cGMP

1
Return to the dark state
disk membrane
plasma membrane
dark
T
PDE
NCKX (light-insensitive)
R
b
K,Ca
a
g
Na
g
a
Ca2 0.5-1 mM
cations
b
CNG channel open
b
a
g
Ta
g
CNG channel closed
PDE
cGMP
Gb5
GTP
R9AP
Ca2
G
-Ca2
Ca2 100 nM
Ca2
Ca2
GC/ GCAP
light
Ca2
Ca2
Ca2
GCAP2
IPM
disk surface
cytoplasm