EL1 Flashcards
What is gating?
the process by which ion channel opening and closing is controlled.
ie voltage gated ion channel.
What is the G protein Gs coupled to?
Adenylate cyclase (positively)
What is IP3?
Inositol tris-phosphate.
a second messenger produced in the phospholipase C pathway.
coupled to Gq.
what is transrepression?
the process by which nuclear hormone receptors decrease expression of a protein.
What is the structure of a ligand gated ion channel?
4 transmembrane domains.
N terminus extracellular.
large loop between TM3 and TM4. TM2 forms lining of channel
what receptor class is most frequently targetted by drugs?
G protein coupled receptors.
what is an orphan receptor?
a receptor for which the endogenous ligand is not known.
what is phosphlipase C linked to?
Gq
What is transactivation?
process by which NHR increase expression of a protein.
What is the structure of a voltage gated sodium/calcium channel?
24 TM domains, 4 psuedo subunits.
TM4 is the voltage sensor.
membrane dipping loop between TM5 and TM6.
N terminus intracellular.
What is a G protein coupled receptor?
receptor for a neurotransmitter, hormone or other signalling molecule that is coupled to intracellular signalling pathways via G proteins.
What is a G protein?
name
guanine nucleotide binding protein.
links GPCR to intracellular signalling pathways.
Trimeric - alpha, beta, gamma.
Gs, Gi, Gq main types.
built in GTPase enzyme activity.
what is the most diverse receptor class?
GPCR.
what is Gi coupled to?
adenylate cyclase (negatively)
where are NHR usually present?
cytoplasm
what is the structure of a GPCR subunit?
7 TMD
N terminus extracellular
large loop between TM5 and TM6.
what is a ligand gated ion channel.
ion channel with a binding site for a neurotransmitter, built into it.
channel opened by actions of neurotransmitter.
what is Gq coupled to?
phospholipase C
in transactivation what must NHR do before entering the nucleus.
bind to the ligand, dissociate from heat shock proteins and dimerize.
what is adenylate cylase bound to?
Gs and Gi
