Abstract
In immunoglobulin (Ig) light-chain (LC) (AL) amyloidosis, AL deposition translates into lifethreatening cardiomyopathy. Clinical and experimental evidence indicates that soluble cardiotoxic LCs are themselves harmful for cells, by which they are internalized. Hypothesizing that interaction of soluble cardiotoxic LCs with cellular proteins contributes to damage, we characterized their interactome in cardiac cells. LCs were purified from patients with AL amyloidosis cardiomyopathy or multiplemyeloma without amyloidosis (the nonamyloidogenic/ noncardiotoxic LCs served as controls) and employed at concentrations in the range observed in AL patients' sera. A functional proteomic approach, based on direct and inverse coimmunoprecipitation and mass spectrometry, allowed identifying LC-protein complexes. Findings were validated by colocalization, fluorescence lifetime imaging microscopy (FLIM)-fluorescence resonance energy transfer (FRET), and ultrastructural studies, using human primary cardiac fibroblasts (hCFs) and stem cell-derived cardiomyocytes. Amyloidogenic cardiotoxic LCs interact in vitro with specific intracellular proteins involved in viability and metabolism. Imaging confirmed that, especially in hCFs, cardiotoxic LCs (not controls) colocalize with mitochondria and spatially associate with selected interactors: mitochondrial optic atrophy 1-like protein and peroxisomal acyl-coenzyme A oxidase 1 (FLIM-FRET efficiencies 11 and 6%, respectively). Cardiotoxic LC-treated hCFs display mitochondrial ultrastructural changes, supporting mitochondrial involvement. We show that cardiotoxic LCs establish nonphysiologic protein-protein contacts in human cardiac cells, offering new clues on the pathogenesis of AL cardiomyopathy.
| Original language | English |
|---|---|
| Pages (from-to) | 4614-4628 |
| Number of pages | 15 |
| Journal | FASEB Journal |
| Volume | 29 |
| Issue number | 11 |
| DOIs | |
| Publication status | Published - Nov 1 2015 |
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Keywords
- Functional proteomics
- Human cardiac cells
- Protein-misfolding diseases
- Protein-protein interaction
- Proteotoxicity
ASJC Scopus subject areas
- Biochemistry
- Biotechnology
- Genetics
- Molecular Biology
- Medicine(all)
Cite this
Novel mitochondrial protein interactors of immunoglobulin light chains causing heart amyloidosis. / Lavatelli, Francesca; Imperlini, Esther; Orrù, Stefania; Rognoni, Paola; Sarnataro, Daniela; Palladini, Giuseppina; Malpasso, Giuseppe; Soriano, Maria Eugenia; Di Fonzo, Andrea; Valentini, Veronica; Gnecchi, Massimiliano; Perlini, Stefano; Salvatore, Francesco; Merlini, Giampaolo.
In: FASEB Journal, Vol. 29, No. 11, 01.11.2015, p. 4614-4628.Research output: Contribution to journal › Article
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TY - JOUR
T1 - Novel mitochondrial protein interactors of immunoglobulin light chains causing heart amyloidosis
AU - Lavatelli, Francesca
AU - Imperlini, Esther
AU - Orrù, Stefania
AU - Rognoni, Paola
AU - Sarnataro, Daniela
AU - Palladini, Giuseppina
AU - Malpasso, Giuseppe
AU - Soriano, Maria Eugenia
AU - Di Fonzo, Andrea
AU - Valentini, Veronica
AU - Gnecchi, Massimiliano
AU - Perlini, Stefano
AU - Salvatore, Francesco
AU - Merlini, Giampaolo
PY - 2015/11/1
Y1 - 2015/11/1
N2 - In immunoglobulin (Ig) light-chain (LC) (AL) amyloidosis, AL deposition translates into lifethreatening cardiomyopathy. Clinical and experimental evidence indicates that soluble cardiotoxic LCs are themselves harmful for cells, by which they are internalized. Hypothesizing that interaction of soluble cardiotoxic LCs with cellular proteins contributes to damage, we characterized their interactome in cardiac cells. LCs were purified from patients with AL amyloidosis cardiomyopathy or multiplemyeloma without amyloidosis (the nonamyloidogenic/ noncardiotoxic LCs served as controls) and employed at concentrations in the range observed in AL patients' sera. A functional proteomic approach, based on direct and inverse coimmunoprecipitation and mass spectrometry, allowed identifying LC-protein complexes. Findings were validated by colocalization, fluorescence lifetime imaging microscopy (FLIM)-fluorescence resonance energy transfer (FRET), and ultrastructural studies, using human primary cardiac fibroblasts (hCFs) and stem cell-derived cardiomyocytes. Amyloidogenic cardiotoxic LCs interact in vitro with specific intracellular proteins involved in viability and metabolism. Imaging confirmed that, especially in hCFs, cardiotoxic LCs (not controls) colocalize with mitochondria and spatially associate with selected interactors: mitochondrial optic atrophy 1-like protein and peroxisomal acyl-coenzyme A oxidase 1 (FLIM-FRET efficiencies 11 and 6%, respectively). Cardiotoxic LC-treated hCFs display mitochondrial ultrastructural changes, supporting mitochondrial involvement. We show that cardiotoxic LCs establish nonphysiologic protein-protein contacts in human cardiac cells, offering new clues on the pathogenesis of AL cardiomyopathy.
AB - In immunoglobulin (Ig) light-chain (LC) (AL) amyloidosis, AL deposition translates into lifethreatening cardiomyopathy. Clinical and experimental evidence indicates that soluble cardiotoxic LCs are themselves harmful for cells, by which they are internalized. Hypothesizing that interaction of soluble cardiotoxic LCs with cellular proteins contributes to damage, we characterized their interactome in cardiac cells. LCs were purified from patients with AL amyloidosis cardiomyopathy or multiplemyeloma without amyloidosis (the nonamyloidogenic/ noncardiotoxic LCs served as controls) and employed at concentrations in the range observed in AL patients' sera. A functional proteomic approach, based on direct and inverse coimmunoprecipitation and mass spectrometry, allowed identifying LC-protein complexes. Findings were validated by colocalization, fluorescence lifetime imaging microscopy (FLIM)-fluorescence resonance energy transfer (FRET), and ultrastructural studies, using human primary cardiac fibroblasts (hCFs) and stem cell-derived cardiomyocytes. Amyloidogenic cardiotoxic LCs interact in vitro with specific intracellular proteins involved in viability and metabolism. Imaging confirmed that, especially in hCFs, cardiotoxic LCs (not controls) colocalize with mitochondria and spatially associate with selected interactors: mitochondrial optic atrophy 1-like protein and peroxisomal acyl-coenzyme A oxidase 1 (FLIM-FRET efficiencies 11 and 6%, respectively). Cardiotoxic LC-treated hCFs display mitochondrial ultrastructural changes, supporting mitochondrial involvement. We show that cardiotoxic LCs establish nonphysiologic protein-protein contacts in human cardiac cells, offering new clues on the pathogenesis of AL cardiomyopathy.
KW - Functional proteomics
KW - Human cardiac cells
KW - Protein-misfolding diseases
KW - Protein-protein interaction
KW - Proteotoxicity
UR - http://www.scopus.com/inward/record.url?scp=84948808896&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84948808896&partnerID=8YFLogxK
U2 - 10.1096/fj.15-272179
DO - 10.1096/fj.15-272179
M3 - Article
C2 - 26220173
AN - SCOPUS:84948808896
VL - 29
SP - 4614
EP - 4628
JO - FASEB Journal
JF - FASEB Journal
SN - 0892-6638
IS - 11
ER -