Intro to Receptors Flashcards
What are the requirements for a protein to be targeted by drugs
pocket into which a small molecule can bind
What is the druggable genome
set of genes encoding proteins that can be modulated using experimental small molecule compounds
What are the majority of drugs
small molecules that target proteins
What is main protein target for drugs
receptors
How come receptors are good targets for drugs
recognise specific chemical signals
What happens if a drugs concentration is too high
drug binds to other types of proteins
What does malfunction or loss of receptors lead to
disease
What are the two ways agonists affect receptors
directly or indirectly via transduction mechanisms
What is the effect of direct agonist action on a receptor
ion channel opening or closing
What are the effects of agonists that affect receptors transduction mechanisms
Enzyme activation/inhibition, Ion channel modulation, DNA transcription
Where do antagonists bind on receptors
bind in the same place as the agonist
Describe the mechanism of antagonist action on receptors
Stabilise the receptor, prevents activation and signalling
What do antagonists block when binding to receptors
endogenous mediator action
True or False - receptors cant activate themselves
False
How can receptors activate themselves
float around the cell membrane, change into an active shape
Name drug targets
receptors, channels, enzymes, transporters, microtubules
What is the effect of ion channel blockers
prevent the channel from opening or block the pore
What proteins do modulators target
channels
What do modulators affect
the gating mechanism of channels
What is the effect of modulators affecting gating mechanism
increase or decrease opening probability
Where are enzymes normally found
inside cells
What are the two types of drugs that target ion channels
blockers, modulators
What are the types of drugs that target enzymes
inhibitors, false substrate, prodrug
What is the effect of inhibitor drugs on enzymes
inhibit normal reaction and function of enzyme
What is the effect of false substrate drugs on enzymes
enzyme makes an abnormal metabolite
How do pro drugs work
metabolised by the enzyme to create an active drug
What types of drug target transporters
inhibitors, false substrates
What do transporters require to function
concentration gradient or energy
How do inhibitors affect transporters
bind into transporter pocket and prevent function
How do false substrates affect transporters
use transporter to get across the CM, abnormal compounds build up
Name two drugs that target microtubules
colchine, paclitaxel
What does colchine treat
gout
What is gout
inflammatory disease
How does colchine treat gout
interferes with inflammatory response and microtubule stability
What is paclitaxel
chemo therapeutic drug
How does paclitaxel work
stabilises the microtubule, preventing cell division
What are the different types of receptor
ligand gated ion channels, GPCRs, kinase linked receptor, nuclear receptors
What are the two features of ligand gated ion channel structure
built in ligand binding site, sequence of AAs with pore
What are the two structural features of GPCRs
identifiable ligand binding sites, 7 transmembrane spanning domains
What do GPCRs require to signal
GTP binding protein
Describe the structure of kinase linked receptors
single transmembrane domain, ligand binding site sticks out of the cell
What is the signal that binds to kinase linked receptors dependant on
kinase signalling cascade
Describe the structure of nuclear receptors
lack transmembrane domains, not anchored to CM, DNA binding domain
How do nuclear receptors exert their actions
DNA binding domain
What are the four families of ligand gated ion channels
Cys loop, glutamate, P2X, and calcium release
How many transmembrane spanning domains do the Cys loop family have
4
How many transmembrane domains does the glutamate family have
3
What part of the glutamate ion channel is the pore
re-enterant loop
What is the ligand for the P2X receptor
ATP
Where are calcium release type ion channels found
intracellular membranes, endoplasmic reticulum
