Inhibition by small-molecule ligands of formation of amyloid fibrils of an immunoglobulin light chain variable domain

Brumshtein, Boris; Esswein, Shannon R.; Salwiński, Łukasz; Phillips, Martin; Ly, Alan T.; Cascio, Duilio; Sawaya, M.R.; Eisenberg, David

doi:10.7554/elife.10935

Cited by 57 publications

(44 citation statements)

References 51 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…S9). This binding site is consistent with previous reports that the interface between V domains in the dimer can accommodate various aromatic ligands (21,42), although the exact binding site that we identify below has not been previously observed. The binding site for 1 comprises residues P44, Y87, and F98 from one protomer and Y36ʹ, P44ʹ, and T46ʹ from the other protomer ( Fig.…”

Section: -Amino-coumarins Are Fluorogenic Kinetic Stabilizers Of λ6asupporting

confidence: 92%

“…Edmundson et al (42) identified regions within the interface between the V domains of an amyloidogenic FL LC, known as MCG, that could bind hydrophobic ligands. Brumshtein et al (21) reported small molecules that bind to the MCG-V domain and prevent its aggregation (21). However, neither of the small molecules for which cocrystal structures were solved (sulfasalazine and methylene blue) were active in our PCFP assay employing WIL-FL* (SI Appendix, Fig.…”

Section: Discussionmentioning

confidence: 96%

“…We refer to such molecules as kinetic stabilizers, since they reduce the rate at which LCs transiently visit nonnative, aggregation-prone, and protease-sensitive conformations (20). The interfaces between the domains of the LC dimer are an important determinant of stability and aggregation propensity that we and others have identified as potential targets for stabilization (21,22). We therefore seek treatments that prevent newly synthesized and secreted FL LCs from misfolding and aggregating, thus reducing organ proteotoxicity, such that patients can eventually tolerate effective chemotherapy regimens.Using a protease-coupled fluorescence polarization (PCFP) assay that assesses LC kinetic stability, we screened 650,000 small molecules and identified FL LC kinetic stabilizers in four structural classes that protect recombinant and plasma cell-secreted λ6a LCs from endoproteolysis.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Stabilization of amyloidogenic immunoglobulin light chains by small molecules

Morgan

Yan

Mortenson

et al. 2019

Proc. Natl. Acad. Sci. U.S.A.

114

View full text Add to dashboard Cite

In Ig light-chain (LC) amyloidosis (AL), the unique antibody LC protein that is secreted by monoclonal plasma cells in each patient misfolds and/or aggregates, a process leading to organ degeneration. As a step toward developing treatments for AL patients with substantial cardiac involvement who have difficulty tolerating existing chemotherapy regimens, we introduce small-molecule kinetic stabilizers of the native dimeric structure of full-length LCs, which can slow or stop the amyloidogenicity cascade at its origin. A protease-coupled fluorescence polarization-based high-throughput screen was employed to identify small molecules that kinetically stabilize LCs. NMR and X-ray crystallographic data demonstrate that at least one structural family of hits bind at the LC-LC dimerization interface within full-length LCs, utilizing variable-domain residues that are highly conserved in most AL patients. Stopping the amyloidogenesis cascade at the beginning is a proven strategy to ameliorate postmitotic tissue degeneration.kinetic stabilizer | high-throughput screen | dimerization | structural biology | proteotoxicity S ecretion of an Ig light chain (LC) by a clonally expanded plasma cell population can lead to the disease LC amyloidosis (AL)-both a cancer and a proteinopathy (1, 2). "Free" LCs secreted without an associated antibody heavy chain (HC) initially adopt a well-defined homodimeric structure, wherein the monomers may be covalently linked by an interchain disulfide bond ( Fig. 1A) (3). LC monomers comprise an N-terminal variable (V) domain attached to a C-terminal constant (C) domain (SI Appendix, Fig. S1). Each patient's clonal plasma cells secrete a single, unique LC sequence. Most LCs are rapidly removed by the kidney.However, since amyloidogenic full-length (FL) LCs are generally less stable than nonamyloidogenic FL LCs, they can misfold, or misfold and misassemble, into nonnative species including cross-β-sheet amyloid fibrils, which are a hallmark of AL (4-8). Sequence also seems to play a role, as not all destabilized FL LCs aggregate in patients (4-8). How aggregation occurs in patients is not known, but several processes have been described in vitro, including destabilization-dependent endoproteolysis that releases amyloidogenic LC fragments (4,9,10). LC fragments including V domains are observed in patient deposits alongside FL LCs (11-13).Since we do not understand the structure-proteotoxicity relationships driving AL, a conservative strategy is to block FL LC misfolding at its origin by stabilizing the FL LC native state. Such a strategy has been effective at ameliorating the transthyretin amyloidoses (14-19). A small molecule that stabilizes FL LC dimers should prevent any misfolding and/or endoproteolysis that lead to LC aggregation and organ toxicity. We refer to such molecules as kinetic stabilizers, since they reduce the rate at which LCs transiently visit nonnative, aggregation-prone, and protease-sensitive conformations (20). The interfaces between the domains of the LC dimer are an important...

show abstract

Section: -Amino-coumarins Are Fluorogenic Kinetic Stabilizers Of λ6asupporting

confidence: 92%

Section: Discussionmentioning

confidence: 96%

mentioning

confidence: 99%

See 1 more Smart Citation

Stabilization of amyloidogenic immunoglobulin light chains by small molecules

Morgan

Yan

Mortenson

et al. 2019

Proc. Natl. Acad. Sci. U.S.A.

114

View full text Add to dashboard Cite

show abstract

“…This model is also supported by data from a recent drug screen (66). We found that ϳ50% of LC in urine existed as disulfidecross-linked dimers, and all LC existed as di-or multimers under native conditions.…”

Section: Discussionsupporting

confidence: 80%

“…This suggests that treatment with anti-amyloid drugs that either stabilize the native LC dimer or inhibit amyloid formation may be a promising supplemental therapeutic strategy to ameliorate the amyloid pathology in AL patients. It would therefore be valuable to assess the potential of drugs, such as EGCG, methylene blue, and Orcein/ O4, which have proven effective in inhibiting amyloid formation in other disease-related proteins, for the treatment of AL amyloidosis (32,66,86).…”

Section: Discussionmentioning

confidence: 99%

Aggregation of Full-length Immunoglobulin Light Chains from Systemic Light Chain Amyloidosis (AL) Patients Is Remodeled by Epigallocatechin-3-gallate

Andrich

Hegenbart

Kimmich

et al. 2017

Journal of Biological Chemistry

View full text Add to dashboard Cite

Edited by Paul E. FraserIntervention into amyloid deposition with anti-amyloid agents like the polyphenol epigallocatechin-3-gallate (EGCG) is emerging as an experimental secondary treatment strategy in systemic light chain amyloidosis (AL). In both AL and multiple myeloma (MM), soluble immunoglobulin light chains (LC) are produced by clonal plasma cells, but only in AL do they form amyloid deposits in vivo. We investigated the amyloid formation of patient-derived LC and their susceptibility to EGCG in vitro to probe commonalities and systematic differences in their assembly mechanisms. We isolated nine LC from the urine of AL and MM patients. We quantified their thermodynamic stabilities and monitored their aggregation under physiological conditions by thioflavin T fluorescence, light scattering, SDS stability, and atomic force microscopy. LC from all patients formed amyloid-like aggregates, albeit with individually different kinetics. LC existed as dimers, ϳ50% of which were linked by disulfide bridges. Our results suggest that cleavage into LC monomers is required for efficient amyloid formation. The kinetics of AL LC displayed a transition point in concentration dependence, which MM LC lacked. The lack of concentration dependence of MM LC aggregation kinetics suggests that conformational change of the light chain is rate-limiting for these proteins. Aggregation kinetics displayed two distinct phases, which corresponded to the formation of oligomers and amyloid fibrils, respectively. EGCG specifically inhibited the second aggregation phase and induced the formation of SDS-stable, non-amyloid LC aggregates. Our data suggest that EGCG intervention does not depend on the individual LC sequence and is similar to the mechanism observed for amyloid-␤ and ␣-synuclein. Systemic light chain amyloidosis (AL)2 is the most common form of systemic amyloidosis (1), but it is still a rare disease with an incidence of 6 -7 in 1,000,000 people (2). Underlying AL pathology is a clonal plasma cell disorder, which produces an immunoglobulin light chain in the bone marrow with a unique sequence. These light chains are released into the blood (monoclonal gammopathy). When elevated LC levels in serum overwhelm renal absorption, LC is also found in the urine. Fulllength LC can be isolated from the urine of these patients (3-5).Clonal plasma cell disorders can present different types of pathologies; light chains form amyloid deposits in AL patients. Here, LC fibrils adopt a conformation characterized by highly stable, intramolecular cross-␤-sheets that stain with Congo red (6) and thioflavin T (ThT) (7-9).In contrast, amyloid deposits are not observed in patients suffering from multiple myeloma (MM), a malignant disease characterized by bone marrow failure and bone destruction. The two contrasting pathologies of LC gammopathies raise the question of which factors determine amyloid formation. Amyloid formation could be initiated (a) by the sequences of the individual light chains, (b) by high levels of light chain expression, (c) by p...

show abstract

Native State Stabilization of Amyloidogenic Proteins by Kinetic Stabilizers: Inhibition of Protein Aggregation and Clinical Relevance

Priyanka,

Raymandal,

Mondal

2024

ChemMedChem

View full text Add to dashboard Cite

Proteinopathies or amyloidoses are a group of life‐threatening disorders that result from misfolding of proteins and aggregation into toxic insoluble amyloid aggregates. Amyloid aggregates have low clearance from the body due to the insoluble nature, leading to their deposition in various organs and consequent organ dysfunction. While amyloid deposition in the central nervous system leads to neurodegenerative diseases that mostly cause dementia and difficulty in movement, several other organs, including heart, liver and kidney are also affected by systemic amyloidoses. Regardless of the site of amyloid deposition, misfolding and structural alteration of the precursor proteins play the central role in amyloid formation. Kinetic stabilizers are an emerging class of drugs, which act like pharmacological chaperones to stabilize the native state structure of amyloidogenic proteins and to increase the activation energy barrier that is required for adopting a misfolded structure or conformation, ultimately leading to the inhibition of protein aggregation. In this review, we discuss the kinetic stabilizers that stabilize the native quaternary structure of transthyretin, immunoglobulin light chain and superoxide dismutase 1 that cause transthyretin amyloidoses, light chain amyloidosis and familial amyotrophic lateral sclerosis, respectively.

show abstract

Inhibition by small-molecule ligands of formation of amyloid fibrils of an immunoglobulin light chain variable domain

Cited by 57 publications

References 51 publications

Stabilization of amyloidogenic immunoglobulin light chains by small molecules

Stabilization of amyloidogenic immunoglobulin light chains by small molecules

Aggregation of Full-length Immunoglobulin Light Chains from Systemic Light Chain Amyloidosis (AL) Patients Is Remodeled by Epigallocatechin-3-gallate

Native State Stabilization of Amyloidogenic Proteins by Kinetic Stabilizers: Inhibition of Protein Aggregation and Clinical Relevance

Contact Info

Product

Resources

About