Wild-type Human γD-crystallin Promotes Aggregation of Its Oxidation-mimicking, Misfolding-prone W42Q Mutant

Serebryany, Eugene; King, Jonathan

doi:10.1074/jbc.m114.621581

Cited by 37 publications

(89 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…DSC ( Figure 1C) revealed that there was almost no difference in the temperature of the two mutants' unfolding transitions. The available chemical denaturation curves confirm similar stability of W42Q and W42R (39,51). Table 1 summarizes melting temperatures obtained from DSC of the WT and several mutant constructs.…”

Section: W42r and W42q Are Similar To Each Other In Stability And Aggmentioning

confidence: 85%

“…We have previously reported that the aggregates formed by the temperature-sensitive Trp mutants of γD-crystallin under near-physiological conditions are neither disulfide-bridged nor amyloid and expose few hydrophobic residues (39,50). These observations raised the question of whether a seeding effect exists in this aggregation pathway.…”

Section: W42r and W42q Aggregation Occurs At Solution Redox Potentialmentioning

confidence: 94%

“…Whole-protein mass spectrometry experiments (39) revealed that most monomers within the aggregated fraction contain only one disulfide bond. HγD contains six Cys residues (Figure 1A), so we set out to determine whether a particular internal disulfide is most likely to generate intermolecular interactions that could lead to a polymeric state.…”

Section: Two-chain Tethered Simulations Predict Internaldisulfide Strmentioning

confidence: 99%

“…We and others have demonstrated that γ-crystallins, too, form crucial disulfide-mediated interactions. Thus, aggregation of W42Q γD-crystallin depends on internal disulfide bonds (39), and so do the folding kinetics and protease sensitivity of γB-crystallin (40). Although the crystallins are cytosolic, and therefore initially fold in a reducing environment, the redox potential of lens cytosol shifts toward increasingly oxidizing values during the course of aging and, especially, cataractogenesis (41).…”

mentioning

confidence: 99%

See 3 more Smart Citations

An Internal Disulfide Locks a Misfolded Aggregation-Prone Intermediate in Cataract-Linked Mutants of Human Gamma-D Crystallin

Serebryany

Woodard

Adkar

et al. 2017

Biophysical Journal

Self Cite

View full text Add to dashboard Cite

Considerable mechanistic insight has been gained into amyloid aggregation; however, a large class of non-amyloid protein aggregates are considered "amorphous," and in most cases little is known about their mechanisms. Amorphous aggregation of γ-crystallins in the eye lens causes a widespread disease of aging, cataract. We combined simulations and experiments to study the mechanism of aggregation of two γD-crystallin mutants, W42R and W42Q -the former a congenital cataract mutation, and the latter a mimic of age-related oxidative damage. We found that formation of an internal disulfide was necessary and sufficient for aggregation under physiological conditions. Twochain all-atom simulations predicted that one nonnative disulfide in particular, between Cys32 and Cys41, was likely to stabilize an unfolding intermediate prone to intermolecular interactions. Mass spectrometry and mutagenesis experiments confirmed the presence of this bond in the aggregates and its necessity for oxidative aggregation under physiological conditions in vitro. Mining the simulation data linked formation of this disulfide to extrusion of the N-terminal β-hairpin and rearrangement of the native β-sheet topology.

show abstract

Section: W42r and W42q Are Similar To Each Other In Stability And Aggmentioning

confidence: 85%

Section: W42r and W42q Aggregation Occurs At Solution Redox Potentialmentioning

confidence: 94%

Section: Two-chain Tethered Simulations Predict Internaldisulfide Strmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

An Internal Disulfide Locks a Misfolded Aggregation-Prone Intermediate in Cataract-Linked Mutants of Human Gamma-D Crystallin

Serebryany

Woodard

Adkar

et al. 2017

Biophysical Journal

Self Cite

View full text Add to dashboard Cite

show abstract

“…Similarly, high levels of oxidation of αB-crystallin Met-68 have been reported in cataractous lenses (Yanshole et al 2013). The oxidation-mimicking W42Q mutant of γD-crystallin readily shows reduced thermal stability and aggregates in the presence of WT γD-crystallin (Serebryany and King 2015). Likewise, the presence of oxidised βA3-crystallin peptide (152-166) increases aggregation in both α-and γ-crystallin bovine lens fractions (Udupa and Sharma 2005).…”

Section: Oxidationmentioning

confidence: 99%

Biophysical chemistry of the ageing eye lens

Ray

2015

Biophys Rev

View full text Add to dashboard Cite

This review examines both recent and historical literature related to the biophysical chemistry of the proteins in the ageing eye, with a particular focus on cataract development. The lens is a vital component of the eye, acting as an optical focusing device to form clear images on the retina. The lens maintains the necessary high transparency and refractive index by expressing crystallin proteins in high concentration and eliminating all large cellular structures that may cause light scattering. This has the consequence of eliminating lens fibre cell metabolism and results in mature lens fibre cells having no mechanism for protein expression and a complete absence of protein recycling or turnover. As a result, the crystallins are some of the oldest proteins in the human body. Lack of protein repair or recycling means the lens tends to accumulate damage with age in the form of protein posttranslational modifications. The crystallins can be subject to a wide range of age-related changes, including isomerisation, deamidation and racemisation. Many of these modification are highly correlated with cataract formation and represent a biochemical mechanism for age-related blindness.

show abstract