8D2T

Zebrafish MFSD2A isoform B in inward open ligand-free conformation

ELECTRON MICROSCOPY

Refinement

RMS Deviations
Key	Refinement Restraint Deviation
f_dihedral_angle_d	11.943
f_angle_d	0.703
f_chiral_restr	0.044
f_plane_restr	0.006
f_bond_d	0.004

Sample
Single-particle cryo-EM map of MFSD2A isoform B from zebrafish with a Fab in the inward open ligand-free conformation at an average resolution of 3.4 A, filtered to local resolution

Specimen Preparation
Sample Aggregation State	PARTICLE
Vitrification Instrument	LEICA EM GP
Cryogen Name	ETHANE
Sample Vitrification Details	400-mesh 1.2/1.3 Cu grids (Quantifoil) were made hydrophilic by glow discharging for two times 60 seconds with a current of 15 mA in a PELCO easiGlow ...	400-mesh 1.2/1.3 Cu grids (Quantifoil) were made hydrophilic by glow discharging for two times 60 seconds with a current of 15 mA in a PELCO easiGlow system. The cryo grids were produced using a Leica EM GP (Leica). The chamber was kept at 4 C and 95% humidity (86-91% measured). 3 microliter sample at 3 mg/ml was applied to a glow-discharged holey grid, blotted for 6 s, and plunge frozen into liquid ethane and stored in liquid nitrogen.

3D Reconstruction
Reconstruction Method	SINGLE PARTICLE
Number of Particles	65517
Reported Resolution (Å)	3.4
Resolution Method	FSC 0.143 CUT-OFF
Other Details
Refinement Type
Symmetry Type	POINT

Map-Model Fitting and Refinement
Id	1 (7MJS)	2 (7MJS)
Refinement Space	REAL	REAL
Refinement Protocol	RIGID BODY FIT	FLEXIBLE FIT
Refinement Target
Overall B Value		114
Fitting Procedure
Details

Data Acquisition
Detector Type	GATAN K3 BIOQUANTUM (6k x 4k)
Electron Dose (electrons/Å**2)	50

Imaging Experiment	1
Date of Experiment
Temperature (Kelvin)
Microscope Model	TFS KRIOS
Minimum Defocus (nm)	500
Maximum Defocus (nm)	1800
Minimum Tilt Angle (degrees)
Maximum Tilt Angle (degrees)
Nominal CS	0.01
Imaging Mode	BRIGHT FIELD
Specimen Holder Model	FEI TITAN KRIOS AUTOGRID HOLDER
Nominal Magnification	81000
Calibrated Magnification
Source	FIELD EMISSION GUN
Acceleration Voltage (kV)	300
Imaging Details	Cryo-EM grids were loaded into a 300 keV FEI Titan Krios cryo electron microscope (ThermoFisher Scientific, formerly FEI) at HHMI Janelia Reasearch Campus, Janelia Krios 1, equipped with a Cs corrector, and Gatan energy filter and K3 camera (Gatan Inc.). Movies of 50 frames with 1 e-/A2 per frame (50 e-/A2 total dose) were automatically recorded at a nominal magnification of 81,000x, corresponding to a physical pixel size of 0.844 A/px (superresolution pixel size 0.422 A/px) in CDS mode at a dose rate of 9.5 e-/px/s (~7.5 e-/px/s on the camera through the sample) and a defocus range of -0.5 to -1.8 micrometer using SerialEM. In total, 2,653 and 8,443 movies were collected in two separate imaging sessions, with the first dataset on a 400-mesh copper grid and the second on a 300-mesh UltrAuFoil gold grid.

EM Software
Task	Software Package	Version
PARTICLE SELECTION	RELION	3.1.2
MODEL FITTING	UCSF Chimera
IMAGE ACQUISITION	SerialEM
CTF CORRECTION	Gctf	1.18
INITIAL EULER ASSIGNMENT	RELION	3.1.2
INITIAL EULER ASSIGNMENT	cryoSPARC	v3.3.2
FINAL EULER ASSIGNMENT	cryoSPARC	v3.3.2
CLASSIFICATION	cryoSPARC	v3.3.2
RECONSTRUCTION	cryoSPARC	v3.3.2
MODEL FITTING	Coot
MODEL REFINEMENT	Coot
MODEL REFINEMENT	PHENIX

Image Processing
CTF Correction Type	CTF Correction Details	Number of Particles Selected	Particle Selection Details
PHASE FLIPPING AND AMPLITUDE CORRECTION	Patch CTF	3657332	Good 2D classes generated from ~1,000 manually picked particles served as templates for automatic particle picking in RELION, resulting in 623,644 and 3,033,688 particles in dataset 1 and dataset 2 respectively

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM133198.