Polyubiquitin ligand-induced phase transitions are optimized by spacing between ubiquitin units

Galagedera S Dao T, Enos S, Chaudhuri A, Schmit J, CastaƱeda C, Proceedings of the National Academy of Sciences 120(42) (2023) DOI

SASDR67 – HOTag6 tetramerization domain followed by a (Gly-Ser)10 linker fused to human monoubiquitin

HOTag-(GS)10-Ubiquitin
MWI(0) 54 kDa
MWexpected 56 kDa
VPorod 84 nm3
log I(s) 1.50×10-2 1.50×10-3 1.50×10-4 1.50×10-5
HOTag-(GS)10-Ubiquitin small angle scattering data  s, nm-1
ln I(s)
HOTag-(GS)10-Ubiquitin Guinier plot ln 1.50×10-2 Rg: 4.0 nm 0 (4.0 nm)-2 s2
(sRg)2I(s)/I(0)
HOTag-(GS)10-Ubiquitin Kratky plot 1.104 0 3 sRg
p(r)
HOTag-(GS)10-Ubiquitin pair distance distribution function Rg: 4.1 nm 0 Dmax: 14.8 nm

Data validation


There are no models related to this curve.

Synchrotron SAXS data from solutions of HOTag6 tetramerization domain followed by a (Gly-Ser)10 linker fused to human monoubiquitin in 20 mM sodium phosphate, 0.5 mM EDTA, 0.02 % NaN3, pH 6.8 were collected on the BioCAT 18ID beam line at the Advanced Photon Source (APS), Argonne National Laboratory storage ring (Lemont, IL, USA) using a Pilatus3 X 1M detector at a sample-detector distance of 3.7 m and at a wavelength of λ = 0.1033 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 300.00 μl sample at 4.3 mg/ml was injected at a 0.60 ml/min flow rate onto a GE Superdex 200 Increase 10/300 column at 20°C. 46 successive 0.500 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.

HOTag6 is a ~30-amino-acid tetramerization domain followed by a (Gly-Ser)10 linker followed by the sequence for human monoubiquitin (UniProt ID: P0CG47, https://www.uniprot.org/uniprot/P0CG47, amino acids 1-76) . This is a designed protein (no natural variant exists). The HOTag6 sequence is from the Shu group at the University of California, San Francisco (https://doi.org/10.1016/j.molcel.2017.12.008).

HOTag-(GS)10-Ubiquitin
Mol. type   Protein
Organism   synthetic construct
Olig. state   Tetramer
Mon. MW   14.1 kDa
Sequence   FASTA