Plasma membrane Nuclear membranes Hormone receptor Adenyla te cyclase ATP Active Protein Kinase A PO 4 G cAMP Inctive Protein Kinase A PO 4 Active pKA enters the nucleus and phosphorylates CREB on Serine 133 Hormone G-protein Core promoter sphorylation of CREB: stimulates interactions with several core promoter proteins induces binding of HAT and acetylation of histones ling mediated by cAMP and protein kina
38
Embed
Plasma membrane Nuclear membranes Hormone receptor Adenylate cyclase ATP Active Protein Kinase A PO 4 G cAMP Inctive Protein Kinase A PO 4 Active pKA enters.
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Plasma membrane
Nuclear membranes
Hormone receptor
Adenylate cyclase
ATP
Active Protein Kinase A
PO4
G
cAMP Inctive Protein Kinase A
PO4
Active pKA enters the nucleus and phosphorylates CREB on Serine 133
Hormone
G-protein
Core promoter
Phosphorylation of CREB: - stimulates interactions with several core promoter proteins - induces binding of HAT and acetylation of histones
Signaling mediated by cAMP and protein kinase A
ATP cAMP(3’,5’cyclic AMP)
PPi
2Pi
H2Opyrohosphatase
Adenylate cyclase
AMP
phoshodiesterase
H2O
cAMP formation cAMP hydrolysis
NO
O
OHO
PO
OH
N
NN
NH2
NO
O
OHOH
P
O
OH
P
O
O
OH
OH
OH
O
O
P N
NN
NH2
Substrate-OH
O ║
Substrate─O ─ P ─ O─
│ OH
Kinase
ATP ADP
Protein-OH
O ║
Protein ─ O ─ P ─ O─
│ OH
Protein Kinase
ATP ADP
Serine-OH
O ║
Serine ─ O ─ P ─ O─
│ OH
Protein Kinase A
ATP ADPSeveral specific Proteins
Including CREB
Several specific proteins
including CREB
CREB and Memory
Signaling by calcium ions
Ca++enters cell
Ca++ activates calmodulin
CaM kinases phosphorylate multiple targets including
ser 133 of CREB
Calmodulin activates CaM kinases
CREB and Memory
CREB and
Memory( in Aplysia,
a slug)
Bailey, Kandel & Kausik (2004) Neuron 44:49-57
Stimulates long term memory
Inhibits long term memory
Amplification:C/EBP is another transcription factor.It activates many genes. (CCAAT box enhancer binding protien)
Two forms of CREB:CREB1 stimulates transcriptionCREB2 represses transcription
A.
B.
A model promoter
TGACTCA GACGTC GGGCGG
SP-1
CREBFos Jun CREB
AP-1 (Fos-Jun binding site)Regulation bygrowth factors,stress, and varioustransmembranesignals
CRE (Cyclic AMPResponse Element)Regulation by cAMP,and by Ca+. Interacts withcore promoter (through CREB Binding Protein)and modifies chromatin structure (through HAT).
SP-1 SiteProvides basalunregulatedtranscriptionalactivity. Manygenes have multiple SP-1 sites