A dynamic structural unit of phase-separated heterochromatin protein 1α as revealed by integrative structural analyses

Furukawa A, Yonezawa K, Negami T, Yoshimura Y, Hayashi A, Nakayama J, Adachi N, Senda T, Shimizu K, Terada T, Shimizu N, Nishimura Y, Nucleic Acids Research 53(6) (2025) DOI

SASDU23 – Heterochromatin protein HP1α, S97A mutant, full-length (HP1α_S97A) in 50 mM NaCl

Heterochromatin protein HP1α, S97A mutant, full-length
MWI(0) 43 kDa
MWexpected 41 kDa
VPorod 117 nm3
log I(s) 1.13×10-1 1.13×10-2 1.13×10-3 1.13×10-4
Heterochromatin protein HP1α, S97A mutant, full-length small angle scattering data  s, nm-1
ln I(s)
Heterochromatin protein HP1α, S97A mutant, full-length Guinier plot ln 1.14×10-1 Rg: 4.0 nm 0 (4.0 nm)-2 s2
(sRg)2I(s)/I(0)
Heterochromatin protein HP1α, S97A mutant, full-length Kratky plot 1.104 0 3 sRg
p(r)
Heterochromatin protein HP1α, S97A mutant, full-length pair distance distribution function Rg: 4.1 nm 0 Dmax: 14.4 nm

Data validation


There are no models related to this curve.

Synchrotron SAXS data from solutions of heterochromatin protein HP1α (S97A mutant, full-length) in 50 mM NaCl in 20 mM sodium phosphate, 50 mM NaCl, 1 mM DTT, pH 7 were collected on the BL-10C beam line at the Photon Factory (PF), High Energy Accelerator Research Organization (KEK; Tsukuba, Japan) using a Pilatus3 2M detector at a sample-detector distance of 2.0 m and at a wavelength of λ = 0.1213 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 250.00 μl sample at 11.2 mg/ml was injected onto a Cytiva Superdex 200 Increase 10/300 column at 20°C. The flow rate was set to 0.05 mL/min around the peak region. 311 successive 20 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.

SEC-SAXS experiment was performed using an HPLC system, Prominence-i (SHIMADZU). SEC-MALS experiments were performed before the SEC-SAXS experiments and the molecular weight was estimated to be 45.7 kDa.

Heterochromatin protein HP1α, S97A mutant, full-length (HP1α)
Mol. type   Protein
Organism   Homo sapiens
Olig. state   Dimer
Mon. MW   20.5 kDa
Sequence   FASTA