SAXS reveals the molecular basis underlying pH-driven G3BP1 conformational dynamics: implications for stress granule formation

SASDWH8 – NTF2L domain and acidic IDR1 region of G3BP1 (NTF2LA, residues 1-232) at pH 7.5, 150 mM NaCl

NTF2L domain and IDR1 of stress granule core protein G3BP1
MWexperimental 60 kDa
MWexpected 53 kDa
VPorod 108 nm3
log I(s) 1.11×10-1 1.11×10-2 1.11×10-3 1.11×10-4
NTF2L domain and IDR1 of stress granule core protein G3BP1 small angle scattering data  s, nm-1
ln I(s)
NTF2L domain and IDR1 of stress granule core protein G3BP1 Guinier plot ln 1.12×10-1 Rg: 4.0 nm 0 (4.0 nm)-2 s2
(sRg)2I(s)/I(0)
NTF2L domain and IDR1 of stress granule core protein G3BP1 Kratky plot 1.104 0 √3 sRg
p(r)
NTF2L domain and IDR1 of stress granule core protein G3BP1 pair distance distribution function Rg: 4.3 nm 0 Dmax: 16.2 nm

Data validation

Fits and models

log I(s)
 s, nm-1
NTF2L domain and IDR1 of stress granule core protein G3BP1 DAMMIF model
Synchrotron SAXS data from solutions of NTF2L domain and acidic IDR1 region of G3BP1 (NTF2LA, residues 1-232) at pH 7.5, 150 mM NaCl in 20 mM Tris, 150 mM NaCl,, pH 7.5 were collected on the B21 beam line at the Diamond Light Source storage ring (Didcot, UK) using a Eiger 4M detector at a sample-detector distance of 3.7 m and at a wavelength of λ = 0.09464 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 60.00 μl sample at 10 mg/ml was injected at a 0.08 ml/min flow rate onto a Cytiva Superdex 200 Increase 3.2/300 column at 15°C. 600 successive 3 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.

NTF2L domain and IDR1 of stress granule core protein G3BP1 (NTF2A)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Dimer
Mon. MW   26.7 kDa
 
UniProt   Q13283 (1-232)
Sequence   FASTA