3JAJ | pdb_00003jaj

Structure of the engaged state of the mammalian SRP-ribosome complex

ELECTRON MICROSCOPY

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Starting Model(s)

Initial Refinement Model(s)
Type	Source	Accession Code	Details
experimental model	PDB	1WGW
experimental model	PDB	4P3E
experimental model	PDB	1E80
experimental model	PDB	1E8S
experimental model	PDB	3J7O
experimental model	PDB	3J7P
experimental model	PDB	1QB2

Sample
Engaged ribosome SRP complex
Sample Components
80S ribosome
Signal recognition particle

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	FEI VITROBOT MARK IV
Cryogen Name	ETHANE
Sample Vitrification Details	3 uL of sample was incubated on the grid for 30 seconds, blotted for 3 seconds, then flash-frozen in liquid ethane (FEI VITROBOT MARK IV).

3D Reconstruction
Reconstruction Method	SINGLE PARTICLE
Number of Particles	52061
Reported Resolution (Å)	3.75
Resolution Method	FSC 0.143 CUT-OFF
Other Details	gold-standard
Refinement Type	HALF-MAPS REFINED INDEPENDENTLY
Symmetry Type	POINT
Point Symmetry	C1

Map-Model Fitting and Refinement
Id	1 (1WGW, 4P3E, 1E80, 1E8S, 3J7O, 3J7P)	2 (1QB2)
Refinement Space	RECIPROCAL	REAL
Refinement Protocol		RIGID BODY FIT
Refinement Target	R-factor
Overall B Value
Fitting Procedure
Details		METHOD--rigid body

Data Acquisition
Detector Type	FEI FALCON II (4k x 4k)
Electron Dose (electrons/Å**2)	27

Imaging Experiment	1
Date of Experiment	2014-06-16
Temperature (Kelvin)
Microscope Model	FEI TITAN KRIOS
Minimum Defocus (nm)	1000
Maximum Defocus (nm)	3500
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS	2.7
Imaging Mode	BRIGHT FIELD
Specimen Holder Model
Nominal Magnification	59000
Calibrated Magnification
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	300
Imaging Details

EM Software
Task	Software Package	Version
MODEL FITTING	Coot
MODEL FITTING	REFMAC
MODEL FITTING	UCSF Chimera
RECONSTRUCTION	RELION

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
	Each particle