Cell - Cell signalling Flashcards
Agonist?
activate receptors, changes cell behaviour
Antagonist?
blocks and prevents activation of cell receptors
Why may you need to activate a receptor?
- regulate cellular processes
- cell communication
- coordination response
Magic bullet?
drug with no side effects
Types of Signalling molecules?
- gases e.g. NO,CO
- amino acids e.g. glycine
- Small peptides e.g. growth factors
- Proteins e.g. insulin, cytokines
- steroids e.g. cortisol
Gap junction transport :
no chemicals , in heart muscle it synchronises contraction
Receptor mediated transport;
synthesised, packaged in vesicles, exocytosis and transport detected by receptors on target cell
Types of receptor
ionic
Contact Dependent - membrane proteins communicate with neighbour or the ECM
G protein coupled
Enzyme linked
Autocrine signalling?
short distance cell signals to itself, binds to own receptors, used in development to reinforce change e.g. cancer cells can send growth factors to itself to cause proliferation
Paracrine signalling
short distance to neighbour e.g. aspirin is analgesic drug that interferes with paracrine signalling from injured tissue that tells surrounding tissue to swell or fever or pain
Endocrine signalling
long distance, distributed widely secreted int o bloodstream e.g. hormone
Synaptic signallling
neurones, ligand is a neurotransmitter long or short distance
Intracellular signalling cascade steps :
- relay proteins - pass the message
- Adaptor protiens - link signalling proteins don’t participate
- Bifurcation proteins - take message to another signalling pathway
- Transducer proteisn - convert signal to another form
- Integrator protien - integrates signal from different pathways then relays signal forward
- Latent gene regualtory proteins - migrate to nucleus when activated
RAB TIL
+ve and -ve signalling ?
\+ve = amplify signal -ve = to terminate signal
