ER stress video abstract v2

Protein misfolding is a prominent feature in amyotrophic lateral sclerosis (ALS)

TDP-43 Ubiquitin

FUS/TLS Ubiquitin

p

ATF6IRE1a

RNase

Misfoldedproteins

PERK Kinase

Protein misfolding activates endoplasmic reticulum (ER) stress

p

ATF6IRE1a

RNase

Pre-Xbp1 RNA Mature Xbp1 mRNA

Misfoldedproteins

PERK Kinase

Protein misfolding activates endoplasmic reticulum (ER) stress

miRNAProtein quality control

p

ATF6IRE1a

RNase

Pre-Xbp1 RNA Mature Xbp1 mRNA

Misfoldedproteins

PERK Kinase

Protein misfolding activates endoplasmic reticulum (ER) stress

?ASK1 p

NeuronalDeathpJNK

Homeodomain interacting protein kinase 2 (HIPK2)

Brn3a, Nkx, Pax6Smad1/2/3, c-Skic-myb, NLK, p53p300, Runx1 (AML1)

Protein-proteininteraction domainS/T/Y kinase domain

SRS 1189 a.a.HIPK2NLS

CtBP/-catenin(Corepressor domain)

(SUMO)K25

(Ubi)K1182PEST

Cellular response to DNA damage

Vascular development

Neuronal survival & cell death

Wiggins et al., J Cell Biol 2004Zhang et al., Nature Neurosci 2007Wei et al., PNAS 2007Chalazonitis et al., J Neurosci 2012

p

ATF6IRE1a

RNase

Pre-Xbp1 RNA Mature Xbp1 mRNA

Misfoldedproteins

PERK Kinase

Protein misfolding activates endoplasmic reticulum (ER) stress

NeuronalDeath

HIPK2 knockoutfibroblasts & neurons

Tunicamycin

Biochemical approaches reveal epitope-specific HIPK2 activation during ER stress

1 192 520 583 897 1189

Kinase domain

S359 T360 Y361

P P

ASK1 PP

1

2

2

HIPK2Interactiondomain

ER Stress & IRE1α activation

1 192 520 583 897 1189

Kinase domain

S359 T360 Y361

P P

Activation ofHIPK2 kinase

ASK1 PP

1

2

2

3HIPK2Interaction

domain

ER Stress & IRE1α activation

1 192 520 583 897 1189

Kinase domain

S359 T360 Y361

583 798

P P

Activation ofHIPK2 kinase

JNK PP

ASK1 PP

1

2

2

34

HIPK2Interactiondomain

ER Stress & IRE1α activation

Loss of HIPK2 delays disease onset and prolongs survival in SOD1G93A mice

Distinct role of HIPK2 & ER stress pathway in different ALS models

ALS-FUS-R521CDendrite/Synaptic

defectsBDNF/TrkB SignalingTranscription & RNA

splicingDNA damage repairNeuroinflammation

ALS-SOD1G93A

ER Stress/UPRCell Death

Oligodendroglia Defects

Axonal TransportMitochondrial

DefectsNeuroinflammation

ALS-hTDPDNLS

ER Stress/UPRTranscription &

RNA SplicingNucleosome

AssemblyCell Death

Distinct role of HIPK2 & ER stress pathway in different ALS models

ALS-FUS-R521CDendrite/Synaptic

defectsBDNF/TrkB SignalingTranscription & RNA

splicingDNA damage repairNeuroinflammation

ALS-SOD1G93A

ER Stress/UPRCell Death

Oligodendroglia Defects

Axonal TransportMitochondrial

DefectsNeuroinflammation

ALS-hTDPDNLS

ER Stress/UPRTranscription &

RNA SplicingNucleosome

AssemblyCell Death

✗✔ ✔

Sporadic ALS (TDP proteinopathy)

ER stress/UPRHIPK2 and JNK activation

Neurodegeneration

Misfolded proteins in FALS and SALS activate HIPK2 in ER stress pathway

ALS-C9orf72

ER Stress/UPRDipeptide repeat

toxicityRNA toxicity

Nuclear pore defectLOF in C9orf72

Microglial activation

ALS-FUS-R521CDendrite/Synaptic

defectsBDNF/TrkB SignalingTranscription & RNA

splicingDNA damage repairNeuroinflammation

ALS-SOD1G93A

ER Stress/UPRCell Death

Oligodendroglia Defects

Axonal TransportMitochondrial

DefectsNeuroinflammation

ALS-hTDPDNLS

ER Stress/UPRTranscription &

RNA SplicingNucleosome

AssemblyCell Death

✗✔ ✔

HIPK2 activation positively correlates with TDP-43 proteinopathy in C9-ALS and SALS

p

p

ATF6IRE1a

RNase

Pre-Xbp1 RNA Mature Xbp1 mRNA

Misfoldedproteins

PERK Kinase

HIPK2JNK

ASK1 p

pp

NeuronalDeath

GlialToxicity

Protein misfolding activates endoplasmic reticulum (ER) stress

TunicamycinTg-SOD1G93A

Tg-hTDP-43ΔNLSSALS/C9-ALS

** Special thanks to Claire Huang for video/audio production & editing

Modeling of HIPK2 kinase domain reveals epitope activated during ER stress

ER Stress & IRE1α activation

ASK1 PP

1