9K3U: SnRNA-activating protein complex subunit 1

Human RNA Polymerase III de novo transcribing complex 5 (TC5). Determined by electron microscopy at 3.0 Å resolution. Released 16 Apr 2025.

Method: Electron microscopy
Resolution: 3.0 Å
Organism: Homo sapiens
Chains: 26
Atoms: 56,785
Mol. weight: 1398.87 kDa
Ligands: ZN, MG, SF4, GTP
Released: 16 Apr 2025

Explore 9K3U in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9K3U contains 320 α-helices and 318 β-strands across 23 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 1: 7 helices, 2 β-strands

Element	Residues	Length	Sheet
α-helix	5-20	16
α-helix	26-35	10
α-helix	48-65	18
α-helix	72-87	16
α-helix	95-96	2
β-strand	97-100	4	1
α-helix	101-115	15
α-helix	122-131	10
β-strand	135-138	4	1

Chain 3: 17 helices, 23 β-strands

Element	Residues	Length	Sheet
α-helix	22-24	3
β-strand	32-34	3	2
β-strand	38-39	2	2
β-strand	42-43	2	3
α-helix	45-53	9
α-helix	79-88	10
α-helix	97-103	7
α-helix	129-143	15
α-helix	151-161	11
α-helix	166-168	3
α-helix	171-173	3
β-strand	174	1	4
α-helix	175-176	2
β-strand	180-187	8	5
β-strand	203-207	5	5
β-strand	211	1	6
α-helix	212-218	7
α-helix	222-225	4
α-helix	238-239	2
α-helix	243-246	4
β-strand	250-254	5	5
β-strand	257-260	4	5
α-helix	270-280	11
β-strand	289-292	4	5
β-strand	297	1	6
β-strand	302-303	2	3
β-strand	308-313	6	5
β-strand	317-328	12	5
β-strand	336	1	4
β-strand	345	1	5
α-helix	350-352	3
β-strand	353	1	7
α-helix	354	1
β-strand	361	1	7
β-strand	364-367	4	8
β-strand	377-379	3	8
α-helix	381-388	8
β-strand	389	1	9
β-strand	395	1	9
β-strand	400-403	4	8

Chain 4: 14 helices, 2 β-strands

Element	Residues	Length	Sheet
α-helix	163-171	9
α-helix	186-221	36
α-helix	226-247	22
α-helix	263-266	4
α-helix	267-271	5
α-helix	277-286	10
α-helix	296-297	2
α-helix	302-312	11
α-helix	318-324	7
α-helix	330-340	11
α-helix	342-343	2
α-helix	351-363	13
β-strand	366	1	10
β-strand	369	1	10
α-helix	372-377	6
α-helix	384-391	8

Chain A: 70 helices, 59 β-strands

Element	Residues	Length	Sheet
β-strand	5	1	11
β-strand	13-21	9	12
α-helix	25-31	7
β-strand	35	1	13
β-strand	38	1	14
β-strand	42	1	15
α-helix	49	1
β-strand	50	1	15
α-helix	51	1
β-strand	54	1	14
α-helix	58-60	3
β-strand	84-93	10	13
α-helix	95-97	3
α-helix	98-107	10
β-strand	108	1	16
β-strand	115	1	16
α-helix	119-129	11
α-helix	136-152	17
β-strand	155	1	17
β-strand	162	1	17
β-strand	166-168	3	18
β-strand	174-176	3	18
α-helix	186-187	2
α-helix	188-195	8
α-helix	198-203	6
α-helix	205-207	3
β-strand	216-217	2	18
α-helix	220-227	8
α-helix	232-234	3
α-helix	236-238	3
α-helix	247-249	3
β-strand	251-257	7	13
β-strand	266	1	19
β-strand	273-276	4	19
α-helix	278-299	22
α-helix	303-321	19
α-helix	341-345	5
α-helix	353-357	5
β-strand	359-360	2	20
β-strand	364-371	8	21
β-strand	379-383	5	21
α-helix	384-389	6
β-strand	391-395	5	22
α-helix	401-410	10
β-strand	418-422	5	22
β-strand	429-431	3	22
α-helix	437-442	6
β-strand	449-453	5	22
β-strand	459-464	6	21
α-helix	470-472	3
β-strand	473-481	9	21
β-strand	486-488	3	21
α-helix	490-492	3
α-helix	493-496	4
β-strand	504-508	5	21
α-helix	513-522	10
β-strand	524	1	21
β-strand	530	1	23
β-strand	537	1	23
α-helix	546-553	8
β-strand	559	1	24
α-helix	561-569	9
α-helix	574-578	5
α-helix	583-586	4
β-strand	588	1	25
β-strand	592	1	26
β-strand	594	1	25
β-strand	595	1	24
α-helix	597-605	9
β-strand	617-620	4	27
β-strand	637-641	5	27
β-strand	644-647	4	27
α-helix	652-655	4
α-helix	663-671	9
α-helix	673-694	22
α-helix	700-702	3
α-helix	707-732	26
α-helix	738-739	2
α-helix	744-770	27
α-helix	772	1
α-helix	776-783	8
α-helix	789-796	8
α-helix	808-810	3
β-strand	813	1	28
β-strand	816	1	28
α-helix	828-831	4
α-helix	844-879	36
β-strand	883-884	2	29
β-strand	890-891	2	29
β-strand	897-899	3	29
α-helix	902-904	3
β-strand	907	1	30
α-helix	909-911	3
α-helix	921-931	11
α-helix	942-953	12
α-helix	963-986	24
α-helix	998-1002	5
α-helix	1008-1024	17
β-strand	1026	1	30
α-helix	1027-1028	2
α-helix	1033-1047	15
α-helix	1067-1075	9
β-strand	1085-1089	5	31
α-helix	1095-1105	11
β-strand	1108-1109	2	32
β-strand	1114-1122	9	33
β-strand	1125-1132	8	33
α-helix	1134-1140	7
α-helix	1146-1152	7
β-strand	1165-1167	3	33
β-strand	1172-1175	4	33
α-helix	1189-1195	7
β-strand	1200-1202	3	32
β-strand	1210-1215	6	31
β-strand	1222-1227	6	31
α-helix	1232-1237	6
β-strand	1241-1248	8	31
α-helix	1251-1258	8
α-helix	1260-1277	18
α-helix	1284-1294	11
α-helix	1305-1311	7
α-helix	1315-1321	7
α-helix	1324-1334	11
α-helix	1336	1
β-strand	1337-1339	3	12
α-helix	1343-1349	7
α-helix	1356-1359	4
β-strand	1361-1364	4	11
α-helix	1372-1377	6

Chain B: 52 helices, 80 β-strands

Element	Residues	Length	Sheet
α-helix	19-21	3
α-helix	24-28	5
α-helix	29-36	8
α-helix	41-49	9
α-helix	50-54	5
α-helix	55-61	7
β-strand	64-66	3	34
β-strand	74-81	8	34
β-strand	87	1	35
β-strand	95	1	35
α-helix	99-105	7
β-strand	110-120	11	34
β-strand	125-137	13	34
α-helix	138-139	2
α-helix	152-157	6
β-strand	169-171	3	36
β-strand	174-178	5	36
α-helix	179	1
β-strand	180-184	5	37
α-helix	185	1
β-strand	189-193	5	38
β-strand	199-206	8	38
β-strand	211-217	7	38
β-strand	224-226	3	38
β-strand	230	1	39
β-strand	234-235	2	38
α-helix	236-242	7
α-helix	248-255	8
α-helix	259-274	16
α-helix	280-290	11
β-strand	291	1	39
α-helix	292-293	2
α-helix	304-311	8
α-helix	312-316	5
α-helix	329-345	17
α-helix	351-353	3
α-helix	357-359	3
β-strand	360-363	4	37
α-helix	365-391	27
α-helix	402-404	3
α-helix	410-420	11
β-strand	424-426	3	40
β-strand	431-433	3	40
β-strand	437-439	3	36
α-helix	445-452	8
β-strand	454-457	4	37
α-helix	473-475	3
β-strand	479	1	41
β-strand	494-495	2	37
β-strand	496	1	41
β-strand	501-502	2	42
α-helix	509-517	9
β-strand	521	1	43
α-helix	528-532	5
β-strand	536-541	6	43
β-strand	544-550	7	43
α-helix	552-565	14
β-strand	573-577	5	43
β-strand	582-586	5	43
β-strand	592-598	7	42
β-strand	599	1	44
β-strand	604	1	44
α-helix	608-616	9
α-helix	621-626	6
β-strand	630-634	5	42
α-helix	635-640	6
β-strand	643-644	2	42
β-strand	656-657	2	42
α-helix	662-664	3
α-helix	669-671	3
α-helix	675-677	3
α-helix	680-690	11
β-strand	693	1	45
β-strand	708-712	5	46
β-strand	716	1	47
α-helix	723-728	6
α-helix	730-732	3
β-strand	737-743	7	48
β-strand	755-758	4	48
α-helix	759-763	5
β-strand	769-779	11	46
β-strand	781	1	49
β-strand	787	1	49
β-strand	789-790	2	50
α-helix	791-793	3
β-strand	795-796	2	51
β-strand	801-802	2	51
β-strand	809	1	52
β-strand	814	1	53
β-strand	815	1	52
α-helix	816	1
β-strand	820-821	2	46
β-strand	825-826	2	54
β-strand	828	1	53
β-strand	830-833	4	50
β-strand	851-853	3	50
β-strand	857-858	2	54
β-strand	864-873	10	46
α-helix	878	1
β-strand	879-889	11	46
β-strand	896-898	3	55
β-strand	905-906	2	55
β-strand	907-911	5	48
β-strand	918-919	2	56
β-strand	927-929	3	48
α-helix	933-937	5
α-helix	940-955	16
α-helix	969-979	11
β-strand	986-987	2	48
β-strand	989-990	2	56
β-strand	997	1	56
α-helix	998	1
β-strand	1002-1009	8	48
β-strand	1010-1011	2	55
β-strand	1012	1	45
α-helix	1016-1019	4
β-strand	1021-1023	3	21
β-strand	1028-1029	2	57
β-strand	1036	1	58
β-strand	1043	1	58
α-helix	1044-1045	2
β-strand	1046-1047	2	20
α-helix	1049-1058	10
α-helix	1061-1065	5
α-helix	1066-1070	5
β-strand	1076-1080	5	59
β-strand	1086-1087	2	59
β-strand	1092	1	60
β-strand	1097	1	60
β-strand	1101-1105	5	59
α-helix	1108-1119	12
β-strand	1123-1130	8	12

Chain C: 14 helices, 25 β-strands

Element	Residues	Length	Sheet
α-helix	3-12	10
β-strand	13-15	3	61
β-strand	16	1	62
β-strand	21	1	62
β-strand	30	1	26
β-strand	33	1	26
α-helix	42-48	7
β-strand	50-57	8	61
β-strand	60-66	7	61
α-helix	70-82	13
β-strand	86-94	9	63
α-helix	103-111	9
β-strand	114	1	63
β-strand	115	1	64
α-helix	119-121	3
α-helix	124-126	3
β-strand	138-145	8	63
β-strand	147-148	2	65
α-helix	159-162	4
β-strand	163-164	2	65
β-strand	167-169	3	66
α-helix	170-172	3
β-strand	174-176	3	63
α-helix	181-184	4
α-helix	186	1
β-strand	192	1	64
β-strand	198-201	4	66
β-strand	207-217	11	63
α-helix	223-225	3
β-strand	228-237	10	61
β-strand	240-241	2	67
β-strand	246	1	68
α-helix	248-256	9
β-strand	262-266	5	68
β-strand	271-275	5	68
α-helix	287-289	3
β-strand	297-298	2	67
β-strand	300-312	13	61
α-helix	318-343	26

Chain D: 8 helices, 1 β-strand

Element	Residues	Length	Sheet
β-strand	3-10	8	11
α-helix	13-29	17
α-helix	33-38	6
α-helix	41-55	15
α-helix	63-74	12
α-helix	80-89	10
α-helix	95	1
α-helix	96-100	5
α-helix	112-121	10

Chain E: 10 helices, 12 β-strands

Element	Residues	Length	Sheet
α-helix	5-24	20
α-helix	30-33	4
α-helix	37-43	7
β-strand	58	1	69
β-strand	62	1	70
β-strand	71	1	70
β-strand	72-75	4	69
β-strand	81-82	2	71
α-helix	84-97	14
β-strand	101-106	6	69
β-strand	109-110	2	71
α-helix	112-119	8
β-strand	126-131	6	69
α-helix	132-135	4
β-strand	147-151	5	72
α-helix	152	1
α-helix	153-163	11
α-helix	171	1
β-strand	172-173	2	72
α-helix	178-183	6
β-strand	190-196	7	72
β-strand	202-209	8	72

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

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
snRNA-activating protein complex subunit 1	1	protein	368	Homo sapiens	Q16533 (AlphaFold model)
snRNA-activating protein complex subunit 3	3	protein	411	Homo sapiens	Q92966 (AlphaFold model)
snRNA-activating protein complex subunit 4	4	protein	1469	Homo sapiens	Q5SXM2 (AlphaFold model)
DNA-directed RNA polymerase III subunit RPC1	A	protein	1390	Homo sapiens	O14802 (AlphaFold model)
DNA-directed RNA polymerase III subunit RPC2	B	protein	1133	Homo sapiens	Q9NW08
DNA-directed RNA polymerases I and III subunit RPAC1	C	protein	346	Homo sapiens	O15160
DNA-directed RNA polymerase III subunit RPC9	D	protein	148	Homo sapiens	O75575
DNA-directed RNA polymerases I, II, and III subunit RPABC1	E	protein	210	Homo sapiens	P19388
DNA-directed RNA polymerases I, II, and III subunit RPABC2	F	protein	127	Homo sapiens	P61218
DNA-directed RNA polymerase III subunit RPC8	G	protein	204	Homo sapiens	Q9Y535
DNA-directed RNA polymerases I, II, and III subunit RPABC3	H	protein	150	Homo sapiens	P52434
DNA-directed RNA polymerase III subunit RPC10	I	protein	108	Homo sapiens	Q9Y2Y1

14 more molecules are not listed.

Sequence of entity 1 (1), FASTA

>9K3U_1 snRNA-activating protein complex subunit 1 (chains 1)
MGTPPGLQTDCEALLSRFQETDSVRFEDFTELWRNMKFGTIFCGRMRNLEKNMFTKEALA
LAWRYFLPPYTFQIRVGALYLLYGLYNTQLCQPKQKIRVALKDWDEVLKFQQDLVNAQHF
DAAYIFRKLRLDRAFHFTAMPKLLSYRMKKKIHRAEVTEEFKDPSDRVMKLITSDVLEEM
LNVHDHYQNMKHVISVDKSKPDKALSLIKDDFFDNIKNIVLEHQQWHKDRKNPSLKSKTN
DGEEKMEGNSQETERCERAESLAKIKSKAFSVVIQASKSRRHRQVKLDSSDSDSASGQGQ
VKATRKKEKKERLKPAGRKMSLRNKGNVQNIHKEDKPLSLSMPVITEEEENESLSGTEFT
ASKKRRKH

Sequence of entity 2 (3), FASTA

>9K3U_2 snRNA-activating protein complex subunit 3 (chains 3)
MAEGSRGGPTCSGVGGRQDPVSGSGGCNFPEYELPELNTRAFHVGAFGELWRGRLRGAGD
LSLREPPASALPGSQAADSDREDAAVARDLDCSLEAAAELRAVCGLDKLKCLEDGEDPEV
IPENTDLVTLGVRKRFLEHREETITIDRACRQETFVYEMESHAIGKKPENSADMIEEGEL
ILSVNILYPVIFHKHKEHKPYQTMLVLGSQKLTQLRDSIRCVSDLQIGGEFSNTPDQAPE
HISKDLYKSAFFYFEGTFYNDKRYPECRDLSRTIIEWSESHDRGYGKFQTARMEDFTFND
LCIKLGFPYLYCHQGDCEHVIVITDIRLVHHDDCLDRTLYPLLIKKHWLWTRKCFVCKMY
TARWVTNNDSFAPEDPCFFCDVCFRMLHYDSEGNKLGEFLAYPYVDPGTFN

Sequence of entity 3 (4), FASTA

>9K3U_3 snRNA-activating protein complex subunit 4 (chains 4)
MDVDAEREKITQEIKELERILDPGSSGSHVEISESSLESDSEADSLPSEDLDPADPPISE
EERWGEASNDEDDPKDKTLPEDPETCLQLNMVYQEVIQEKLAEANLLLAQNREQQEELMR
DLAGSKGTKVKDGKSLPPSTYMGHFMKPYFKDKVTGVGPPANEDTREKAAQGIKAFEELL
VTKWKNWEKALLRKSVVSDRLQRLLQPKLLKLEYLHQKQSKVSSELERQALEKQGREAEK
EIQDINQLPEEALLGNRLDSHDWEKISNINFEGSRSAEEIRKFWQNSEHPSINKQEWSRE
EEERLQAIAAAHGHLEWQKIAEELGTSRSAFQCLQKFQQHNKALKRKEWTEEEDRMLTQL
VQEMRVGSHIPYRRIVYYMEGRDSMQLIYRWTKSLDPGLKKGYWAPEEDAKLLQAVAKYG
EQDWFKIREEVPGRSDAQCRDRYLRRLHFSLKKGRWNLKEEEQLIELIEKYGVGHWAKIA
SELPHRSGSQCLSKWKIMMGKKQGLRRRRRRARHSVRWSSTSSSGSSSGSSGGSSSSSSS
SSEEDEPEQAQAGEGDRALLSPQYMVPDMDLWVPARQSTSQPWRGGAGAWLGGPAASLSP
PKGSSASQGGSKEASTTAAAPGEETSPVQVPARAHGPVPRSAQASHSADTRPAGAEKQAL
EGGRRLLTVPVETVLRVLRANTAARSCTQKEQLRQPPLPTSSPGVSSGDSVARSHVQWLR
HRATQSGQRRWRHALHRRLLNRRLLLAVTPWVGDVVVPCTQASQRPAVVQTQADGLREQL
QQARLASTPVFTLFTQLFHIDTAGCLEVVRERKALPPRLPQAGARDPPVHLLQASSSAQS
TPGHLFPNVPAQEASKSASHKGSRRLASSRVERTLPQASLLASTGPRPKPKTVSELLQEK
RLQEARAREATRGPVVLPSQLLVSSSVILQPPLPHTPHGRPAPGPTVLNVPLSGPGAPAA
AKPGTSGSWQEAGTSAKDKRLSTMQALPLAPVFSEAEGTAPAASQAPALGPGQISVSCPE
SGLGQSQAPAASRKQGLPEAPPFLPAAPSPTPLPVQPLSLTHIGGPHVATSVPLPVTWVL
TAQGLLPVPVPAVVSLPRPAGTPGPAGLLATLLPPLTETRAAQGPRAPALSSSWQPPANM
NREPEPSCRTDTPAPPTHALSQSPAEADGSVAFVPGEAQVAREIPEPRTSSHADPPEAEP
PWSGRLPAFGGVIPATEPRGTPGSPSGTQEPRGPLGLEKLPLRQPGPEKGALDLEKPPLP
QPGPEKGALDLGLLSQEGEAATQQWLGGQRGVRVPLLGSRLPYQPPALCSLRALSGLLLH
KKALEHKATSLVVGGEAERPAGALQASLGLVRGQLQDNPAYLLLRARFLAAFTLPALLAT
LAPQGVRTTLSVPSRVGSESEDEDLLSELELADRDGQPGCTTATCPIQGAPDSGKCSASS
CLDTSNDPDDLDVLRTRHARHTRKRRRLV

Sequence of entity 4 (A), FASTA

>9K3U_4 DNA-directed RNA polymerase III subunit RPC1 (chains A)
MVKEQFRETDVAKKISHICFGMKSPEEMRQQAHIQVVSKNLYSQDNQHAPLLYGVLDHRM
GTSEKDRPCETCGKNLADCLGHYGYIDLELPCFHVGYFRAVIGILQMICKTCCHIMLSQE
EKKQFLDYLKRPGLTYLQKRGLKKKISDKCRKKNICHHCGAFNGTVKKCGLLKIIHEKYK
TNKKVVDPIVSNFLQSFETAIEHNKEVEPLLGRAQENLNPLVVLNLFKRIPAEDVPLLLM
NPEAGKPSDLILTRLLVPPLCIRPSVVSDLKSGTNEDDLTMKLTEIIFLNDVIKKHRISG
AKTQMIMEDWDFLQLQCALYINSELSGIPLNMAPKKWTRGFVQRLKGKQGRFRGNLSGKR
VDFSGRTVISPDPNLRIDEVAVPVHVAKILTFPEKVNKANINFLRKLVQNGPEVHPGANF
IQQRHTQMKRFLKYGNREKMAQELKYGDIVERHLIDGDVVLFNRQPSLHKLSIMAHLARV
KPHRTFRFNECVCTPYNADFDGDEMNLHLPQTEEAKAEALVLMGTKANLVTPRNGEPLIA
AIQDFLTGAYLLTLKDTFFDRAKACQIIASILVGKDEKIKVRLPPPTILKPVTLWTGKQI
FSVILRPSDDNPVRANLRTKGKQYCGKGEDLCANDSYVTIQNSELMSGSMDKGTLGSGSK
NNIFYILLRDWGQNEAADAMSRLARLAPVYLSNRGFSIGIGDVTPGQGLLKAKYELLNAG
YKKCDEYIEALNTGKLQQQPGCTAEETLEALILKELSVIRDHAGSACLRELDKSNSPLTM
ALCGSKGSFINISQMIACVGQQAISGSRVPDGFENRSLPHFEKHSKLPAAKGFVANSFYS
GLTPTEFFFHTMAGREGLVDTAVKTAETGYMQRRLVKSLEDLCSQYDLTVRSSTGDIIQF
IYGGDGLDPAAMEGKDEPLEFKRVLDNIKAVFPCPSEPALSKNELILTTESIMKKSEFLC
CQDSFLQEIKKFIKGVSEKIKKTRDKYGINDNGTTEPRVLYQLDRITPTQVEKFLETCRD
KYMRAQMEPGSAVGALCAQSIGEPGTQMTLKTFHFAGVASMNITLGVPRIKEIINASKAI
STPIITAQLDKDDDADYARLVKGRIEKTLLGEISEYIEEVFLPDDCFILVKLSLERIRLL
RLEVNAETVRYSICTSKLRVKPGDVAVHGEAVVCVTPRENSKSSMYYVLQFLKEDLPKVV
VQGIPEVSRAVIHIDEQSGKEKYKLLVEGDNLRAVMATHGVKGTRTTSNNTYEVEKTLGI
EAARTTIINEIQYTMVNHGMSIDRRHVMLLSDLMTYKGEVLGITRFGLAKMKESVLMLAS
FEKTADHLFDAAYFGQKDSVCGVSECIIMGIPMNIGTGLFKLLHKADRDPNPPKRPLIFD
TNEFHIPLVT

Sequence of entity 5 (B), FASTA

>9K3U_5 DNA-directed RNA polymerase III subunit RPC2 (chains B)
MDVLAEEFGNLTPEQLAAPIPTVEEKWRLLPAFLKVKGLVKQHIDSFNYFINVEIKKIMK
ANEKVTSDADPMWYLKYLNIYVGLPDVEESFNVTRPVSPHECRLRDMTYSAPITVDIEYT
RGSQRIIRNALPIGRMPIMLRSSNCVLTGKTPAEFAKLNECPLDPGGYFIVKGVEKVILI
QEQLSKNRIIVEADRKGAVGASVTSSTHEKKSRTNMAVKQGRFYLRHNTLSEDIPIVIIF
KAMGVESDQEIVQMIGTEEHVMAAFGPSLEECQKAQIFTQMQALKYIGNKVRRQRMWGGG
PKKTKIEEARELLASTILTHVPVKEFNFRAKCIYTAVMVRRVILAQGDNKVDDRDYYGNK
RLELAGQLLSLLFEDLFKKFNSEMKKIADQVIPKQRAAQFDVVKHMRQDQITNGMVNAIS
TGNWSLKRFKMDRQGVTQVLSRLSYISALGMMTRISSQFEKTRKVSGPRSLQPSQWGMLC
PSDTPEGEACGLVKNLALMTHITTDMEDGPIVKLASNLGVEDVNLLCGEELSYPNVFLVF
LNGNILGVIRDHKKLVNTFRLMRRAGYINEFVSISTNLTDRCVYISSDGGRLCRPYIIVK
KQKPAVTNKHMEELAQGYRNFEDFLHESLVEYLDVNEENDCNIALYEHTINKDTTHLEIE
PFTLLGVCAGLIPYPHHNQSPRNTYQCAMGKQAMGTIGYNQRNRIDTLMYLLAYPQKPMV
KTKTIELIEFEKLPAGQNATVAVMSYSGYDIEDALVLNKASLDRGFGRCLVYKNAKCTLK
RYTNQTFDKVMGPMLDAATRKPIWRHEILDADGICSPGEKVENKQVLVNKSMPTVTQIPL
EGSNVPQQPQYKDVPITYKGATDSYIEKVMISSNAEDAFLIKMLLRQTRRPEIGDKFSSR
HGQKGVCGLIVPQEDMPFCDSGICPDIIMNPHGFPSRMTVGKLIELLAGKAGVLDGRFHY
GTAFGGSKVKDVCEDLVRHGYNYLGKDYVTSGITGEPLEAYIYFGPVYYQKLKHMVLDKM
HARARGPRAVLTRQPTEGRSRDGGLRLGEMERDCLIGYGASMLLLERLMISSDAFEVDVC
GQCGLLGYSGWCHYCKSSCHVSSLRIPYACKLLFQELQSMNIIPRLKLSKYNE

Sequence of entity 6 (C), FASTA

>9K3U_6 DNA-directed RNA polymerases I and III subunit RPAC1 (chains C)
MAASQAVEEMRSRVVLGEFGVRNVHTTDFPGNYSGYDDAWDQDRFEKNFRVDVVHMDENS
LEFDMVGIDAAIANAFRRILLAEVPTMAVEKVLVYNNTSIVQDEILAHRLGLIPIHADPR
LFEYRNQGDEEGTEIDTLQFRLQVRCTRNPHAAKDSSDPNELYVNHKVYTRHMTWIPLGN
QADLFPEGTIRPVHDDILIAQLRPGQEIDLLMHCVKGIGKDHAKFSPVATASYRLLPDIT
LLEPVEGEAAEELSRCFSPGVIEVQEVQGKKVARVANPRLDTFSREIFRNEKLKKVVRLA
RVRDHYIFSVESTGVLPPDVLVSEAIKVLMGKCRRFLDELDAVQMD

Sequence of entity 7 (D), FASTA

>9K3U_7 DNA-directed RNA polymerase III subunit RPC9 (chains D)
MEVKDANSALLSNYEVFQLLTDLKEQRKESGKNKHSSGQQNLNTITYETLKYISKTPCRH
QSPEIVREFLTALKSHKLTKAEKLQLLNHRPVTAVEIQLMVEESEERLTEEQIEALLHTV
TSILPAEPEAEQKKNTNSNVAMDEEDPA

Sequence of entity 8 (E), FASTA

>9K3U_8 DNA-directed RNA polymerases I, II, and III subunit RPABC1 (chains E)
MDDEEETYRLWKIRKTIMQLCHDRGYLVTQDELDQTLEEFKAQSGDKPSEGRPRRTDLTV
LVAHNDDPTDQMFVFFPEEPKVGIKTIKVYCQRMQEENITRALIVVQQGMTPSAKQSLVD
MAPKYILEQFLQQELLINITEHELVPEHVVMTKEEVTELLARYKLRENQLPRIQAGDPVA
RYFGIKRGQVVKIIRPSETAGRYITYRLVQ

Sequence of entity 9 (F), FASTA

>9K3U_9 DNA-directed RNA polymerases I, II, and III subunit RPABC2 (chains F)
MSDNEDNFDGDDFDDVEEDEGLDDLENAEEEGQENVEILPSGERPQANQKRITTPYMTKY
ERARVLGTRALQIAMCAPVMVELEGETDPLLIAMKELKARKIPIIIRRYLPDGSYEDWGV
DELIITD

Sequence of entity 10 (G), FASTA

>9K3U_10 DNA-directed RNA polymerase III subunit RPC8 (chains G)
MFVLVEMVDTVRIPPWQFERKLNDSIAEELNKKLANKVVYNVGLCICLFDITKLEDAYVF
PGDGASHTKVHFRCVVFHPFLDEILIGKIKGCSPEGVHVSLGFFDDILIPPESLQQPAKF
DEAEQVWVWEYETEEGAHDLYMDTGEEIRFRVVDESFVDTSPTGPSSADATTSSEELPKK
EAPYTLVGSISEPGLGLLSWWTSN

Sequence of entity 11 (H), FASTA

>9K3U_11 DNA-directed RNA polymerases I, II, and III subunit RPABC3 (chains H)
MAGILFEDIFDVKDIDPEGKKFDRVSRLHCESESFKMDLILDVNIQIYPVDLGDKFRLVI
ASTLYEDGTLDDGEYNPTDDRPSRADQFEYVMYGKVYRIEGDETSTEAATRLSAYVSYGG
LLMRLQGDANNLHGFEVDSRVYLLMKKLAF

Sequence of entity 12 (I), FASTA

>9K3U_12 DNA-directed RNA polymerase III subunit RPC10 (chains I)
MLLFCPGCGNGLIVEEGQRCHRFACNTCPYVHNITRKVTNRKYPKLKEVDDVLGGAAAWE
NVDSTAESCPKCEHPRAYFMQLQTRSADEPMTTFYKCCNAQCGHRWRD

Ligands and cofactors

ID	Name	Formula	Copies
ZN	Zinc ion	Zn	7
MG	Magnesium ion	Mg	1
SF4	Iron/sulfur cluster	Fe4 S4	1
GTP	Guanosine-5'-triphosphate	C10 H16 N5 O14 P3	1

Primary citation

Structural insights into human Pol III transcription initiation in action. Wang, Q., Ren, Y., Jin, Q. et al. Nature (2025) 643:1127-1134. DOI 10.1038/s41586-025-09093-w · PubMed

Other PDB entries of the same protein (UniProt Q16533 (AlphaFold model), which also has an AlphaFold model), best resolution first:

7ZWD 3.0 Å, Structure of SNAPc containing Pol II pre-initiation complex bound to U5 snRNA promoter…
7ZX8 3.0 Å, Structure of SNAPc containing Pol II pre-initiation complex bound to U1 snRNA promoter…
7ZWC 3.2 Å, Structure of SNAPc:TBP-TFIIA-TFIIB sub-complex bound to U5 snRNA promoter
9FSO 3.28 Å, Human RNA Polymerase III Class III Open Pre-initiation Complex 1 (OC1)
9LXN 3.3 Å, Human RNA Polymerase III de novo transcribing complex 5 (TC5)(without 3'dATP)
9FSP 3.39 Å, RNA Polymerase III Class III Open Pre-initation Complex 2 (OC2)
7ZX7 3.4 Å, Structure of SNAPc containing Pol II pre-initiation complex bound to U1 snRNA promoter…
8IUH 3.4 Å, RNA polymerase III pre-initiation complex open complex 1
7XUR 3.49 Å, The cryo-EM structure of human mini-SNAPc in complex with hU6-1 PSE
7ZXE 3.5 Å, Structure of SNAPc containing Pol II pre-initiation complex bound to U1 snRNA promoter…
9K3V 3.5 Å, Human RNA Polymerase III de novo transcribing complex 4 (TC4)
9FSQ 3.51 Å, RNA Polymerase III Class III Melting Pre-Initiation Complex (MC)

Browse structure collections

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