Fig. 4.

Diflunisal increases thermal stability of the mutant TTR. (A) SDS/PAGE of proteins (0.2 mg/mL) before (0) or after 24 h of incubation at 80 °C (10) either without (−) or with (+) diflunisal at 360 μM, 25:1 (mol/mol) drug to TTR monomers. The proteins were cross-linked by glutaraldehyde, and the gels were developed with Gel Code Blue stain reagent. TTR monomer (TTR₁), dimer (TTR₂), and tetramer (TTR₄) are indicated. (B) Kinetics of protein unfolding during incubation at 80 °C in the absence or in the presence of diflunisal at 5:1 (mol/mol) drug to TTR monomers monitored by CD at 291 nm for Trp solvent exposure. The data for two ATTR mutants, Glu51_Ser52dup and Leu55Pro, are shown; WT remains fully folded under these conditions. deg, degrees; difl, diflunisal; ME, molar ellipticity.