An atypical BRCT-BRCT interaction with the XRCC1 scaffold protein compacts human DNA Ligase IIIα within a flexible DNA repair complex.

Hammel M, Rashid I, Sverzhinsky A, Pourfarjam Y, Tsai MS, Ellenberger T, Pascal JM, Kim IK, Tainer JA, Tomkinson AE, Nucleic Acids Res (2020) Europe PMC

SASDJ62 – DNA repair protein XRCC1 monomer /dimer

DNA repair protein XRCC1

MW^experimental	110	kDa
MW^expected	69	kDa
V^Porod	330	nm³

log I(s) 1.47×10² 1.47×10¹ 1.47×10⁰ 1.47×10^-1

DNA repair protein XRCC1 small angle scattering data

s, nm^-1

Log plot Log-Log plot

ln I(s)

ln 1.47×10² R_g: 6.3 nm 0 (6.3 nm)^-2 s²

(sR_g)²I(s)/I(0)

1.104 0 √3 sR_g

p(r)	R_g: 7.4 nm 0 D_max: 26.9 nm

Data validation

Fits and models

log I(s)	s, nm^-1
+3 Δ/σ -3	s, nm^-1

Synchrotron SAXS data from solutions of DNA repair protein XRCC1 in 200 mM NaCl, 20 mM Tris-HCl, pH 7.5 , 2% glycerol, were collected on the 12.3.1 (SIBYLS) beam line at the Advanced Light Source (ALS; Berkeley, CA, USA) using a Pilatus3 X 2M detector at a sample-detector distance of 2.1 m and at a wavelength of λ = 0.1127 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 50.00 μl sample at 5.9 mg/ml was injected at a 0.50 ml/min flow rate onto a Shodex KW403 column at 20°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.

DNA repair protein XRCC1 (XRCC1)
Mol. type		Protein
Organism		Homo sapiens
Olig. state		Unknown
Mon. MW		69.5 kDa

UniProt		P18887 (1-633)
Sequence		FASTA