Structural basis of the zinc-induced cytoplasmic aggregation of the RNA-binding protein SFPQ

Huang J, Ringuet M, Whitten A, Caria S, Lim Y, Badhan R, Anggono V, Lee M, Nucleic Acids Research 48(6):3356-3365 (2020) DOI

SASDMH8 – Splicing factor, proline- and glutamine-rich-QM-TM bound to Non-POU domain-containing octamer-binding protein: SFPQ(276-598)-QM-TM / NONO(52-312) heterodimer

Splicing factor, proline- and glutamine-rich
Non-POU domain-containing octamer-binding protein
MWI(0) 55 kDa
MWexpected 68 kDa
VPorod 80 nm3
log I(s) 3.03×10-2 3.03×10-3 3.03×10-4 3.03×10-5
Splicing factor, proline- and glutamine-rich Non-POU domain-containing octamer-binding protein small angle scattering data  s, nm-1
ln I(s)
Splicing factor, proline- and glutamine-rich Non-POU domain-containing octamer-binding protein Guinier plot ln 3.04×10-2 Rg: 3.6 nm 0 (3.6 nm)-2 s2
(sRg)2I(s)/I(0)
Splicing factor, proline- and glutamine-rich Non-POU domain-containing octamer-binding protein Kratky plot 1.104 0 √3 sRg
p(r)
Splicing factor, proline- and glutamine-rich Non-POU domain-containing octamer-binding protein pair distance distribution function Rg: 3.9 nm 0 Dmax: 16.5 nm

Data validation

Fits and models

log I(s)
 s, nm-1
Splicing factor, proline- and glutamine-rich Non-POU domain-containing octamer-binding protein PDB (PROTEIN DATA BANK) model
X-ray synchrotron radiation scattering data from solutions of human SFPQ(276-598)-QM-TM/NONO(53-512) in 20 mM Tris 250 mM NaCl, pH 7.5 were collected on the SAXS/WAXS beam line of the Australian Synchrotron (Melbourne, Australia) using a 2D Photon counting Dectris/Pilatus 1M pixel detector (s = 4πsinθ/λ, where 2θ is the scattering angle). Here QM refers to the quadruple mutatation (L535A, L529A, L546A, M549A), and TM refers to the additional triple mutation (H483A, H528A, H530A) in the SFPQ(276-598) protein. Approximately 100 uL of sample at 0.75 mg/mL was drawn into a 1 mm capillary and as the sample passed through the beam, forty successive 1 second frames were collected. The data were normalized to the intensity of the transmitted beam, placed on an absolute scale relative to a water standard, and radially averaged. The scattering of the solvent-blank was subtracted to yield the scattering profile of the protein complex. The data was modelled using CRYSOL and PDB structure 4WIJ:B. Included in the attached zip archive are concentration series (0.38 - 3.0 mg/mL) for the protein in the absence and presence of Zn(II) (protein to zinc molar ratio of 1 : 0.5).

Splicing factor, proline- and glutamine-rich (SFPQ-QM-TM)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Monomer
Mon. MW   37.8 kDa
 
UniProt   P23246 (276-598)
Sequence   FASTA
 
Non-POU domain-containing octamer-binding protein (NONO)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Monomer
Mon. MW   30.1 kDa
 
UniProt   Q15233 (53-312)
Sequence   FASTA
 
PDB ID   4WIJ