HEADER MEMBRANE PROTEIN 17-SEP-25 9WTY TITLE STRUCTURE OF HOCTN1 IN APO STATE COMPND MOL_ID: 1; COMPND 2 MOLECULE: SOLUTE CARRIER FAMILY 22 MEMBER 4; COMPND 3 CHAIN: A; COMPND 4 SYNONYM: ERGOTHIONEINE TRANSPORTER,ET TRANSPORTER,ETTH,ORGANIC COMPND 5 CATION/CARNITINE TRANSPORTER 1,OCTN1; COMPND 6 ENGINEERED: YES SOURCE MOL_ID: 1; SOURCE 2 ORGANISM_SCIENTIFIC: HOMO SAPIENS; SOURCE 3 ORGANISM_COMMON: HUMAN; SOURCE 4 ORGANISM_TAXID: 9606; SOURCE 5 GENE: SLC22A4, ETT, OCTN1, UT2H; SOURCE 6 EXPRESSION_SYSTEM: HOMO SAPIENS; SOURCE 7 EXPRESSION_SYSTEM_TAXID: 9606 KEYWDS TRANSPORTER, CANCER, DRUG TARGET, MEMBRANE PROTEIN EXPDTA ELECTRON MICROSCOPY AUTHOR B.XU REVDAT 1 23-SEP-26 9WTY 0 JRNL AUTH B.XU,S.LIANG,Z.WANG,X.ZHOU,L.WANG,Q.LIANG,X.LIU,W.GUO,S.SHI, JRNL AUTH 2 C.ZHU,S.YE,Z.LOU,Y.WANG JRNL TITL STRUCTURAL AND MECHANISTIC INSIGHTS INTO OCTN1-MEDIATED JRNL TITL 2 TRANSPORT AND CANCER CELL PROLIFERATION JRNL REF NAT COMMUN 2026 JRNL REFN ESSN 2041-1723 JRNL DOI 10.1038/S41467-026-77727-2 REMARK 2 REMARK 2 RESOLUTION. 3.11 ANGSTROMS. REMARK 3 REMARK 3 REFINEMENT. REMARK 3 SOFTWARE PACKAGES : CRYOSPARC, PHENIX, COOT REMARK 3 RECONSTRUCTION SCHEMA : NULL REMARK 3 REMARK 3 EM MAP-MODEL FITTING AND REFINEMENT REMARK 3 PDB ENTRY : NULL REMARK 3 REFINEMENT SPACE : NULL REMARK 3 REFINEMENT PROTOCOL : NULL REMARK 3 REFINEMENT TARGET : NULL REMARK 3 OVERALL ANISOTROPIC B VALUE : NULL REMARK 3 REMARK 3 FITTING PROCEDURE : NULL REMARK 3 REMARK 3 EM IMAGE RECONSTRUCTION STATISTICS REMARK 3 NOMINAL PIXEL SIZE (ANGSTROMS) : NULL REMARK 3 ACTUAL PIXEL SIZE (ANGSTROMS) : NULL REMARK 3 EFFECTIVE RESOLUTION (ANGSTROMS) : 3.110 REMARK 3 NUMBER OF PARTICLES : 348573 REMARK 3 CTF CORRECTION METHOD : PHASE FLIPPING AND AMPLITUDE REMARK 3 CORRECTION REMARK 3 REMARK 3 EM RECONSTRUCTION MAGNIFICATION CALIBRATION: NULL REMARK 3 REMARK 3 OTHER DETAILS: NULL REMARK 4 REMARK 4 9WTY COMPLIES WITH FORMAT V. 3.30, 13-JUL-11 REMARK 100 REMARK 100 THIS ENTRY HAS BEEN PROCESSED BY PDBC ON 20-SEP-25. REMARK 100 THE DEPOSITION ID IS D_1300063800. REMARK 245 REMARK 245 EXPERIMENTAL DETAILS REMARK 245 RECONSTRUCTION METHOD : SINGLE PARTICLE REMARK 245 SPECIMEN TYPE : NULL REMARK 245 REMARK 245 ELECTRON MICROSCOPE SAMPLE REMARK 245 SAMPLE TYPE : PARTICLE REMARK 245 PARTICLE TYPE : POINT REMARK 245 NAME OF SAMPLE : HOCTN1 REMARK 245 SAMPLE CONCENTRATION (MG ML-1) : NULL REMARK 245 SAMPLE SUPPORT DETAILS : NULL REMARK 245 SAMPLE VITRIFICATION DETAILS : NULL REMARK 245 SAMPLE BUFFER : NULL REMARK 245 PH : 8.00 REMARK 245 SAMPLE DETAILS : NULL REMARK 245 REMARK 245 DATA ACQUISITION REMARK 245 DATE OF EXPERIMENT : NULL REMARK 245 NUMBER OF MICROGRAPHS-IMAGES : NULL REMARK 245 TEMPERATURE (KELVIN) : NULL REMARK 245 MICROSCOPE MODEL : FEI TALOS ARCTICA REMARK 245 DETECTOR TYPE : GATAN K3 (6K X 4K) REMARK 245 MINIMUM DEFOCUS (NM) : 1000.00 REMARK 245 MAXIMUM DEFOCUS (NM) : 1500.00 REMARK 245 MINIMUM TILT ANGLE (DEGREES) : NULL REMARK 245 MAXIMUM TILT ANGLE (DEGREES) : NULL REMARK 245 NOMINAL CS : NULL REMARK 245 IMAGING MODE : BRIGHT FIELD REMARK 245 ELECTRON DOSE (ELECTRONS NM**-2) : 5400.00 REMARK 245 ILLUMINATION MODE : FLOOD BEAM REMARK 245 NOMINAL MAGNIFICATION : NULL REMARK 245 CALIBRATED MAGNIFICATION : NULL REMARK 245 SOURCE : FIELD EMISSION GUN REMARK 245 ACCELERATION VOLTAGE (KV) : 300 REMARK 245 IMAGING DETAILS : NULL REMARK 247 REMARK 247 ELECTRON MICROSCOPY REMARK 247 THE COORDINATES IN THIS ENTRY WERE GENERATED FROM ELECTRON REMARK 247 MICROSCOPY DATA. PROTEIN DATA BANK CONVENTIONS REQUIRE REMARK 247 THAT CRYST1 AND SCALE RECORDS BE INCLUDED, BUT THE VALUES REMARK 247 ON THESE RECORDS ARE MEANINGLESS EXCEPT FOR THE CALCULATION REMARK 247 OF THE STRUCTURE FACTORS. REMARK 300 REMARK 300 BIOMOLECULE: 1 REMARK 300 SEE REMARK 350 FOR THE AUTHOR PROVIDED AND/OR PROGRAM REMARK 300 GENERATED ASSEMBLY INFORMATION FOR THE STRUCTURE IN REMARK 300 THIS ENTRY. THE REMARK MAY ALSO PROVIDE INFORMATION ON REMARK 300 BURIED SURFACE AREA. REMARK 350 REMARK 350 COORDINATES FOR A COMPLETE MULTIMER REPRESENTING THE KNOWN REMARK 350 BIOLOGICALLY SIGNIFICANT OLIGOMERIZATION STATE OF THE REMARK 350 MOLECULE CAN BE GENERATED BY APPLYING BIOMT TRANSFORMATIONS REMARK 350 GIVEN BELOW. BOTH NON-CRYSTALLOGRAPHIC AND REMARK 350 CRYSTALLOGRAPHIC OPERATIONS ARE GIVEN. REMARK 350 REMARK 350 BIOMOLECULE: 1 REMARK 350 AUTHOR DETERMINED BIOLOGICAL UNIT: MONOMERIC REMARK 350 APPLY THE FOLLOWING TO CHAINS: A REMARK 350 BIOMT1 1 1.000000 0.000000 0.000000 0.00000 REMARK 350 BIOMT2 1 0.000000 1.000000 0.000000 0.00000 REMARK 350 BIOMT3 1 0.000000 0.000000 1.000000 0.00000 REMARK 465 REMARK 465 MISSING RESIDUES REMARK 465 THE FOLLOWING RESIDUES WERE NOT LOCATED IN THE REMARK 465 EXPERIMENT. (M=MODEL NUMBER; RES=RESIDUE NAME; C=CHAIN REMARK 465 IDENTIFIER; SSSEQ=SEQUENCE NUMBER; I=INSERTION CODE.) REMARK 465 REMARK 465 M RES C SSSEQI REMARK 465 VAL A 316 REMARK 465 GLU A 317 REMARK 465 GLU A 318 REMARK 465 LEU A 319 REMARK 465 ASN A 320 REMARK 465 PRO A 321 REMARK 465 LEU A 322 REMARK 465 LYS A 323 REMARK 465 GLN A 324 REMARK 465 GLN A 325 REMARK 465 LYS A 326 REMARK 465 ALA A 327 REMARK 465 PHE A 328 REMARK 465 LYS A 524 REMARK 465 VAL A 525 REMARK 465 LYS A 526 REMARK 465 TRP A 527 REMARK 465 PHE A 528 REMARK 465 ARG A 529 REMARK 465 SER A 530 REMARK 465 GLY A 531 REMARK 465 LYS A 532 REMARK 465 LYS A 533 REMARK 465 THR A 534 REMARK 465 ARG A 535 REMARK 465 ASP A 536 REMARK 465 SER A 537 REMARK 465 MET A 538 REMARK 465 GLU A 539 REMARK 465 THR A 540 REMARK 465 GLU A 541 REMARK 465 GLU A 542 REMARK 465 ASN A 543 REMARK 465 PRO A 544 REMARK 465 LYS A 545 REMARK 465 VAL A 546 REMARK 465 LEU A 547 REMARK 465 ILE A 548 REMARK 465 THR A 549 REMARK 465 ALA A 550 REMARK 465 PHE A 551 REMARK 500 REMARK 500 GEOMETRY AND STEREOCHEMISTRY REMARK 500 SUBTOPIC: CLOSE CONTACTS IN SAME ASYMMETRIC UNIT REMARK 500 REMARK 500 THE FOLLOWING ATOMS ARE IN CLOSE CONTACT. REMARK 500 REMARK 500 ATM1 RES C SSEQI ATM2 RES C SSEQI DISTANCE REMARK 500 OD1 ASP A 362 OH TYR A 490 2.18 REMARK 500 REMARK 500 REMARK: NULL REMARK 500 REMARK 500 GEOMETRY AND STEREOCHEMISTRY REMARK 500 SUBTOPIC: COVALENT BOND ANGLES REMARK 500 REMARK 500 THE STEREOCHEMICAL PARAMETERS OF THE FOLLOWING RESIDUES REMARK 500 HAVE VALUES WHICH DEVIATE FROM EXPECTED VALUES BY MORE REMARK 500 THAN 6*RMSD (M=MODEL NUMBER; RES=RESIDUE NAME; C=CHAIN REMARK 500 IDENTIFIER; SSEQ=SEQUENCE NUMBER; I=INSERTION CODE). REMARK 500 REMARK 500 STANDARD TABLE: REMARK 500 FORMAT: (10X,I3,1X,A3,1X,A1,I4,A1,3(1X,A4,2X),12X,F5.1) REMARK 500 REMARK 500 EXPECTED VALUES PROTEIN: ENGH AND HUBER, 1999 REMARK 500 EXPECTED VALUES NUCLEIC ACID: CLOWNEY ET AL 1996 REMARK 500 REMARK 500 M RES CSSEQI ATM1 ATM2 ATM3 REMARK 500 PRO A 266 CA - N - CD ANGL. DEV. = -17.4 DEGREES REMARK 500 PRO A 266 N - CD - CG ANGL. DEV. = -9.1 DEGREES REMARK 500 PRO A 476 CA - N - CD ANGL. DEV. = -8.8 DEGREES REMARK 500 REMARK 500 REMARK: NULL REMARK 500 REMARK 500 GEOMETRY AND STEREOCHEMISTRY REMARK 500 SUBTOPIC: TORSION ANGLES REMARK 500 REMARK 500 TORSION ANGLES OUTSIDE THE EXPECTED RAMACHANDRAN REGIONS: REMARK 500 (M=MODEL NUMBER; RES=RESIDUE NAME; C=CHAIN IDENTIFIER; REMARK 500 SSEQ=SEQUENCE NUMBER; I=INSERTION CODE). REMARK 500 REMARK 500 STANDARD TABLE: REMARK 500 FORMAT:(10X,I3,1X,A3,1X,A1,I4,A1,4X,F7.2,3X,F7.2) REMARK 500 REMARK 500 EXPECTED VALUES: GJ KLEYWEGT AND TA JONES (1996). PHI/PSI- REMARK 500 CHOLOGY: RAMACHANDRAN REVISITED. STRUCTURE 4, 1395 - 1400 REMARK 500 REMARK 500 M RES CSSEQI PSI PHI REMARK 500 ARG A 72 -120.35 60.48 REMARK 500 SER A 82 135.13 -170.68 REMARK 500 SER A 112 -179.86 -69.57 REMARK 500 LYS A 224 -143.07 62.98 REMARK 500 ALA A 310 -3.94 68.16 REMARK 500 ILE A 312 -60.75 -121.80 REMARK 500 ASP A 331 -3.33 67.64 REMARK 500 THR A 335 163.29 64.35 REMARK 500 ASP A 362 -167.52 -74.77 REMARK 500 ALA A 363 77.14 -112.68 REMARK 500 ARG A 397 -61.82 -95.72 REMARK 500 TYR A 484 -10.53 71.69 REMARK 500 SER A 510 178.93 61.33 REMARK 500 GLU A 517 49.80 -92.45 REMARK 500 REMARK 500 REMARK: NULL REMARK 900 REMARK 900 RELATED ENTRIES REMARK 900 RELATED ID: EMD-66227 RELATED DB: EMDB REMARK 900 STRUCTURE OF HOCTN1 IN APO STATE DBREF 9WTY A 1 551 UNP Q9H015 S22A4_HUMAN 1 551 SEQRES 1 A 551 MET ARG ASP TYR ASP GLU VAL ILE ALA PHE LEU GLY GLU SEQRES 2 A 551 TRP GLY PRO PHE GLN ARG LEU ILE PHE PHE LEU LEU SER SEQRES 3 A 551 ALA SER ILE ILE PRO ASN GLY PHE ASN GLY MET SER VAL SEQRES 4 A 551 VAL PHE LEU ALA GLY THR PRO GLU HIS ARG CYS ARG VAL SEQRES 5 A 551 PRO ASP ALA ALA ASN LEU SER SER ALA TRP ARG ASN ASN SEQRES 6 A 551 SER VAL PRO LEU ARG LEU ARG ASP GLY ARG GLU VAL PRO SEQRES 7 A 551 HIS SER CYS SER ARG TYR ARG LEU ALA THR ILE ALA ASN SEQRES 8 A 551 PHE SER ALA LEU GLY LEU GLU PRO GLY ARG ASP VAL ASP SEQRES 9 A 551 LEU GLY GLN LEU GLU GLN GLU SER CYS LEU ASP GLY TRP SEQRES 10 A 551 GLU PHE SER GLN ASP VAL TYR LEU SER THR VAL VAL THR SEQRES 11 A 551 GLU TRP ASN LEU VAL CYS GLU ASP ASN TRP LYS VAL PRO SEQRES 12 A 551 LEU THR THR SER LEU PHE PHE VAL GLY VAL LEU LEU GLY SEQRES 13 A 551 SER PHE VAL SER GLY GLN LEU SER ASP ARG PHE GLY ARG SEQRES 14 A 551 LYS ASN VAL LEU PHE ALA THR MET ALA VAL GLN THR GLY SEQRES 15 A 551 PHE SER PHE LEU GLN ILE PHE SER ILE SER TRP GLU MET SEQRES 16 A 551 PHE THR VAL LEU PHE VAL ILE VAL GLY MET GLY GLN ILE SEQRES 17 A 551 SER ASN TYR VAL VAL ALA PHE ILE LEU GLY THR GLU ILE SEQRES 18 A 551 LEU GLY LYS SER VAL ARG ILE ILE PHE SER THR LEU GLY SEQRES 19 A 551 VAL CYS THR PHE PHE ALA VAL GLY TYR MET LEU LEU PRO SEQRES 20 A 551 LEU PHE ALA TYR PHE ILE ARG ASP TRP ARG MET LEU LEU SEQRES 21 A 551 LEU ALA LEU THR VAL PRO GLY VAL LEU CYS VAL PRO LEU SEQRES 22 A 551 TRP TRP PHE ILE PRO GLU SER PRO ARG TRP LEU ILE SER SEQRES 23 A 551 GLN ARG ARG PHE ARG GLU ALA GLU ASP ILE ILE GLN LYS SEQRES 24 A 551 ALA ALA LYS MET ASN ASN ILE ALA VAL PRO ALA VAL ILE SEQRES 25 A 551 PHE ASP SER VAL GLU GLU LEU ASN PRO LEU LYS GLN GLN SEQRES 26 A 551 LYS ALA PHE ILE LEU ASP LEU PHE ARG THR ARG ASN ILE SEQRES 27 A 551 ALA ILE MET THR ILE MET SER LEU LEU LEU TRP MET LEU SEQRES 28 A 551 THR SER VAL GLY TYR PHE ALA LEU SER LEU ASP ALA PRO SEQRES 29 A 551 ASN LEU HIS GLY ASP ALA TYR LEU ASN CYS PHE LEU SER SEQRES 30 A 551 ALA LEU ILE GLU ILE PRO ALA TYR ILE THR ALA TRP LEU SEQRES 31 A 551 LEU LEU ARG THR LEU PRO ARG ARG TYR ILE ILE ALA ALA SEQRES 32 A 551 VAL LEU PHE TRP GLY GLY GLY VAL LEU LEU PHE ILE GLN SEQRES 33 A 551 LEU VAL PRO VAL ASP TYR TYR PHE LEU SER ILE GLY LEU SEQRES 34 A 551 VAL MET LEU GLY LYS PHE GLY ILE THR SER ALA PHE SER SEQRES 35 A 551 MET LEU TYR VAL PHE THR ALA GLU LEU TYR PRO THR LEU SEQRES 36 A 551 VAL ARG ASN MET ALA VAL GLY VAL THR SER THR ALA SER SEQRES 37 A 551 ARG VAL GLY SER ILE ILE ALA PRO TYR PHE VAL TYR LEU SEQRES 38 A 551 GLY ALA TYR ASN ARG MET LEU PRO TYR ILE VAL MET GLY SEQRES 39 A 551 SER LEU THR VAL LEU ILE GLY ILE LEU THR LEU PHE PHE SEQRES 40 A 551 PRO GLU SER LEU GLY MET THR LEU PRO GLU THR LEU GLU SEQRES 41 A 551 GLN MET GLN LYS VAL LYS TRP PHE ARG SER GLY LYS LYS SEQRES 42 A 551 THR ARG ASP SER MET GLU THR GLU GLU ASN PRO LYS VAL SEQRES 43 A 551 LEU ILE THR ALA PHE HELIX 1 AA1 ASP A 3 GLY A 12 1 10 HELIX 2 AA2 GLY A 15 ALA A 27 1 13 HELIX 3 AA3 ILE A 29 ASN A 35 1 7 HELIX 4 AA4 MET A 37 ALA A 43 1 7 HELIX 5 AA5 SER A 59 ASN A 65 1 7 HELIX 6 AA6 ARG A 85 SER A 93 1 9 HELIX 7 AA7 VAL A 128 ASN A 133 1 6 HELIX 8 AA8 TRP A 140 GLY A 168 1 29 HELIX 9 AA9 LYS A 170 ILE A 188 1 19 HELIX 10 AB1 SER A 192 LEU A 222 1 31 HELIX 11 AB2 LYS A 224 ILE A 253 1 30 HELIX 12 AB3 ASP A 255 VAL A 265 1 11 HELIX 13 AB4 PRO A 266 PHE A 276 5 11 HELIX 14 AB5 SER A 280 GLN A 287 1 8 HELIX 15 AB6 ARG A 289 ASN A 305 1 17 HELIX 16 AB7 THR A 335 LEU A 361 1 27 HELIX 17 AB8 ASP A 369 THR A 394 1 26 HELIX 18 AB9 ARG A 398 GLN A 416 1 19 HELIX 19 AC1 TYR A 423 ALA A 449 1 27 HELIX 20 AC2 ARG A 457 ALA A 475 1 19 HELIX 21 AC3 PRO A 476 PHE A 478 5 3 HELIX 22 AC4 MET A 487 PHE A 507 1 21 SHEET 1 AA1 2 LEU A 69 ARG A 70 0 SHEET 2 AA1 2 VAL A 77 PRO A 78 -1 O VAL A 77 N ARG A 70 SHEET 1 AA2 2 ARG A 83 TYR A 84 0 SHEET 2 AA2 2 GLN A 110 GLU A 111 -1 O GLU A 111 N ARG A 83 SSBOND 1 CYS A 50 CYS A 113 1555 1555 2.03 SSBOND 2 CYS A 81 CYS A 136 1555 1555 2.03 CRYST1 1.000 1.000 1.000 90.00 90.00 90.00 P 1 ORIGX1 1.000000 0.000000 0.000000 0.00000 ORIGX2 0.000000 1.000000 0.000000 0.00000 ORIGX3 0.000000 0.000000 1.000000 0.00000 SCALE1 1.000000 0.000000 0.000000 0.00000 SCALE2 0.000000 1.000000 0.000000 0.00000 SCALE3 0.000000 0.000000 1.000000 0.00000 CONECT 399 887 CONECT 642 1077 CONECT 887 399 CONECT 1077 642 MASTER 207 0 0 22 4 0 0 6 4045 1 4 43 END