Lecture 2 Flashcards
(25 cards)
kinase linked receptors
activation leads to protein phosphorylation, causing gene transcription and protein synthesis
first messengers
one signal molecule (receptor agonist) binds the receptor
second messengers
are released on binding of a first messenger. e.g. cAMP and IP3
adenylyl cyclase
converts ATP into cAMP when stimulated by GPCR
collision coupling theory
unbound receptors stop moving when agonist binds, which allows G protein to bind
shuttle model
the continuous switch between low-affinity and high affinity state in a cycle
Gas
stimulates AC, increased cAMP
Gai
inhibits AC, decreased cAMP
Gao
limited effects of alpha subunit. mostly beta gamma
Gaq
activates PLC, increased IP3 and DAG
PDE
phosphorylates cAMP
PDE5
inhibiting increases vasodilation (viagra), by decreasing the conversion of cGMP to 5’GMP
PI turnover
IP3 cycle of formation and degradation
homologous desensitization
activated receptor causes desensitization of itself
heterologous desensitization
activated receptor causes desensitization of a receptor in another signalling pathway
cytokine
protein that helps control inflammation
SH2
src homology 2 domain
Jak
janus kinase
stat
signal transducers and activator of transcription
nuclear receptors
receptors for hormones
binding of complex to GRE causes…
increased transcription
binding of complex to nGRE causes…
prevention of gene expression
nicotinic acethylcholine receptor
only activated when two ACh are bound.
temporal summation
two impulses generated by the same axon closely to each other can pass the threshold
