Binding structures of SERF1a with NT17-polyQ peptides of huntingtin exon 1 revealed by SEC-SWAXS, NMR and molecular simulation.

Lin TC, Shih O Tsai TY, Yeh YQ, Liao KF, Mansel BW, Shiu YJ, Chang CF, Su AC, Chen YR, Jeng US, IUCrJ (2024) Europe PMC

SASDVP5 – HTT0 peptide

HTT0
MWexperimental 10 kDa
MWexpected 4 kDa
VPorod 4 nm3
log I(s) 8.96×10-3 8.96×10-4 8.96×10-5 8.96×10-6
HTT0 small angle scattering data  s, nm-1
ln I(s)
HTT0 Guinier plot ln 8.96×10-3 Rg: 1.5 nm 0 (1.5 nm)-2 s2
(sRg)2I(s)/I(0)
HTT0 Kratky plot 1.104 0 3 sRg
Dmax: 6 nm

Data validation


Fits and models


log I(s)
 s, nm-1
HTT0 ROSETTA model

Synchrotron SAXS data from solutions of HTT0 peptide in sodium phosphate buffer, pH 7.4 were collected on the TPS13A beam line at the NSRRC (Hsinchu, Taiwan) using a Eiger X 1M & 9M detector at a sample-detector distance of 2.5 m and at a wavelength of λ = 0.08265 nm (I(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). In-line size-exclusion chromatography (SEC) SAS was employed. The SEC parameters were as follows: A 70.00 μl sample at 10 mg/ml was injected at a 0.35 ml/min flow rate onto a Agilent Bio SEC-3, 300 Å column at 10°C. 10 successive 2 second frames were collected. The data were normalized to the intensity of the transmitted beam and radially averaged; the scattering of the solvent-blank was subtracted.

The sodium phosphate buffer solution contains 480 μL of 10 mM PB, pH 7.4, 16.5 μL of 100 mM NaOH, and 10 μL of 1% trifluoroacetic acid (TFA).

HTT0
Mol. type   Protein
Organism   synthetic construct
Olig. state   Monomer
Mon. MW   4.0 kDa
Sequence   FASTA