a trimeric G protein
Alpha beta gamma subunits
Alpha had a GDP attached to it as rest
What happens to activated G protein trimeric subunits
Binding of ligand cause GTP to be gained on the alpha subunit
This results in the alpha subunit leaving the beta gamma complex
In beta adrenergic receptors what does the alpha subunit do
Activates adenylate cyclase
Which converts ATP to cAMP
What does cAMP do
It binds to regulatory subunit of protein kinase A releasing that active catalytic subunit
What happens when ach binds to muscarinic ach receptors
It activates phospholipid c hitch converts the membrane phospholipid into 2 lipid derived secondary messengers
Which 2 secondary messengers are produced by phospholipid c
Diacylglycerol
Inositol trisphosphate
What does diacylglycerol do
It is non polar and interacts with protein kinase c …….
What does inositol trisphosphate do
Binds to ca channels on the ER
Opens them allowing ca to diffuse out
What do integrins do
Mediate blood clotting Wound repair Cell adhesion Recognition in the immune response Cell movement in development
