Structural analysis of the SRP Alu domain from Plasmodium falciparum reveals a non-canonical open conformation.

Soni K, Kempf G, Manalastas-Cantos K, Hendricks A, Flemming D, Guizetti J, Simon B, Frischknecht F, Svergun DI, Wild K, Sinning I, Commun Biol 4(1):600 (2021) Europe PMC

SASDK64 – Signal recognition particle SRP9/14 heterodimer in complex with the 5' domain of SRP Alu RNA from Plasmodium falciparum

Signal recognition particle 9
Signal recognition particle 14
SRP Alu RNA 5' domain
MWexperimental 53 kDa
MWexpected 49 kDa
VPorod 77 nm3
log I(s) 2.91×101 2.91×100 2.91×10-1 2.91×10-2
Signal recognition particle 9 Signal recognition particle 14 SRP Alu RNA 5' domain small angle scattering data  s, nm-1
ln I(s)
Signal recognition particle 9 Signal recognition particle 14 SRP Alu RNA 5' domain Guinier plot ln 2.92×101 Rg: 3.2 nm 0 (3.2 nm)-2 s2
(sRg)2I(s)/I(0)
Signal recognition particle 9 Signal recognition particle 14 SRP Alu RNA 5' domain Kratky plot 1.104 0 3 sRg
p(r)
Signal recognition particle 9 Signal recognition particle 14 SRP Alu RNA 5' domain pair distance distribution function Rg: 3.3 nm 0 Dmax: 11.9 nm

Data validation


Fits and models


log I(s)
 s, nm-1
Signal recognition particle 9 Signal recognition particle 14 SRP Alu RNA 5' domain MONSA model

log I(s)
 s, nm-1
Signal recognition particle 9 Signal recognition particle 14 SRP Alu RNA 5' domain MONSA model

log I(s)
 s, nm-1
Signal recognition particle 9 Signal recognition particle 14 SRP Alu RNA 5' domain MONSA model

Synchrotron SAXS data from solutions of the SRP9/14 heterodimer bound to the 5' domain of SRP Alu RNA in 20 mM HEPES pH 7.5, 150 mM NaCl, 10 mM MgCl2, 10 mM KCl, 1mM DTT, pH 7.5 were collected on the BM29 beam line at the ESRF (Grenoble, France) using a Pilatus 1M detector at a wavelength of λ = 0.099 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 200.00 μl sample at 2.4 mg/ml was injected at a 0.60 ml/min flow rate onto a GE Superdex 200 10/300 column at 20°C. 2500 successive 1 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.

MONSA phase models are presented representing the fits to the data of the protein (top) and RNA (middle) components, and the final complex (bottom).

Signal recognition particle 9 (SRP9)
Mol. type   Protein
Organism   Plasmodium falciparum
Olig. state   Monomer
Mon. MW   12.1 kDa
 
UniProt   F2X1X5 (1-103)
Sequence   FASTA
 
Signal recognition particle 14 (SRP14)
Mol. type   Protein
Organism   Plasmodium falciparum
Olig. state   Monomer
Mon. MW   12.0 kDa
 
UniProt   F2X1X6 (1-104)
Sequence   FASTA
 
SRP Alu RNA 5' domain
Mol. type   RNA
Organism   Plasmodium falciparum
Olig. state   Monomer
Mon. MW   24.4 kDa
Sequence   FASTA