9KDN: 1 ACTD

The structure of 1 ACTD bound to RNA polymerase II elongation complex with 2 CTG repeats. Determined by electron microscopy at 2.96 Å resolution. Released 12 Nov 2025.

Method
Electron microscopy
Resolution
2.96 Å
Organisms
Saccharomyces cerevisiae S288C, Streptomyces sp., synthetic construct
Chains
16
Atoms
33,014
Mol. weight
548.01 kDa
Ligands
MG, ZN
Released
12 Nov 2025

Explore 9KDN in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9KDN contains 194 α-helices and 231 β-strands across 13 chains. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 77 helices, 69 β-strands

ElementResiduesLengthSheet
β-strand1111
β-strand16-1832
α-helix24-307
β-strand3413
β-strand3714
β-strand4115
β-strand4815
α-helix491
β-strand5214
α-helix56-583
β-strand82-91103
α-helix96-10510
β-strand10616
β-strand11316
α-helix120-1267
α-helix131-14212
β-strand151-15337
β-strand161-16337
α-helix169-1724
β-strand173-17758
β-strand180-18568
α-helix186-1872
β-strand198-20258
α-helix204-2129
α-helix216-2205
α-helix231-2344
β-strand235-24173
α-helix242-2432
α-helix261-28222
α-helix286-30419
α-helix312-3132
β-strand31519
β-strand32119
α-helix3221
α-helix325-3295
α-helix3351
α-helix336-3405
β-strand343-345310
β-strand348-355811
β-strand363-367511
α-helix368-3736
β-strand375-379512
α-helix3801
α-helix385-39410
β-strand402-406512
β-strand412-414312
β-strand431-435512
β-strand441-445511
α-helix452-4543
β-strand455-463911
β-strand468-470311
α-helix475-4784
β-strand486-490511
α-helix495-50410
β-strand506111
α-helix508-5103
β-strand512-513213
β-strand518-519213
α-helix526-5349
β-strand540-541214
α-helix543-5519
α-helix560-5634
β-strand565-567315
β-strand571115
β-strand572-573214
α-helix574-5818
α-helix5831
β-strand588-590316
β-strand605-608416
β-strand611-614416
α-helix619-6224
α-helix629-6368
α-helix639-66022
β-strand663117
α-helix666-6694
α-helix673-69826
α-helix703-7053
α-helix710-73627
α-helix742-7498
α-helix755-7584
α-helix759-7635
β-strand766-767218
β-strand769-770219
β-strand773-774219
α-helix775-7762
α-helix794-7963
β-strand799-800218
α-helix810-84536
β-strand849-850220
β-strand856-857220
β-strand863-865320
α-helix868-8703
β-strand873121
α-helix875-8773
β-strand879-882422
α-helix890-8978
α-helix910-9123
β-strand913123
α-helix924-94623
β-strand953-956422
α-helix960-97112
α-helix9781
β-strand979123
α-helix983-99513
α-helix1005-102521
α-helix1028-10292
α-helix1030-10356
α-helix1039-105618
β-strand1057121
α-helix1058-10592
α-helix1064-107815
α-helix1097-110610
β-strand1115-1119524
β-strand1120125
α-helix1122-11243
α-helix1128-113811
β-strand1141126
α-helix1143-11453
β-strand1147-1154827
α-helix1167-117610
α-helix1185-11873
β-strand1188128
β-strand1191-1197727
α-helix1199-12046
α-helix1209-122012
β-strand1224-1228527
β-strand1237-1242627
β-strand1243128
α-helix1244-12452
α-helix1252-126918
β-strand1274126
β-strand1281-12921224
β-strand1298-13091224
α-helix1313-13175
β-strand1322125
β-strand1328-1329224
α-helix1332-13387
α-helix1341-135717
α-helix1365-137511
α-helix1396-14005
α-helix1405-141511
β-strand1418-141922
α-helix1424-14307
α-helix1437-14393
β-strand1441-1445529
α-helix1447-14537
Chain B: 54 helices, 84 β-strands
ElementResiduesLengthSheet
α-helix231
β-strand24130
α-helix25-262
α-helix29-4012
α-helix45-539
α-helix54-585
α-helix59-646
β-strand68-73631
α-helix80-823
β-strand84-971431
β-strand101-102232
β-strand110-111232
α-helix114-1207
β-strand125-1401631
α-helix146-1472
β-strand150-151231
β-strand156131
β-strand164-171831
α-helix186-1916
β-strand203-205333
β-strand208-212533
β-strand214-218534
α-helix2191
β-strand223-227535
β-strand234-242935
β-strand252-259835
β-strand269-272435
β-strand276136
β-strand280-281235
α-helix282-2898
α-helix294-3018
α-helix308-32114
α-helix327-33711
β-strand338136
α-helix348-3547
α-helix355-3595
α-helix371-38919
α-helix394-3974
α-helix401-4033
β-strand404-407434
α-helix409-43729
α-helix440-4423
α-helix444-4474
α-helix450-46213
β-strand480-482333
α-helix488-4958
β-strand497-499334
α-helix516-5183
β-strand522137
β-strand533134
β-strand536-538334
β-strand539137
β-strand544-545238
α-helix552-5609
α-helix5631
β-strand564-565239
β-strand578-582539
β-strand585-590639
α-helix593-60412
β-strand614-618539
β-strand623-627539
β-strand633-639738
β-strand640-641240
β-strand650-651240
β-strand654130
α-helix655-66814
α-helix681-6866
β-strand690-694538
α-helix695-6995
β-strand703-704238
α-helix707-7104
α-helix728-7292
β-strand740-742338
α-helix745-7484
α-helix753-7553
α-helix759-7613
β-strand762141
α-helix764-77310
β-strand777142
α-helix785-7873
β-strand792-796543
β-strand800144
β-strand804-805245
α-helix807-8093
β-strand821-827746
β-strand828117
β-strand839-842446
α-helix843-8475
β-strand853-8621043
β-strand865147
β-strand871147
β-strand873-874248
β-strand883148
β-strand898149
α-helix899-9002
β-strand904-905243
β-strand910-912349
β-strand914-917448
β-strand924150
β-strand928150
β-strand934-936348
β-strand939-940249
α-helix941-9422
β-strand947-9561043
β-strand962-9721143
β-strand979-982446
β-strand988-994746
β-strand1001-1002251
β-strand1010-1012346
α-helix1016-10205
β-strand1022141
α-helix1023-103816
β-strand1042-1043245
α-helix1052-106110
β-strand1069-1070246
β-strand1072-1073251
α-helix10791
β-strand1080151
α-helix10811
β-strand1085-10941046
β-strand1095142
α-helix1099-11013
β-strand1104-1106311
β-strand1111152
β-strand1118152
α-helix1122-11243
β-strand1128-1130310
α-helix1132-114110
α-helix1144-11485
α-helix1149-11535
β-strand1158-116361
β-strand1172-1174353
β-strand1179-1181353
β-strand1182154
β-strand1187154
β-strand1191-119661
α-helix1198-120912
β-strand1215-121732
Chain C: 13 helices, 12 β-strands
ElementResiduesLengthSheet
β-strand7-13755
β-strand17-23755
α-helix27-3913
β-strand43-541256
α-helix60-689
β-strand72-74357
α-helix77-793
α-helix83-853
β-strand96-104956
α-helix1101
β-strand111-113358
β-strand118-120356
β-strand129-132457
α-helix1331
β-strand145-147358
β-strand152-1621156
α-helix168-1703
β-strand176-179455
α-helix197-2004
α-helix202-2043
α-helix205-2095
α-helix211-2133
α-helix218-2192
β-strand228-233655
α-helix240-26627
Chain D: 9 helices, 3 β-strands
ElementResiduesLengthSheet
α-helix20-223
β-strand36-38359
β-strand44-46359
β-strand49-50229
α-helix52-7120
α-helix119-13315
α-helix139-15012
α-helix157-17014
α-helix174-1829
α-helix188-1947
α-helix196-1983
α-helix204-21714
Chain E: 13 helices, 14 β-strands
ElementResiduesLengthSheet
α-helix3-2523
β-strand28160
α-helix32-354
α-helix39-468
β-strand47161
β-strand53161
β-strand60-62362
β-strand64160
α-helix66-716
β-strand78-82562
β-strand87-88263
α-helix90-10213
β-strand107-112662
β-strand115-116263
α-helix118-1214
β-strand131-136662
α-helix138-1403
α-helix144-1463
β-strand152-155464
α-helix156-1572
α-helix158-16710
α-helix1761
β-strand177-178264
α-helix183-1886
α-helix190-1912
β-strand195-200664
β-strand208-214764
Chain F: 7 helices, 5 β-strands
ElementResiduesLengthSheet
β-strand73129
α-helix76-783
β-strand84165
α-helix85-862
α-helix87-10216
α-helix105-1073
α-helix117-12610
β-strand132-137629
α-helix1381
β-strand143-147529
α-helix148-1503
β-strand152165
Chain G: 4 helices, 15 β-strands
ElementResiduesLengthSheet
β-strand2-131229
α-helix15-173
α-helix22-309
β-strand37-39329
β-strand43-49729
β-strand55129
β-strand60-61229
α-helix621
β-strand68-791229
β-strand85-941066
β-strand98-103666
β-strand106-111666
α-helix112-1143
β-strand120-122367
β-strand129-131367
β-strand136-137267
β-strand142-1521166
β-strand157-162666
β-strand169-170266
Chain H: 4 helices, 8 β-strands
ElementResiduesLengthSheet
β-strand4-161315
β-strand24-30715
β-strand37-42615
β-strand54-60715
α-helix67-682
α-helix81-833
α-helix89-924
β-strand95-1061215
β-strand111-118815
β-strand121-128815
α-helix129-1324
β-strand139-145715

5 more chain groups are not listed. Open the entry in the viewer and use the sequence panel to see them.

Molecules and chains

MoleculeChainsTypeLengthOrganismUniProt
DNA-directed RNA polymerase II subunit RPB1Aprotein1733Saccharomyces cerevisiae S288CP04050 (AlphaFold model)
DNA-directed RNA polymerase II subunit RPB2Bprotein1224Saccharomyces cerevisiae S288CP08518 (AlphaFold model)
DNA-directed RNA polymerase II subunit RPB3Cprotein318Saccharomyces cerevisiae S288CP16370 (AlphaFold model)
DNA-directed RNA polymerase II subunit RPB4Dprotein221Saccharomyces cerevisiae S288CP20433 (AlphaFold model)
DNA-directed RNA polymerases I, II, and III subunit RPABC1Eprotein215Saccharomyces cerevisiae S288CP20434
DNA-directed RNA polymerases I, II, and III subunit RPABC2Fprotein155Saccharomyces cerevisiae S288CP20435
DNA-directed RNA polymerase II subunit RPB7Gprotein171Saccharomyces cerevisiae S288CP34087
DNA-directed RNA polymerases I, II, and III subunit RPABC3Hprotein146Saccharomyces cerevisiae S288CP20436
DNA-directed RNA polymerase II subunit RPB9Iprotein122Saccharomyces cerevisiae S288CP27999
DNA-directed RNA polymerases I, II, and III subunit RPABC5Jprotein70Saccharomyces cerevisiae S288CP22139
DNA-directed RNA polymerase II subunit RPB11Kprotein120Saccharomyces cerevisiae S288CP38902
DNA-directed RNA polymerases I, II, and III subunit RPABC4Lprotein70Saccharomyces cerevisiae S288CP40422

4 more molecules are not listed.

Sequence of entity 1 (A), FASTA
>9KDN_1 DNA-directed RNA polymerase II subunit RPB1 (chains A)
MVGQQYSSAPLRTVKEVQFGLFSPEEVRAISVAKIRFPETMDETQTRAKIGGLNDPRLGS
IDRNLKCQTCQEGMNECPGHFGHIDLAKPVFHVGFIAKIKKVCECVCMHCGKLLLDEHNE
LMRQALAIKDSKKRFAAIWTLCKTKMVCETDVPSEDDPTQLVSRGGCGNTQPTIRKDGLK
LVGSWKKDRATGDADEPELRVLSTEEILNIFKHISVKDFTSLGFNEVFSRPEWMILTCLP
VPPPPVRPSISFNESQRGEDDLTFKLADILKANISLETLEHNGAPHHAIEEAESLLQFHV
ATYMDNDIAGQPQALQKSGRPVKSIRARLKGKEGRIRGNLMGKRVDFSARTVISGDPNLE
LDQVGVPKSIAKTLTYPEVVTPYNIDRLTQLVRNGPNEHPGAKYVIRDSGDRIDLRYSKR
AGDIQLQYGWKVERHIMDNDPVLFNRQPSLHKMSMMAHRVKVIPYSTFRLNLSVTSPYNA
DFDGDEMNLHVPQSEETRAELSQLCAVPLQIVSPQSNKPCMGIVQDTLCGIRKLTLRDTF
IELDQVLNMLYWVPDWDGVIPTPAIIKPKPLWSGKQILSVAIPNGIHLQRFDEGTTLLSP
KDNGMLIIDGQIIFGVVEKKTVGSSNGGLIHVVTREKGPQVCAKLFGNIQKVVNFWLLHN
GFSTGIGDTIADGPTMREITETIAEAKKKVLDVTKEAQANLLTAKHGMTLRESFEDNVVR
FLNEARDKAGRLAEVNLKDLNNVKQMVMAGSKGSFINIAQMSACVGQQSVEGKRIAFGFV
DRTLPHFSKDDYSPESKGFVENSYLRGLTPQEFFFHAMGGREGLIDTAVKTAETGYIQRR
LVKALEDIMVHYDNTTRNSLGNVIQFIYGEDGMDAAHIEKQSLDTIGGSDAAFEKRYRVD
LLNTDHTLDPSLLESGSEILGDLKLQVLLDEEYKQLVKDRKFLREVFVDGEANWPLPVNI
RRIIQNAQQTFHIDHTKPSDLTIKDIVLGVKDLQENLLVLRGKNEIIQNAQRDAVTLFCC
LLRSRLATRRVLQEYRLTKQAFDWVLSNIEAQFLRSVVHPGEMVGVLAAQSIGEPATQMT
LNTFHFAGVASKKVTSGVPRLKEILNVAKNMKTPSLTVYLEPGHAADQEQAKLIRSAIEH
TTLKSVTIASEIYYDPDPRSTVIPEDEEIIQLHFSLLDEEAEQSFDQQSPWLLRLELDRA
AMNDKDLTMGQVGERIKQTFKNDLFVIWSEDNDEKLIIRCRVVRPKSLDAETEAEEDHML
KKIENTMLENITLRGVENIERVVMMKYDRKVPSPTGEYVKEPEWVLETDGVNLSEVMTVP
GIDPTRIYTNSFIDIMEVLGIEAGRAALYKEVYNVIASDGSYVNYRHMALLVDVMTTQGG
LTSVTRHGFNRSNTGALMRCSFEETVEILFEAGASAELDDCRGVSENVILGQMAPIGTGA
FDVMIDEESLVKYMPEQKITEIEDGQDGGVTPYSNESGLVNADLDVKDELMFSPLVDSGS
NDAMAGGFTAYGGADYGEATSPFGAYGEAPTSPGFGVSSPGFSPTSPTYSPTSPAYSPTS
PSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYS
PTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPAYSPTSPSYSPTSPSYSPTSP
SYSPTSPSYSPTSPNYSPTSPSYSPTSPGYSPGSPAYSPKQDEQKHNENENSR
Sequence of entity 2 (B), FASTA
>9KDN_2 DNA-directed RNA polymerase II subunit RPB2 (chains B)
MSDLANSEKYYDEDPYGFEDESAPITAEDSWAVISAFFREKGLVSQQLDSFNQFVDYTLQ
DIICEDSTLILEQLAQHTTESDNISRKYEISFGKIYVTKPMVNESDGVTHALYPQEARLR
NLTYSSGLFVDVKKRTYEAIDVPGRELKYELIAEESEDDSESGKVFIGRLPIMLRSKNCY
LSEATESDLYKLKECPFDMGGYFIINGSEKVLIAQERSAGNIVQVFKKAAPSPISHVAEI
RSALEKGSRFISTLQVKLYGREGSSARTIKATLPYIKQDIPIVIIFRALGIIPDGEILEH
ICYDVNDWQMLEMLKPCVEDGFVIQDRETALDFIGRRGTALGIKKEKRIQYAKDILQKEF
LPHITQLEGFESRKAFFLGYMINRLLLCALDRKDQDDRDHFGKKRLDLAGPLLAQLFKTL
FKKLTKDIFRYMQRTVEEAHDFNMKLAINAKTITSGLKYALATGNWGEQKKAMSSRAGVS
QVLNRYTYSSTLSHLRRTNTPIGRDGKLAKPRQLHNTHWGLVCPAETPEGQACGLVKNLS
LMSCISVGTDPMPIITFLSEWGMEPLEDYVPHQSPDATRVFVNGVWHGVHRNPARLMETL
RTLRRKGDINPEVSMIRDIREKELKIFTDAGRVYRPLFIVEDDESLGHKELKVRKGHIAK
LMATEYQDIEGGFEDVEEYTWSSLLNEGLVEYIDAEEEESILIAMQPEDLEPAEANEEND
LDVDPAKRIRVSHHATTFTHCEIHPSMILGVAASIIPFPDHNQSPRNTYQSAMGKQAMGV
FLTNYNVRMDTMANILYYPQKPLGTTRAMEYLKFRELPAGQNAIVAIACYSGYNQEDSMI
MNQSSIDRGLFRSLFFRSYMDQEKKYGMSITETFEKPQRTNTLRMKHGTYDKLDDDGLIA
PGVRVSGEDVIIGKTTPISPDEEELGQRTAYHSKRDASTPLRSTENGIVDQVLVTTNQDG
LKFVKVRVRTTKIPQIGDKFASRHGQKGTIGITYRREDMPFTAEGIVPDLIINPHAIPSR
MTVAHLIECLLSKVAALSGNEGDASPFTDITVEGISKLLREHGYQSRGFEVMYNGHTGKK
LMAQIFFGPTYYQRLRHMVDDKIHARARGPMQVLTRQPVEGRSRDGGLRFGEMERDCMIA
HGAASFLKERLMEASDAFRVHICGICGLMTVIAKLNHNQFECKGCDNKIDIYQIHIPYAA
KLLFQELMAMNITPRLYTDRSRDF
Sequence of entity 3 (C), FASTA
>9KDN_3 DNA-directed RNA polymerase II subunit RPB3 (chains C)
MSEEGPQVKIREASKDNVDFILSNVDLAMANSLRRVMIAEIPTLAIDSVEVETNTTVLAD
EFIAHRLGLIPLQSMDIEQLEYSRDCFCEDHCDKCSVVLTLQAFGESESTTNVYSKDLVI
VSNLMGRNIGHPIIQDKEGNGVLICKLRKGQELKLTCVAKKGIAKEHAKWGPAAAIEFEY
DPWNKLKHTDYWYEQDSAKEWPQSKNCEYEDPPNEGDPFDYKAQADTFYMNVESVGSIPV
DQVVVRGIDTLQKKVASILLALTQMDQDKVNFASGDNNTASNMLGSNEDVMMTGAEQDPY
SNASQMGNTGSGGYDNAW
Sequence of entity 4 (D), FASTA
>9KDN_4 DNA-directed RNA polymerase II subunit RPB4 (chains D)
MNVSTSTFQTRRRRLKKVEEEENAATLQLGQEFQLKQINHQGEEEELIALNLSEARLVIK
EALVERRRAFKRSQKKHKKKHLKHENANDETTAVEDEDDDLDEDDVNADDDDFMHSETRE
KELESIDVLLEQTTGGNNKDLKNTMQYLTNFSRFRDQETVGAVIQLLKSTGLHPFEVAQL
GSLACDTADEAKTLIPSLNNKISDDELERILKELSNLETLY
Sequence of entity 5 (E), FASTA
>9KDN_5 DNA-directed RNA polymerases I, II, and III subunit RPABC1 (chains E)
MDQENERNISRLWRAFRTVKEMVKDRGYFITQEEVELPLEDFKAKYCDSMGRPQRKMMSF
QANPTEESISKFPDMGSLWVEFCDEPSVGVKTMKTFVIHIQEKNFQTGIFVYQNNITPSA
MKLVPSIPPATIETFNEAALVVNITHHELVPKHIRLSSDEKRELLKRYRLKESQLPRIQR
ADPVALYLGLKRGEVVKIIRKSETSGRYASYRICM
Sequence of entity 6 (F), FASTA
>9KDN_6 DNA-directed RNA polymerases I, II, and III subunit RPABC2 (chains F)
MSDYEEAFNDGNENFEDFDVEHFSDEETYEEKPQFKDGETTDANGKTIVTGGNGPEDFQQ
HEQIRRKTLKEKAIPKDQRATTPYMTKYERARILGTRALQISMNAPVFVDLEGETDPLRI
AMKELAEKKIPLVIRRYLPDGSFEDWSVEELIVDL
Sequence of entity 7 (G), FASTA
>9KDN_7 DNA-directed RNA polymerase II subunit RPB7 (chains G)
MFFIKDLSLNITLHPSFFGPRMKQYLKTKLLEEVEGSCTGKFGYILCVLDYDNIDIQRGR
ILPTDGSAEFNVKYRAVVFKPFKGEVVDGTVVSCSQHGFEVQVGPMKVFVTKHLMPQDLT
FNAGSNPPSYQSSEDVITIKSRIRVKIEGCISQVSSIHAIGSIKEDYLGAI
Sequence of entity 8 (H), FASTA
>9KDN_8 DNA-directed RNA polymerases I, II, and III subunit RPABC3 (chains H)
MSNTLFDDIFQVSEVDPGRYNKVCRIEAASTTQDQCKLTLDINVELFPVAAQDSLTVTIA
SSLNLEDTPANDSSATRSWRPPQAGDRSLADDYDYVMYGTAYKFEEVSKDLIAVYYSFGG
LLMRLEGNYRNLNNLKQENAYLLIRR
Sequence of entity 9 (I), FASTA
>9KDN_9 DNA-directed RNA polymerase II subunit RPB9 (chains I)
MTTFRFCRDCNNMLYPREDKENNRLLFECRTCSYVEEAGSPLVYRHELITNIGETAGVVQ
DIGSDPTLPRSDRECPKCHSRENVFFQSQQRRKDTSMVLFFVCLSCSHIFTSDQKNKRTQ
FS
Sequence of entity 10 (J), FASTA
>9KDN_10 DNA-directed RNA polymerases I, II, and III subunit RPABC5 (chains J)
MIVPVRCFSCGKVVGDKWESYLNLLQEDELDEGTALSRLGLKRYCCRRMILTHVDLIEKF
LRYNPLEKRD
Sequence of entity 11 (K), FASTA
>9KDN_11 DNA-directed RNA polymerase II subunit RPB11 (chains K)
MNAPDRFELFLLGEGESKLKIDPDTKAPNAVVITFEKEDHTLGNLIRAELLNDRKVLFAA
YKVEHPFFARFKLRIQTTEGYDPKDALKNACNSIINKLGALKTNFETEWNLQTLAADDAF
Sequence of entity 12 (L), FASTA
>9KDN_12 DNA-directed RNA polymerases I, II, and III subunit RPABC4 (chains L)
MSREGFQIPTNLDAAAAGTSQARTATLKYICAECSSKLSLSRTDAVRCKDCGHRILLKAR
TKRLVQFEAR

Ligands and cofactors

IDNameFormulaCopies
MGMagnesium ionMg1
ZNZinc ionZn8

Primary citation

Stepwise transcription stalling by the anti-cancer drug Actinomycin D and insights into short tandem repeat transcription inhibition. Zhao, W., Zhu, L., Liu, Y. et al. Nat Commun (2026) 17. DOI 10.1038/s41467-026-70612-y · PubMed

Other PDB entries of the same protein (UniProt P04050 (AlphaFold model), which also has an AlphaFold model), best resolution first:

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