Intronic GGGGCC (G4C2) hexanucleotide repeat expansion within the human C9orf72 gene represents the most common cause of familial forms of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (C9ALS/FTD). Repeat-associated non-AUG (RAN) translation of repeat-containing C9orf72 RNA results in the production of neurotoxic dipeptide-repeat proteins (DPRs). Here, we developed a high-throughput drug screen for the identification of positive and negative modulators of DPR levels. We found that HSP90 inhibitor geldanamycin and aldosterone antagonist spironolactone reduced DPR levels by promoting protein degradation via the proteasome and autophagy pathways respectively. Surprisingly, cAMP-elevating compounds boosting protein kinase A (PKA) activity increased DPR levels. Inhibition of PKA activity, by both pharmacological and genetic approaches, reduced DPR levels in cells and rescued pathological phenotypes in a Drosophila model of C9ALS/FTD. Moreover, knockdown of PKA-catalytic subunits correlated with reduced translation efficiency of DPRs, while the PKA inhibitor H89 reduced endogenous DPR levels in C9ALS/FTD patient-derived iPSC motor neurons. Together, our results suggest new and druggable pathways modulating DPR levels in C9ALS/FTD.

C9orf72 ALS/FTD dipeptide repeat protein levels are reduced by small molecules that inhibit PKA or enhance protein degradation / Licata, Nausicaa V; Cristofani, Riccardo; Salomonsson, Sally; Wilson, Katherine M; Kempthorne, Liam; Vaizoglu, Deniz; D’Agostino, Vito; Pollini, Daniele; Loffredo, Rosa; Pancher, Michael; Adami, Valentina; Bellosta, Paola; Ratti, Antonia; Viero, Gabriella; Quattrone, Alessandro; Isaacs, Adrian M; Poletti, Angelo; Provenzani, Alessandro. - In: EMBO JOURNAL. - ISSN 0261-4189. - 2021:(2021), pp. e10502601-e10502623. [10.15252/embj.2020105026]

C9orf72 ALS/FTD dipeptide repeat protein levels are reduced by small molecules that inhibit PKA or enhance protein degradation

Licata, Nausicaa V;D’Agostino, Vito;Pollini, Daniele;Loffredo, Rosa;Pancher, Michael;Adami, Valentina;Bellosta, Paola;Quattrone, Alessandro;Provenzani, Alessandro
2021-01-01

Abstract

Intronic GGGGCC (G4C2) hexanucleotide repeat expansion within the human C9orf72 gene represents the most common cause of familial forms of amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) (C9ALS/FTD). Repeat-associated non-AUG (RAN) translation of repeat-containing C9orf72 RNA results in the production of neurotoxic dipeptide-repeat proteins (DPRs). Here, we developed a high-throughput drug screen for the identification of positive and negative modulators of DPR levels. We found that HSP90 inhibitor geldanamycin and aldosterone antagonist spironolactone reduced DPR levels by promoting protein degradation via the proteasome and autophagy pathways respectively. Surprisingly, cAMP-elevating compounds boosting protein kinase A (PKA) activity increased DPR levels. Inhibition of PKA activity, by both pharmacological and genetic approaches, reduced DPR levels in cells and rescued pathological phenotypes in a Drosophila model of C9ALS/FTD. Moreover, knockdown of PKA-catalytic subunits correlated with reduced translation efficiency of DPRs, while the PKA inhibitor H89 reduced endogenous DPR levels in C9ALS/FTD patient-derived iPSC motor neurons. Together, our results suggest new and druggable pathways modulating DPR levels in C9ALS/FTD.
2021
Licata, Nausicaa V; Cristofani, Riccardo; Salomonsson, Sally; Wilson, Katherine M; Kempthorne, Liam; Vaizoglu, Deniz; D’Agostino, Vito; Pollini, Daniele; Loffredo, Rosa; Pancher, Michael; Adami, Valentina; Bellosta, Paola; Ratti, Antonia; Viero, Gabriella; Quattrone, Alessandro; Isaacs, Adrian M; Poletti, Angelo; Provenzani, Alessandro
C9orf72 ALS/FTD dipeptide repeat protein levels are reduced by small molecules that inhibit PKA or enhance protein degradation / Licata, Nausicaa V; Cristofani, Riccardo; Salomonsson, Sally; Wilson, Katherine M; Kempthorne, Liam; Vaizoglu, Deniz; D’Agostino, Vito; Pollini, Daniele; Loffredo, Rosa; Pancher, Michael; Adami, Valentina; Bellosta, Paola; Ratti, Antonia; Viero, Gabriella; Quattrone, Alessandro; Isaacs, Adrian M; Poletti, Angelo; Provenzani, Alessandro. - In: EMBO JOURNAL. - ISSN 0261-4189. - 2021:(2021), pp. e10502601-e10502623. [10.15252/embj.2020105026]
File in questo prodotto:
File Dimensione Formato  
EMBOJ-2020-105026_Merged_PDF.pdf

accesso aperto

Tipologia: Pre-print non referato (Non-refereed preprint)
Licenza: Altra licenza (Other type of license)
Dimensione 2.61 MB
Formato Adobe PDF
2.61 MB Adobe PDF Visualizza/Apri
embj.2020105026.pdf

accesso aperto

Tipologia: Versione editoriale (Publisher’s layout)
Licenza: Creative commons
Dimensione 5.11 MB
Formato Adobe PDF
5.11 MB Adobe PDF Visualizza/Apri

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11572/323036
Citazioni
  • ???jsp.display-item.citation.pmc??? 2
  • Scopus 12
  • ???jsp.display-item.citation.isi??? 10
social impact