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Chem 509 Signal Transduction Winter 2012 Lecture 2
Chem 509Signal Transduction
Winter 2012
Lecture 2
What difference between Gs, Gq and Gi?:
1. Gs, G protein that is stimulatory and binds AC2. Gq, G protein that is stimulatory and binds PLC3. Gi, G protein that is inhibitory and binds AC.
O
H
H
O
OH
HH
OH
OH
OH HP
O
O
O-
H2C
CHOC
O
R2
H2C O C
O
R1 P-O
O-
O
P
O
O-
O-
Phosphatidylinositol
O
H
H
OH
OH
HH
OH
OHH
OH HP
O
O
O-
H2C
CHOC
O
R2
H2C O C
O
R1
Phosphatidylinositol-diphosphate
Phospholipases
Phospholipase A1-can hydrolyze the sn-1 acyl bond but can alsohydrolyse the sn-2 acyl bond. In the former case, this liberates a fatty acid and 2-acyl-glycerophospholipid.
O
H
H
O
OH
HH
OH
OH
OH HP
O
O
O-
H2C
CHOC
O
R2
H2C O C
O
R1 P-O
O-
O
P
O
O-
O-
O
H
H
O
OH
HH
OH
OH
OH HP
O
O
O-
H2C
CHOC
O
R2
H2C O C
O
R1 P-O
O-
O
P
O
O-
O-
Phospholipases
Phospholipase A 2-hydrolyzes the sn-2 acyl bond. This liberates a fatty acid and a lysophospholipid (1-acyl-glycerophospholipid)
O
H
H
O
OH
HH
OH
OH
OH HP
O
O
O-
H2C
CHOC
O
R2
H2C O C
O
R1 P-O
O-
O
P
O
O-
O-
Phospholipases
Phospholipase C-hydrolyzes one phosphoester bond to generate diacyglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3).
O
H
H
O
OH
HH
OH
OH
OH HP
O
O
O-
H2C
CHOC
O
R2
H2C O C
O
R1 P-O
O-
O
P
O
O-
O-
Phospholipases
Phospholipase D-will hydrolyse the other phosphoester bond to generate phosphatidic acid (amphiphilic product) and inositol 4,5 diphosphate (IP2).
PI=Phosphatidylinositol, Phosphorylated derivatives of PI are denoted as PIPx.PC=Phosphatidylcholine
PA=Phosphatidic acidLyso PC= deacylated phosphatidylcholine
Calmodulin
End of GPCR lecture story
Begin insulin signaling story
Insulin signaling
Insulin signaling
Other Receptor Tyrosine Kinase Receptors
Adaptation of insulin-mediated growth signal
Brief overview of cancer signaling pathways
Cell cycle
