Defective CFTR induces aggresome formation and lung inflammation in cystic fibrosis through ROS-mediated autophagy inhibition.
Accumulation of unwanted/misfolded proteins in aggregates has been observed in airways of patients with cystic fibrosis (CF), a life-threatening genetic disorder caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). Here we show how the defective CFTR results in defective autophagy and decreases the clearance of aggresomes. Defective CFTR-induced upregulation of reactive oxygen species (ROS) and tissue transglutaminase (TG2) drive the crosslinking of beclin 1, leading to sequestration of phosphatidylinositol-3-kinase (PI(3)K) complex III and accumulation of p62, which regulates aggresome formation. Both CFTR knockdown and the overexpression of green fluorescent protein (GFP)-tagged-CFTR(F508del) induce beclin 1 downregulation and defective autophagy in non-CF airway epithelia through the ROS-TG2 pathway. Restoration of beclin 1 and autophagy by either beclin 1 overexpression, cystamine or antioxidants rescues the localization of the beclin 1 interactome to the endoplasmic reticulum and reverts the CF airway phenotype in vitro, in vivo in Scnn1b-transgenic and Cftr(F508del) homozygous mice, and in human CF nasal biopsies. Restoring beclin 1 or knocking down p62 rescued the trafficking of CFTR(F508del) to the cell surface. These data link the CFTR defect to autophagy deficiency, leading to the accumulation of protein aggregates and to lung inflammation.
Luciani
Alessandro
A
European Institute for Research in Cystic Fibrosis, San Raffaele Scientific Institute, Milan 20132, Italy.
Villella
Valeria Rachela
VR
Esposito
Speranza
S
Brunetti-Pierri
Nicola
N
Medina
Diego
D
Settembre
Carmine
C
Gavina
Manuela
M
Pulze
Laura
L
Giardino
Ida
I
Pettoello-Mantovani
Massimo
M
D'Apolito
Maria
M
Guido
Stefano
S
Masliah
Eliezer
E
Spencer
Brian
B
Quaratino
Sonia
S
Raia
Valeria
V
Ballabio
Andrea
A
Maiuri
Luigi
L
D000111:Acetylcysteine / Q000494:pharmacology / Q000627:therapeutic use; D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology / Q000627:therapeutic use; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism; D001343:Autophagy / Q000187:drug effects / Q000235:genetics; D000071186:Beclin-1; D002460:Cell Line; D003538:Cystamine / Q000494:pharmacology / Q000627:therapeutic use; D003550:Cystic Fibrosis / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D053503:Epithelial Sodium Channels / Q000235:genetics; D019204:GTP-Binding Proteins; D006360:Heat-Shock Proteins / Q000378:metabolism; D006801:Humans; D007249:Inflammation / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D018181:Mice, Inbred CFTR; D008815:Mice, Inbred Strains; D008822:Mice, Transgenic; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D008954:Models, Biological; D009298:Nasal Polyps / Q000188:drug therapy / Q000378:metabolism; D009942:Organometallic Compounds / Q000494:pharmacology; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D011485:Protein Binding / Q000502:physiology; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D021381:Protein Transport / Q000235:genetics; D017382:Reactive Oxygen Species / Q000037:antagonists & inhibitors / Q000378:metabolism*; D020545:Respiratory Mucosa / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D012459:Salicylates / Q000494:pharmacology; D000071456:Sequestosome-1 Protein; D025841:Small Ubiquitin-Related Modifier Proteins / Q000378:metabolism; D011503:Transglutaminases / Q000235:genetics / Q000378:metabolism; D055815:Young Adult
D000111:Acetylcysteine; D048868:Adaptor Proteins, Signal Transducing; D000975:Antioxidants; D051017:Apoptosis Regulatory Proteins; D000071186:Beclin-1; D003538:Cystamine; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D053503:Epithelial Sodium Channels; D019204:GTP-Binding Proteins; D006360:Heat-Shock Proteins; D008565:Membrane Proteins; D008869:Microtubule-Associated Proteins; D009942:Organometallic Compounds; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D017382:Reactive Oxygen Species; D012459:Salicylates; D000071456:Sequestosome-1 Protein; D025841:Small Ubiquitin-Related Modifier Proteins; D011503:Transglutaminases; C491997:BECN1 protein, human; C115010:Becn1 protein, mouse; C433928:EUK-134; C477012:MAP1LC3A protein, human; C480860:Map1lc3b protein, mouse; C099718:SQSTM1 protein, human; C507049:Scnn1b protein, mouse; C101343:Sqstm1 protein, mouse