Did evolution create a flexible ligand-binding cavity in the urokinase receptor through deletion of a plesiotypic disulfide bond?

Leth JM, Mertens HDT, Leth-Espensen KZ, Jørgensen TJD, Ploug M, J Biol Chem (2019) Europe PMC

SASDFA2 – Urokinase plasminogen activator surface receptor, uPAR T51C-V70C, complex with urokinase-type plasminogen activator (Amino Terminal Fragment, ATF).

Urokinase plasminogen activator surface receptor
Urokinase-type plasminogen activator (Amino Terminal Fragment)
MWI(0) 55 kDa
MWexpected 53 kDa
VPorod 77 nm3
log I(s) 4.20×10-2 4.20×10-3 4.20×10-4 4.20×10-5
Urokinase plasminogen activator surface receptor Urokinase-type plasminogen activator (Amino Terminal Fragment) small angle scattering data  s, nm-1
ln I(s)
Urokinase plasminogen activator surface receptor Urokinase-type plasminogen activator (Amino Terminal Fragment) Guinier plot ln 4.20×10-2 Rg: 2.6 nm 0 (2.6 nm)-2 s2
(sRg)2I(s)/I(0)
Urokinase plasminogen activator surface receptor Urokinase-type plasminogen activator (Amino Terminal Fragment) Kratky plot 1.104 0 3 sRg
p(r)
Urokinase plasminogen activator surface receptor Urokinase-type plasminogen activator (Amino Terminal Fragment) pair distance distribution function Rg: 2.6 nm 0 Dmax: 8.5 nm

Data validation


Fits and models


log I(s)
 s, nm-1
Urokinase plasminogen activator surface receptor Urokinase-type plasminogen activator (Amino Terminal Fragment) DAMMIN model

Synchrotron SAXS data from solutions of uPAR T51C-V70C in complex with uPA-ATF in 20 mM PBS, 5 %(v/v) glycerol, pH 7.4 were collected on the EMBL P12 beam line at PETRA III (Hamburg, Germany) using a Pilatus 2M detector at a sample-detector distance of 3.1 m and at a wavelength of λ = 0.124 nm (l(s) vs s, where s = 4πsinθ/λ, and 2θ is the scattering angle). Solute concentrations ranging between 0.3 and 2.5 mg/ml were measured at 10°C. 20 successive 0.050 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 low angle data collected at lower concentrations were extrapolated to infinite dilution and merged with the higher concentration data to yield the final composite scattering curve.

Introduced disulfide in the first LU domain, DI, of uPAR (T51C-V70C).

Urokinase plasminogen activator surface receptor (uPAR)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Monomer
Mon. MW   37.0 kDa
 
UniProt   Q03405
Sequence   FASTA
 
Urokinase-type plasminogen activator (Amino Terminal Fragment) (ATF)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Monomer
Mon. MW   16.1 kDa
 
UniProt   P00749 (1-143)
Sequence   FASTA