regulation of vertebrate neuron death in …
TRANSCRIPT
REGULATION OF VERTEBRATE NEURON DEATH IN DEVELOPMENT AND NEURODEGENERATION:
ROLE OF TRANSCRIPTION
LLOYD A. GREENECOLUMBIA UNIVERSITY
NEW YORK, NY
• BEARD (1889) - LOSS OF NEURONAL POPULATIONS IN FISH (ROHON-BEARD NEURONS)
• COLLIN (1906) - DEATH OF MANY SENSORY AND MOTOR NEURONS IN THE CHICK EMBRYO
MASSIVE LOSS OF NEURONS DURING VERTEBRATE DEVELOPMENT HAS BEEN
LONG KNOWN
0
5,000
10,000
15,000
20,000
25,000
36 38 40 42 44 46 P2 P4
NORMAL
DEVELOPMENTAL STAGE
NEU
RO
N N
UM
BER
IN C
HIC
K IO
N
APPROXIMATELY 50% OF POST-MITOTIC NEURONS DIEDURING NORMAL DEVELOPMENT
Clarke, Rogers & Cowan J. Comp. Neurol. 167: 125 (1976)
DEATH OF PROLIFERATING VZ CELLS IN E14 MOUSE CEREBRUM
Blaschke et al J Comp Neurol 1998
Tan = BrDU; Purple = ISEL/dying
FROM Barres and Raff, Journal of Cell Biology, Volume 147, Number 6, December 13, 1999 1123-1128
REGULATED DEVELOPMENTAL DEATH OF OLIGODENDROCYTES
0102030405060708090
100
GENERATED 3 DAYS
SURVIVIOLIGOSOLIGO
SURVIVAL
VIKTOR HAMBURGER AND RITA LEVI-MONTALCINI AND THEBEGINNING OF THE NEUROTROPHIC THEORY OF
DEVELOPMENTAL NEURON DEATH IN VERTEBRATES
SARCOMA EXTRACT
LEVI-MONTALCINI AND HAMBURGER DISCOVER A SOLUBLE NERVE-GROWTH PROMOTING ACTIVITY (NGF)
IN EXTRACTS OF SARCOMA 180
EVIDENCE FOR THE ROLE OF GROWTH FACTORS IN REGULATING DEVELOPMENTAL NEURONAL DEATH IN VIVO
1. INJECTION OF NEW BORN MICE WITH NGF ANTIBODIES YIELDS “IMMUNOSYMPATHECTOMY”
MOTHERS AUTOIMMUNIZED AGAINST NGF PRODUCE OFFSPRING WITH MANY FEWER DORSAL ROOT GANGLIONIC NEURONS
2. SUPPLY OF EXOGENOUS NGF BLOCKS DEVELOPMENTAL CELL DEATH
OF SYMPATHETIC NEURONS
EVIDENCE FOR THE ROLE OF GROWTH FACTORS IN REGULATING DEVELOPMENTAL NEURONAL DEATH IN VIVO
MICE NULL FOR NGF OR ITS RECEPTORS SHOW EXCESS NEURONAL DEATH.
Fagin et al. J Neurosci (1996)
0
5,000
10,000
15,000
20,000
25,000
36 38 40 42 44 46 P2 P4
NORMAL
DEVELOPMENTAL STAGE
NEU
RO
N N
UM
BER
IN C
HIC
K IO
N
NORMAL DEVELOPMENTAL NEURONAL DEATH OCCURS ANDIS REGULATED BY TARGET DERIVED TROPHIC FACTORS
Clarke, Rogers & Cowan J. Comp. Neurol. 167: 125 (1976)
ENUCLEATED
125I-NGF
SCG
050
100150200250300350400450
0 8 16 24 32 40 48
CONTRATERALIPSILATERAL
HOURS
CPMIn SCG
RETROGRADE TRANSPORT OF NEUROTROPHINS FROM TARGETS
Ian Hendry & Hans Thoenen
ALL TROPHIC SUPPORT DURING DEVELOPMENT IS NOT NECESSARILY TARGET DERIVED - WHAT KEEPS
NEURONS ALIVE BEFORE THEY INTERACT WITH THEIR TARGETS?
AUTOCRINE LOOPS -NEURONS CAN MAKE THEIR OWN NEUROTROPHIC FACTORS (CORTICAL NEURONS; BDNF)
TISSUE EN ROUTE TO TARGET MAY PROVIDE TROPHIC FACTORS (SUCH AS NT3 AND BDNF)
NEUROTROPHINSNGFBDNFNT3NT4/5
EGF FAMILYEGFTGFαNEUREGULINS
FGF FAMILY
INSULIN & IGFs
TGFβ SUPERFAMILYTGFβBMPsGDNFARTEMINNURTURINPERSEPHIN
CYTOKINESCNTFLIFINTERLEUKINS
PDGF
HGF FAMILYHGFMSP
NEUROPEPTIDESPACAPVIP
GROWTH FACTORS THAT CAN MAINTAIN SURVIVAL OF SELECT NEURONAL POPULATIONS
0102030405060708090
100
GENERATED 3 DAYS
SURVIVIOLIGOS
NEUREGULIN, PDGF
FROM Barres and Raff, Journal of Cell Biology, Volume 147, Number 6, December 13, 1999 1123-1128
REGULATED DEVELOPMENTAL DEATH OF OLIGODENDROCYTES
REMOVAL OF NEURONS WITH TRANSIENT FUNCTIONS
WHY DOES CELL DEATH OCCUR IN VERTEBRATE NEURODEVELOPMENT?
ROHON-BEARD CELLS - LOSS IN ZEBRA FISH
Williams et al. Dev Biol (2000)
Chung et al. J Neurbiol (2000)
EX-MALES
M & EX-M+ TEST
BSTpr =Principal nucleus of the Bed nucleus of the striatus terminalis
SEXUALLY DIMORPHIC NEURON DEATH IN RAT BSTpr -REGULATION BY TESTOSTERONE
FEMALES
MALES
MALES
FEMALES
POST NATAL DAY
WHY DOES CELL DEATH OCCUR IN VERTEBRATE NEURODEVELOPMENT?
ELIMINATION OF NEURONS WITH ECTOPIC PROJECTIONS
WHY DOES CELL DEATH OCCUR IN VERTEBRATE NEURODEVELOPMENT?
“SYSTEMS MATCHING: CREATION OF OPTIMAL LEVELS OFINNERVATION BETWEEN INTERCONNECTED GROUPS OF NEURONS AND BETWEEN NEURONS AND THEIR NON-NEURONAL TARGETS” (Buss and Oppenheim Anat Sci Int, 2004)
WHAT HAPPENS IF DEVELOPMENTAL NEURON CELL DEATH IS ABSENT?
IN ABSENCE OF NORMAL DEVELOPMENTAL CELL DEATH MOST EXCESS NEURONS BECOME ATROPHIC:
EXAMPLE OF FACIAL NERVE
White et al. J Neurosci 1998
RETINAL NEURON RESPONSES TO LIGHT CHANGE IN ABSENCE OF NORMAL DEVELOPMENTAL CELL DEATH
GCL=ganglion cell layerINL=inner nuclear layerONL=outer nuclear layerIPL=inner plexiform layer
0
50
100
150
200
250
300
350
400
450
ROD TEST CONE TEST
WTBAX-/- mV
Relativenumber of responding neurons
(Péquignot et al. Dev Dyn 2003
WHY DOES CELL DEATH OCCUR IN VERTEBRATE NEURODEVELOPMENT?
PREVENT OVER-PRODUCTION OF NEUROPROGENITOR CELLS TO GENERATE PROPER SIZED BRAIN
WHY DOES CELL DEATH OCCUR IN NEURODEVELOPMENT?
ELIMINATION OF CELLS WITH DAMAGED DNA OR WITHOTHER DEFECTS
WHY DOES CELL DEATH OCCUR IN VERTEBRATE NEURODEVELOPMENT?
“A MEANS OF EVOLUTIONARY CHANGE: ADAPTIVECHANGES IN THE ONTOGENETIC DEATH AND SURVIVALOF CELLS IN REPSPONSE TO GENETIC MUTATION (E.G.THE PRODUCTION OF EXCESS NEURONS COULD BEUSED FOR THE INNERVATION OF NEW TARGETS MADEAVAILABLE BY THE EVOLUTION OF LIMBS)”
(Buss and Oppenheim Anat Sci Int, 2004)
WHAT ARE THE MECHANISMS BY WHICH NEURON SURVIVAL AND DEATH ARE REGULATED DURING
VERTEBRATE DEVELOPMENT?
TRKANGF
PI3K
AKT
RAS
ERK
SURVIVAL
WORTMANNINLY2942002D/N PI3K
D/N AKT
ACT-AKT
ACT-PI3K
ACT-RASD/N-RAS
PD98059U0126
DEATH IN SOMEPARADIGMS
TRK SIGNALING AND PROMOTION OF NEURON SURVIVAL
BADP- 14-3-3AKT (cytoplasmic)
FRKHP- 14-3-3AKT (cytoplasmic)
EXAMPLES OF HOW AKT PROMOTES SURVIVAL
IAP IAPAKTTRANSCRIPTIONAL
ACTIVATION
BAD
mitochondria DEATH
FRKH
nucleusBim DEATH
MITOCHONDRIA AND APOPTOTIC DEATH
CYTOCHROME C
mitochondrion BCL2BCL2
BAX BIM
BAX
BIM
BAX
BIM
BAX
BIM
APOPTOTIC STIMULI
BAKBAK
EGL1
CED9
CED4
CED3
CASPASE 9 ACTIVATION
APAF1 (APOPTOSOME)
CASPASE 3,6,7 ACTIVATION
0
5
10
15
20
25
30
35
VEHICLE CYCLOHEX ACT-D
% PYKNOTICCELLS IN
CERVICALSPINAL CORD
OF CHICKEMBRYO
DEVELOPMENTAL NEURON CELL DEATH IN VERTEBRATES REQUIRES MACROMOLECULAR SYNTHESIS
Plotted from data in: Yaginuma et al. J Neurosci 1996
TRANSCRIPTIONAL REGULATION OF APOPTOTIC DEATH
APOPTOTIC STIMULI
CASPASE 9 ACTIVATION
APAF1
CASPASE 3,6,7 ACTIVATION
CYTOCHROME C AIF
mitochondrionBCL2BCL2 BAXBIM
BAX
BIM
IAPs
SMAC/DIABLO
P53P63p73
cJun FKH E2F NFKB
AKT BLOCKS DEATH AT MULTIPLE LEVELS OF THE APOPTOTIC MECHANISM
APOPTOTIC STIMULI
CASPASE 9 ACTIVATION
APAF1
CASPASE 3,6,7 ACTIVATION
CYTOCHROME CAIF
mitochondrionBCL2BCL2 BAX
BIM
BAX
BIM
IAPs
SMAC
P53/P63/P73
cJun FKH E2F NFKB FAS
FAS-L
ELEVATE ANTI-APOPTOTIC MOLECULESBCLX-L
BLOCK APOPTOTIC TRANSC. PATHWAYS(FKH PHOSPHORYLATION)
BAD
PHOSPHORYLATE, EXCLUDE PRO-APOPTOTIC BAD
NEUROTROPHIC FACTORS/AKT
GDP
POSH
MLKMLK
PO4 PO4 PO4
JIP
MKK4/7JNK
PO4
JUNBIM
PO4
RAC1
APOPTOTIC STIMULI
GTP
DEATH SIGNALING BY THE JNK PATHWAY IN NEURON DEATH
Whitfield et al Neuron 2001
= d/n Jun
Bim
BIM IS UPREGULATED BY NGF DEPRIVATION, PARTLY VIA THE JNK PATHWAY AND CONTRIBUTES TO NEURON DEATH
JIP
GDP
POSH
MLK
MLK MKK4/7JNK
JUNBIM
RAC1
PROTEASOME
MLKS AND POSH ARE DEGRADED IN VIABLE NEURONS
APOPTOTIC STIMULI
JIPPOSH
MLKMLKMKK4/7
JNK
JUNBIM
RAC1
PROTEASOME
APOPTOTIC STIMULI
GTP
PO4PO4
PO4
PO4
MLKS AND POSH ARE STABILIZED BY A FEEDBACK LOOPMECHANISM IN RESPONSE TO APOPTOTIC STIMULI
JIPGTPPOSH
MLKMLK
PO4 PO4
MKK4/7
PO4
JNK
PO4
JUN
PO4
RAC1
APOPTOTIC STIMULI
PROTEASOME
DEATH SIGNALING BY THE JNK PATHWAY IN NEURON DEATH
BIMBIM
Neuronal PC12 cells
Hr -NGF 0 4 8
JNK
1 2 3
POSH
i ii
iii iv
v vi
JIP AND POSH RELOCALIZE IN RESPONSE TO APOPTOTIC STIMULI
CONTROL DNA DAMAGE
JIP
POSH
E2FRb
RbCHR MOD
TK
BLOCKED ACTIVATION
GENE REPRESSION
CDK4
CD1
PO4
PO4
TRANS-ACTIVATION
GENE DE-REPRESSION
S-PHASE
E2F C-MYB
E2F REGULATES CELL PROLIFERATION
E2F REGULATES CELL PROLIFERATION & NEURON DEATH
CDK4
CD1
S-PHASE
RbCHR MOD
GENE REPRESSION
PO4
GENE DE-REPRESSION
E2F1 C-MYB
p130CHR MOD
GENE REPRESSION
PO4
GENE DE-REPRESSION
E2F4 C-MYB
Antibody
p130
p107
pRb
Con
trol
-NGF
+NGF
C-MYB
C-MYB
p130 IS THE MAJOR E2F PARTER ON CHROMATIN IN NEURONS,IS PHOSPHORYLATED AND LOST WITH NGF DEPRIVATION, RESULTING IN MYB DE-REPRESSION AND UP-REGULATION
0 16 16+F
NGF W/D Hrs
SCG
p130
E2F REGULATES CELL PROLIFERATION & NEURON DEATH
CDK4
CD1
p130CHR MOD
GENE REPRESSION
PO4
GENE DE-REPRESSION
E2F4 C-MYB
A. Neuronal PC12 cells
GFP Bim merge
siBim
siB-myb
siC-myb
siCdk4
siLuc
THE E2F PATHWAY LEADS TO BIM UPREGULATION VIACDK4 AND MYB
E2F4 C-MYB
GENE REPRESSION
PO4
GENE DE-REPRESSION
p130SUVH39
HDAC
BIMC-MYB FOXOC-JUN
PO4
E2F AND NEURON CELL DEATH
APOPTOTIC STIMULI
CD1 CDK4CDK4
CD1
THE CDK4-E2F-p130-MYB-BIM PATHWAY OF NEURON CELL DEATH
E2F4p130
C-MYB
GENE REPRESSION
CDK4
CD1
PO4
GENE DE-REPRESSION
SUVH39
HDAC
BIMC-MYB FOXO
C-JUN
PO4APOPTOTIC STIMULI
TRANSCRIPTIONAL REGULATION OF APOPTOTIC DEATH
APOPTOTIC STIMULI
CASPASE 9 ACTIVATION
APAF1
CASPASE 3,6,7 ACTIVATION
CYTOCHROME C AIF
mitochondrionBCL2BCL2 BAXBIM
BAX
BIM
IAPs
SMAC/DIABLO
P53P63p73
cJun FKH E2F NFKB
• THERE IS MASSIVE DEATH OF NEURONS, NEUROPROGENITORS
AND OLIGODENDROGLIA IN NORMAL VERTEBRATE DEVELOPMENT
• THIS IS LARGELY REGULATED BY ACCESS TO LIMITING SUPPLIES OF EXOGENOUS SURVIVAL-PROMOTING TROPHIC FACTORS
• SURVIVAL IS PROMOTED LARGELY BY ACTIVATION OF AKT AS WELL ASOF ERKS AND INVOLVES BLOCKADE OF DEATH PATHWAYS AT MULTIPLE POINTS
• DEVELOPMENTAL NEURON DEATH IS TRANSCRIPTION DEPENDENT
• INDUCTION OF DEATH INVOLVES MULTIPLE PRO-APOTOTIC SIGNALING PATHWAYS, SOME OF WHICH CONVERGE ON INDUCTION OF BH3-DOMAIN PROTEINS