Cryo-EM structure of the closed NF449-bound human P2X1 receptor
4,4',4'',4'''-{carbonylbis[azanediylbenzene-5,1,3-triylbis(carbonylazanediyl)]}tetra(benzene-1,3-disulfonic acid)
N-acetyl-beta-D-glucosamine; 2-acetamido-2-deoxy-beta-D-glucose; 2-acetamido-2-deoxy-D-glucose; 2-acetamido-2-deoxy-glucose; N-ACETYL-D-GLUCOSAMINE
Structural insights into the human P2X1 receptor and ligand interactions.
Initial fitting was performed in Chimerax and then refinements were performed in Coot and Phenix.
The buffer consists of 50 mM Tris (pH 8), 100 mM NaCl, 0.01% LMNG, and 0.0006% CHS supplemented with 0.1 mM NF449. Additionally, 0.3 mM fluorinated Fos-Choline-8 (fluor-FC8) was added just one minute prior to vitrification.
CTF correction was initially conducted on the set of motion-corrected images, with subsequent local CTF corrections applied to the final subset of particles.
Initial grid screening was conducted using a 200kV TFS Artica cryo-electron microscope prior to imaging on a Titan Krios cryo-electron microscope.
Model used: Glow Discharge Peelco Easyglow
Grids were frozen in liquid ethane using a Vitrobot Mark III operated at 4 degrees Celsius and 100% humidity with 12 blot force and 2 seconds blot time.
Partial sections of the N and C-termini remain unmodelled due to insufficient cryo-EM density.
MARRFQEELAAFLFEYDTPRMVLVRNKKVGVIFRLIQLVVLVYVIGWVFLYEKGYQTSSGLISSVSVKLKGLAVTQLPGL GPQVWDVADYVFPAQGDNSFVVMTNFIVTPKQTQGYCAEHPEGGICKEDSGCTPGKAKRKAQGIRTGKCVAFNDTVKTCE IFGWCPVEVDDDIPRPALLREAENFTLFIKNSISFPRFKVNRRNLVEEVNAAHMKTCLFHKTLHPLCPVFQLGYVVQESG QNFSTLAEKGGVVGITIDWHCDLDWHVRHCRPIYEFHGLYEEKNLSPGFNFRFARHFVENGTNYRHLFKVFGIRFDILVD GKAGKFDIIPTMTTIGSGIGIFGVATVLCDLLLLHILPKRHYYKQKKFKYAEDMGPGAAERDLAATSSTLGLQENMRTS
National Health and Medical Research Council (NHMRC, Australia)
Contains the same protein complexed with ATP instead of NF449 and in a desensitized state rather than closed.
Ion channel, trimer, NF449-bound, closed., MEMBRANE PROTEIN