receptor families

Question 1

classification is done in

Answer 1

order of potency

Question 2

adrenergic agonists

distict potency what is the order for alpha receptors and the response

Answer 2

constricting response

a>nor>isoprenaline

Question 3

adrenergic agonists

distict potency what is the order for beta receptors and the response

Answer 3

dilating response

iso>adr>nor

Question 4

response curve

the lower the potency of blocking needed the

Answer 4

less antagonist needed

Question 5

different potency of adrenaline in the receptor we can get

Answer 5

sub classes

Question 6

classification through gene cloning
how is it done
4 points

Answer 6

identify and sequence cDNA for the receptor
predict AA sequence for receptor
repeat for all receptor subtypes compare AA to give molecular classification
which identifies distinct subtypes by pharmacological classification

Question 7

molecular method that opens up diversity in receptor families
how do we use cDNA to find family types
4 points

Answer 7

find code for receptor using cDNA
look for sequence via oligonucleotide screening
compare sequence to find similar ones
we can change the similarities so that not so similar ones can be found

Question 8

expressed sequence tags ESTs and data mining

what do they do

Answer 8

cDNA gets a EST attached

this sequence is complementary to identical but also homologous receptor subtypes

Question 9

gene sequencing using a computer

Answer 9

it will artificially splice and build a diversity of receptor families from the sequence

Question 10

building post genomic receptor families

G proteins predicted by cDNA what do they contain

Answer 10

7 membrane domains
coupled to g protein
5 families from superfamily of g protein
which are organised with structural similarities

Question 11

receptor types

Answer 11

g protein
tyrosine kinase
ion channel
steroid

Question 12

G coupled receptors
primary
secondary
tertiary

Answer 12

1. multifaced family made up of related subfamilies
2. all receptors predicted to be 7 MD
3. rhodopsin supports 7 MD model

Question 13

ligand gated ion channel
subunits facts about them
4 points

Answer 13

number of related genes encoding subunits
for each receptor type which come together in a mix and match
each subunit exhibits a common transmembrane topology
tertiary structure supported by 3D arrangement of AA sequence

Question 14

ligand gated ion channels

subunits what are they

Answer 14

5 subunits
can be homo-oligomer
hetero-oligomer

Question 15

ions with water bound around what can channels do to remove the water

Answer 15

the water ligands are substituted for protein ligands

this also helps to restrict larger ions from entering the cell

Question 16

tyrosine kinase receptor
primary 
secondary 
tertiary 
quaternary

Answer 16

1. a number of different growth factor gene families
2. single membrane spanning
3. isolated ligand binding domains
4. dimerization required (based on dynamic process)

Question 17

transduction mechanism for tyrosine kinase

Answer 17

dimerization activates it
which is driven by conformational change
the activation activates intinsic kinase
creates a site for phosphotyrosine or SH2 binding site