7B7U: Mammalian RNA polymerase II

Cryo-EM structure of mammalian RNA polymerase II in complex with human RPAP2. Determined by electron microscopy at 2.8 Å resolution. Released 19 May 2021.

Method: Electron microscopy
Resolution: 2.8 Å
Organisms: Sus scrofa domesticus, Homo sapiens
Chains: 12
Atoms: 25,091
Mol. weight: 553.88 kDa
Ligands: ZN
Released: 19 May 2021

Explore 7B7U in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

7B7U contains 137 α-helices and 163 β-strands across 12 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: 45 helices, 46 β-strands

Element	Residues	Length	Sheet
β-strand	365	1	1
β-strand	367-369	3	2
β-strand	377-381	5	2
α-helix	382-387	6
β-strand	389-393	5	3
α-helix	399-408	10
β-strand	416-420	5	3
β-strand	426-428	3	3
β-strand	445-449	5	3
β-strand	455-457	3	2
β-strand	471-477	7	2
β-strand	482-484	3	2
β-strand	501	1	1
β-strand	504	1	2
α-helix	509-518	10
α-helix	542-548	7
α-helix	557-565	9
α-helix	573-577	5
β-strand	579-581	3	4
β-strand	585	1	4
α-helix	588-595	8
β-strand	602-604	3	5
α-helix	612-615	4
β-strand	628-630	3	5
β-strand	635-637	3	5
α-helix	642-645	4
α-helix	652-660	9
α-helix	662-683	22
β-strand	686	1	6
α-helix	689-692	4
α-helix	696-722	27
α-helix	726-728	3
α-helix	733-759	27
α-helix	765-772	8
α-helix	778-785	8
β-strand	789-790	2	7
β-strand	793	1	8
β-strand	796	1	8
β-strand	802	1	9
β-strand	805	1	9
β-strand	822-823	2	7
α-helix	833-867	35
β-strand	872-873	2	10
β-strand	879-880	2	10
β-strand	886-888	3	10
α-helix	891-893	3
β-strand	896	1	11
β-strand	902-905	4	12
α-helix	913-919	7
α-helix	929-933	5
β-strand	934	1	13
α-helix	936-944	9
α-helix	946-969	24
α-helix	971-973	3
β-strand	976-979	4	12
α-helix	983-993	11
β-strand	1002	1	13
α-helix	1006-1019	14
α-helix	1028-1048	21
α-helix	1051-1053	3
α-helix	1054-1058	5
α-helix	1062-1079	18
β-strand	1080	1	11
α-helix	1087-1096	10
α-helix	1097-1101	5
α-helix	1121-1128	8
β-strand	1140-1141	2	14
α-helix	1146-1149	4
α-helix	1151-1159	9
β-strand	1164	1	15
β-strand	1170-1177	8	16
α-helix	1187-1189	3
α-helix	1190-1197	8
α-helix	1204-1206	3
β-strand	1207	1	17
β-strand	1210-1216	7	16
α-helix	1218-1223	6
α-helix	1228-1239	12
β-strand	1245-1247	3	16
β-strand	1256-1259	4	16
β-strand	1262	1	17
α-helix	1281-1292	12
β-strand	1299	1	15
β-strand	1306-1310	5	14
β-strand	1319-1322	4	18
β-strand	1328-1331	4	18
β-strand	1335-1339	5	14
α-helix	1343-1348	6
α-helix	1362-1368	7
α-helix	1371-1387	17
α-helix	1395-1404	10

Chain B: 47 helices, 59 β-strands

Element	Residues	Length	Sheet
α-helix	22-36	15
α-helix	41-49	9
α-helix	50-54	5
α-helix	56-58	3
α-helix	63-64	2
β-strand	65-67	3	19
β-strand	83-93	11	19
β-strand	97-99	3	20
β-strand	105-107	3	20
α-helix	110-115	6
β-strand	121-133	13	19
β-strand	139-153	15	19
α-helix	168-171	4
β-strand	185-187	3	21
β-strand	190-193	4	21
α-helix	194-195	2
β-strand	196-200	5	22
α-helix	201	1
β-strand	204-208	5	23
β-strand	215-222	8	23
β-strand	234-240	7	23
β-strand	256-259	4	23
β-strand	267-268	2	23
α-helix	269-276	8
α-helix	281-288	8
α-helix	295-306	12
α-helix	314-322	9
α-helix	332-341	10
α-helix	342-346	5
α-helix	358-376	19
α-helix	381-384	4
α-helix	388-390	3
β-strand	391-394	4	22
α-helix	396-422	27
α-helix	431-434	4
α-helix	437-449	13
β-strand	468-469	2	21
α-helix	470	1
α-helix	475-482	8
β-strand	485-486	2	22
α-helix	501-502	2
α-helix	503-505	3
β-strand	509	1	24
β-strand	523-524	2	22
β-strand	526	1	24
β-strand	531-532	2	25
α-helix	539-547	9
β-strand	552	1	26
α-helix	553-555	3
α-helix	560-563	4
β-strand	565-569	5	26
β-strand	572-577	6	26
α-helix	580-593	14
β-strand	602-606	5	26
β-strand	611-615	5	26
β-strand	621-627	7	25
β-strand	628	1	27
β-strand	633	1	27
α-helix	637-644	8
α-helix	653-658	6
β-strand	662-666	5	25
α-helix	667-670	4
β-strand	675-676	2	25
β-strand	695-696	2	25
α-helix	700-703	4
α-helix	708-710	3
α-helix	714-716	3
α-helix	719-730	12
β-strand	732	1	28
β-strand	748-751	4	29
β-strand	755	1	30
β-strand	759-760	2	31
α-helix	763-766	4
β-strand	776-782	7	32
β-strand	783	1	6
β-strand	794-797	4	32
α-helix	798-803	6
β-strand	808-817	10	29
β-strand	828-829	2	33
β-strand	853	1	34
α-helix	854-855	2
β-strand	859-860	2	29
β-strand	867	1	34
β-strand	869-871	3	33
β-strand	890-891	2	33
β-strand	894	1	34
β-strand	902-911	10	29
β-strand	917-927	11	29
β-strand	934-937	4	32
β-strand	943-949	7	32
β-strand	956-957	2	35
β-strand	965-967	3	32
α-helix	969-971	3
α-helix	978-993	16
α-helix	996	1
β-strand	997-998	2	31
α-helix	1008-1016	9
β-strand	1025-1026	2	32
β-strand	1028-1029	2	35
α-helix	1035	1
β-strand	1036	1	35
α-helix	1037	1
α-helix	1040	1
β-strand	1041-1050	10	32
β-strand	1051	1	28
α-helix	1055-1059	5

Chain C: 10 helices, 12 β-strands

Element	Residues	Length	Sheet
β-strand	8-14	7	36
β-strand	18-24	7	36
α-helix	28-40	13
β-strand	44-55	12	37
α-helix	61-69	9
β-strand	73	1	38
α-helix	78-81	4
β-strand	99-106	8	37
α-helix	112	1
β-strand	113-116	4	39
α-helix	117-119	3
β-strand	121-122	2	37
β-strand	129	1	38
β-strand	149-153	5	39
β-strand	158-168	11	37
α-helix	174-176	3
β-strand	179-185	7	36
α-helix	200-202	3
α-helix	204-206	3
α-helix	218-220	3
β-strand	229-235	7	36
α-helix	241-270	30

Chain E: 10 helices, 10 β-strands

Element	Residues	Length	Sheet
α-helix	4-23	20
β-strand	26	1	40
α-helix	30-33	4
α-helix	37-43	7
α-helix	49-51	3
β-strand	60-61	2	41
β-strand	64	1	40
β-strand	73-75	3	41
α-helix	84-96	13
β-strand	101-105	5	41
α-helix	112-120	9
β-strand	126-130	5	41
α-helix	134-136	3
α-helix	139-141	3
β-strand	147-150	4	42
α-helix	153-163	11
β-strand	172-173	2	42
α-helix	178-183	6
β-strand	190-197	8	42
β-strand	201-209	9	42

Chain F: 3 helices, 2 β-strands

Element	Residues	Length	Sheet
α-helix	59-74	16
α-helix	89-98	10
β-strand	105-107	3	43
β-strand	117-119	3	43
α-helix	120-122	3

Chain H: 2 helices, 10 β-strands

Element	Residues	Length	Sheet
β-strand	4-14	11	4
β-strand	25-32	8	4
β-strand	38-44	7	4
β-strand	55-61	7	4
α-helix	84-87	4
β-strand	90-100	11	4
β-strand	104	1	44
β-strand	107	1	44
β-strand	113-118	6	4
β-strand	121-126	6	4
α-helix	131-133	3
β-strand	139-147	9	4

Chain I: 3 helices, 10 β-strands

Element	Residues	Length	Sheet
β-strand	16	1	45
β-strand	23	1	45
β-strand	25-29	5	46
β-strand	34-38	5	46
β-strand	45-47	3	46
β-strand	52-56	5	16
α-helix	64-67	4
α-helix	70-74	5
β-strand	80-81	2	47
β-strand	94-97	4	47
α-helix	109-110	2
β-strand	111-114	4	47
β-strand	122-124	3	47

Chain J: 6 helices, 1 β-strand

Element	Residues	Length	Sheet
α-helix	3-4	2
α-helix	18-26	9
α-helix	31-37	7
α-helix	43-51	9
β-strand	52	1	30
α-helix	56-60	5
α-helix	63-64	2

4 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
DNA-directed RNA polymerase subunit	A	protein	1970	Sus scrofa domesticus	I3LJR4
DNA-directed RNA polymerase subunit beta	B	protein	1174	Sus scrofa domesticus	I3LGP4 (AlphaFold model)
DNA-directed RNA polymerase II subunit RPB3	C	protein	271	Sus scrofa domesticus	I3LCH3 (AlphaFold model)
DNA-directed RNA polymerase II subunit E	E	protein	210	Sus scrofa domesticus	I3LSI7 (AlphaFold model)
DNA-directed RNA polymerase II subunit F	F	protein	127	Sus scrofa domesticus	A0A4X1VEK9
DNA-directed RNA polymerases I, II, and III subunit RPABC3	H	protein	150	Sus scrofa domesticus	I3LCB2
DNA-directed RNA polymerase II subunit RPB9	I	protein	125	Sus scrofa domesticus	P60899
Uncharacterized Protein	J	protein	67	Sus scrofa domesticus	A0A4X1VYD0
RNA_pol_L_2 domain-containing protein	K	protein	117	Sus scrofa domesticus	F1RKE4
RNA polymerase II subunit K	L	protein	58	Sus scrofa domesticus	A0A4X1TRS6
Putative RNA polymerase II subunit B1 CTD phosphatase RPAP2	M	protein	612	Homo sapiens	Q8IXW5
Unknown	N	protein	30	Homo sapiens

Sequence of entity 1 (A), FASTA

>7B7U_1 DNA-directed RNA polymerase subunit (chains A)
MHGGGPPSGDSACPLRTIKRVQFGVLSPDELKRMSVTEGGIKYPETTEGGRPKLGGLMDP
RQGVIERTGRCQTCAGNMTECPGHFGHIELAKPVFHVGFLVKTMKVLRCVCFFCSKLLVD
SNNPKIKDILAKSKGQPKKRLTHVYDLCKGKNICEGGEEMDNKFGVEQPEGDEDLTKEKG
HGGCGRYQPRIRRSGLELYAEWKHVNEDSQEKKILLSPERVHEIFKRISDEECFVLGMEP
RYARPEWMIVTVLPVPPLSVRPAVVMQGSARNQDDLTHKLADIVKINNQLRRNEQNGAAA
HVIAEDVKLLQFHVATMVDNELPGLPRAMQKSGRPLKSLKQRLKGKEGRVRGNLMGKRVD
FSARTVITPDPNLSIDQVGVPRSIAANMTFAEIVTPFNIDRLQELVRRGNSQYPGAKYII
RDNGDRIDLRFHPKPSDLHLQTGYKVERHMCDGDIVIFNRQPTLHKMSMMGHRVRILPWS
TFRLNLSVTTPYNADFDGDEMNLHLPQSLETRAEIQELAMVPRMIVTPQSNRPVMGIVQD
TLTAVRKFTKRDVFLERGEVMNLLMFLSTWDGKVPQPAILKPRPLWTGKQIFSLIIPGHI
NCIRTHSTHPDDEDSGPYKHISPGDTKVVVENGELIMGILCKKSLGTSAGSLVHISYLEM
GHDITRLFYSNIQTVINNWLLIEGHTIGIGDSIADSKTYQDIQNTIKKAKQDVIEVIEKA
HNNELEPTPGNTLRQTFENQVNRILNDARDKTGSSAQKSLSEYNNFKSMVVSGAKGSKIN
ISQVIAVVGQQNVEGKRIPFGFKHRTLPHFIKDDYGPESRGFVENSYLAGLTPTEFFFHA
MGGREGLIDTAVKTAETGYIQRRLIKSMESVMVKYDATVRNSINQVVQLRYGEDGLAGES
VEFQNLATLKPSNKAFEKKFRFDYTNERALRRTLQEDLVKDVLSNAHIQNELEREFERMR
EDREVLRVIFPTGDSKVVLPCNLLRMIWNAQKIFHINPRLPSDLHPIKVVEGVKELSKKL
VIVNGDDPLSRQAQENATLLFNIHLRSTLCSRRMAEEFRLSGEAFDWLLGEIESKFNQAI
AHPGEMVGALAAQSLGEPATQMTLNTFHYAGVSAKNVTLGVPRLKELINISKKPKTPSLT
VFLLGQSARDAERAKDILCRLEHTTLRKVTANTAIYYDPNPQSTVVAEDQEWVNVYYEMP
DFDVARISPWLLRVELDRKHMTDRKLTMEQIAEKINAGFGDDLNCIFNDDNAEKLVLRIR
IMNSDENKMQEEEEVVDKMDDDVFLRCIESNMLTDMTLQGIEQISKVYMHLPQTDNKKKI
IITEDGEFKALQEWILETDGVSLMRVLSEKDVDPVRTTSNDIVEIFTVLGIEAVRKALER
ELYHVISFDGSYVNYRHLALLCDTMTCRGHLMAITRHGVNRQDTGPLMKCSFEETVDVLM
EAAAHGESDPMKGVSENIMLGQLAPAGTGCFDLLLDAEKCKYGMEIPTNIPGLGAAGPTG
MFFGSAPSPMGGISPAMTPWNQGATPAYGAWSPSVGSGMTPGAAGFSPSAASDASGFSPG
YSPAWSPTPGSPGSPGPSSPYIPSPGGAMSPSYSPTSPAYEPRSPGGYTPQSPSYSPTSP
SYSPTSPSYSPTSPNYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSP
TSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPSYSPTSPS
YSPTSPNYSPTSPNYTPTSPSYSPTSPSYSPTSPNYTPTSPNYSPTSPSYSPTSPSYSPT
SPSYSPSSPRYTPQSPTYTPSSPSYSPSSPSYSPTSPKYTPTSPSYSPSSPEYTPTSPKY
SPTSPKYSPTSPKYSPTSPTYSPTTPKYSPTSPTYSPTSPVYTPTSPKYSPTSPTYSPTS
PKYSPTSPTYSPTSPKGSTYSPTSPGYSPTSPTYSLTSPAISPDDSDEEN

Sequence of entity 2 (B), FASTA

>7B7U_2 DNA-directed RNA polymerase subunit beta (chains B)
MYDADEDMQYDEDDDEITPDLWQEACWIVISSYFDEKGLVRQQLDSFDEFIQMSVQRIVE
DAPPIDLQAEAQHASGEVEEPPRYLLKFEQIYLSKPTHWERDGAPSPMMPNEARLRNLTY
SAPLYVDITKTVIKEGEEQLQTQHQKTFIGKIPIMLRSTYCLLNGLTDRDLCELNECPLD
PGGYFIINGSEKVLIAQEKMATNTVYVFAKKDSKYAYTGECRSCLENSSRPTSTIWVSML
ARGGQGAKKSAIGQRIVATLPYIKQEVPIIIVFRALGFVSDRDILEHIIYDFEDPEMMEM
VKPSLDEAFVIQEQNVALNFIGSRGAKPGVTKEKRIKYAKEVLQKEMLPHVGVSDFCETK
KAYFLGYMVHRLLLAALGRRELDDRDHYGNKRLDLAGPLLAFLFRGMFKNLLKEVRIYAQ
KFIDRGKDFNLELAIKTRIISDGLKYSLATGNWGDQKKAHQARAGVSQVLNRLTFASTLS
HLRRLNSPIGRDGKLAKPRQLHNTLWGMVCPAETPEGHAVGLVKNLALMAYISVGSQPSP
ILEFLEEWSMENLEEISPAAIADATKIFVNGCWVGIHKDPEQLMNTLRKLRRQMDIIVSE
VSMIRDIREREIRIYTDAGRICRPLLIVEKQKLLLKKRHIDQLKEREYNNYSWQDLVASG
VVEYIDTLEEETVMLAMTPDDLQEKEVAYCSTYTHCEIHPSMILGVCASIIPFPDHNQSP
RNTYQSAMGKQAMGVYITNFHVRMDTLAHVLYYPQKPLVTTRSMEYLRFRELPAGINSIV
AIASYTGYNQEDSVIMNRSAVDRGFFRSVFYRSYKEQESKKGFDQEEVFEKPTRETCQGM
RHAIYDKLDDDGLIAPGVRVSGDDVIIGKTVTLPENEDELEGTNRRYTKRDCSTFLRTSE
TGIVDQVMVTLNQEGYKFCKIRVRSVRIPQIGDKFASRHGQKGTCGIQYRQEDMPFTCEG
ITPDIIINPHAIPSRMTIGHLIECLQGKVSANKGEIGDATPFNDAVNVQKISNLLSDYGY
HLRGNEVLYNGFTGRKITSQIFIGPTYYQRLKHMVDDKIHSRARGPIQILNRQPMEGRSR
DGGLRFGEMERDCQIAHGAAQFLRERLFEASDPYQVHVCNLCGIMAIANTRTHTYECRGC
RNKTQISLVRMPYACKLLFQELMSMSIAPRMMSV

Sequence of entity 3 (C), FASTA

>7B7U_3 DNA-directed RNA polymerase II subunit RPB3 (chains C)
MPYANQPTVRITELTDENVKFIIENTDLAVANSIRRVFIAEVPIIAIDWVQIDANSSVLH
DEFIAHRLGLIPLTSDDIVDKLQYSRDCTCEEFCPECSVEFTLDVRCNEDQTRHVTSRDL
ISNSPRVIPVTSRNRDNDPSDYVEQDDILIVKLRKGQELRLRAYAKKGFGKEHAKWNPTA
GVAFEYDPDNALRHTVYPKPEEWPKSEYSELDEDESQAPYDPNGKPERFYYNVESCGSLR
PETIVLSALSGLKKKLSDLQTQLSHEIQSDV

Sequence of entity 4 (E), FASTA

>7B7U_4 DNA-directed RNA polymerase II subunit E (chains E)
MDDEEETYRLWKIRKTIMQLCHDRGYLVTQDELDQTLEEFKAQFGDKPSEGRPRRTDLTV
LVAHNDDPTDQMFVFFPEEPKVGIKTIKVYCQRMQEENITRALIVVQQGMTPSAKQSLVD
MAPKYILEQFLQQELLINITEHELVPEHVVMTKEEVTELLARYKLRENQLPRIQAGDPVA
RYFGIKRGQVVKIIRPSETAGRYITYRLVQ

Sequence of entity 5 (F), FASTA

>7B7U_5 DNA-directed RNA polymerase II subunit F (chains F)
MSDNEDNFDGDDFDDVEEDEGLDDLENAEEEGQENVEILPSGERPQANQKRITTPYMTKY
ERARVLGTRALQIAMCAPVMVELEGETDPLLIAMKELKARKIPIIIRRYLPDGSYEDWGV
DELIISD

Sequence of entity 6 (H), FASTA

>7B7U_6 DNA-directed RNA polymerases I, II, and III subunit RPABC3 (chains H)
MAGILFEDIFDVKDIDPEGKKFDRVSRLHCESESFKMDLILDVNIQIYPVDLGDKFRLVI
ASTLYEDGTLDDGEYNPTDDRPSRADQFEYVMYGKVYRIEGDETSTEAATRLSAYVSYGG
LLMRLQGDANNLHGFEVDSRVYLLMKKLAF

Sequence of entity 7 (I), FASTA

>7B7U_7 DNA-directed RNA polymerase II subunit RPB9 (chains I)
MEPDGTYEPGFVGIRFCQECNNMLYPKEDKENRILLYACRNCDYQQEADNSCIYVNKITH
EVDELTQIIADVSQDPTLPRTEDHPCQKCGHKEAVFFQSHSARAEDAMRLYYVCTAPHCG
HRWTE

Sequence of entity 8 (J), FASTA

>7B7U_8 Uncharacterized Protein (chains J)
MIIPVRCFTCGKIVGNKWEAYLGLLQAEYTEGDALDALGLKRYCCRRMLLAHVDLIEKLL
NYAPLEK

Sequence of entity 9 (K), FASTA

>7B7U_9 RNA_pol_L_2 domain-containing protein (chains K)
MNAPPAFESFLLFEGEKKITINKDTKVPNACLFTINKEDHTLGNIIKSQLLKDPQVLFAG
YKVPHPLEHKIIIRVQTTPDYSPQEAFTNAITDLISELSLLEERFRVAIKDKQEGIE

Sequence of entity 10 (L), FASTA

>7B7U_10 RNA polymerase II subunit K (chains L)
MDTQKDVQPPKQQPMIYICGECHTENEIKSRDPIRCRECGYRIMYKKRTKRLVVFDAR

Sequence of entity 11 (M), FASTA

>7B7U_11 Putative RNA polymerase II subunit B1 CTD phosphatase RPAP2 (chains M)
MADFAGPSSAGRKAGAPRCSRKAAGTKQTSTLKQEDASKRKAELEAAVRKKIEFERKALH
IVEQLLEENITEEFLMECGRFITPAHYSDVVDERSIVKLCGYPLCQKKLGIVPKQKYKIS
TKTNKVYDITERKSFCSNFCYQASKFFEAQIPKTPVWVREEERHPDFQLLKEEQSGHSGE
EVQLCSKAIKTSDIDNPSHFEKQYESSSSSTHSDSSSDNEQDFVSSILPGNRPNSTNIRP
QLHQKSIMKKKAGHKANSKHKDKEQTVVDVTEQLGDCKLDSQEKDATCELPLQKVNTQSS
SNSTLPERLKASENSESEYSRSEITLVGISKKSAEHFKRKFAKSNQVSRSVSSSVQVCPE
VGKRNLLKVLKETLIEWKTEETLRFLYGQNYASVCLKPEASLVKEELDEDDIISDPDSHF
PAWRESQNSLDESLPFRGSGTAIKPLPSYENLKKETEKLNLRIREFYRGRYVLGEETTKS
QDSEEHDSTFPLIDSSSQNQIRKRIVLEKLSKVLPGLLVPLQITLGDIYTQLKNLVRTFR
LTNRNIIHKPAEWTLIAMVLLSLLTPILGIQKHSQEGMVFTRFLDTLLEELHLKNEDLES
LTIIFRTSCLPE

Sequence of entity 12 (N), FASTA

>7B7U_12 Unknown (chains N)
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

Ligands and cofactors

ID	Name	Formula	Copies
ZN	Zinc ion	Zn	6

Primary citation

Cryo-EM structure of mammalian RNA polymerase II in complex with human RPAP2. Fianu, I., Dienemann, C., Aibara, S. et al. Commun Biol (2021) 4:606-606. DOI 10.1038/s42003-021-02088-z · PubMed

Other PDB entries of the same protein (UniProt I3LJR4), best resolution first:

9G0A 3.1 Å, Influenza A/H7N9 polymerase post-cleavage cap-snatching complex
9FYX 3.3 Å, Influenza A/H7N9 polymerase pre-cleavage cap-snatching complex
7PKS 3.6 Å, Structural basis of Integrator-mediated transcription regulation
8RBZ 3.7 Å, Structure of Integrator-PP2A-SOSS-CTD post-termination complex

Browse structure collections

About this viewer

MolViewer shows 7B7U directly in your browser with nothing to install. Switch between cartoon, ball-and-stick, spacefill and surface views, color by chain, secondary structure or B-factor, measure distances, angles and dihedrals, and share or embed the view.