9CA9: Human SRCAP complex in the unbound state

Cryo-EM structure of the human SRCAP complex in the unbound state (composite structure). Determined by electron microscopy at 3.56 Å resolution. Released 18 Jun 2025.

Method
Electron microscopy
Resolution
3.56 Å
Organism
Homo sapiens
Chains
10
Atoms
28,589
Mol. weight
755.87 kDa
Ligands
ZN, MG, AGS, ADP
Released
18 Jun 2025

Explore 9CA9 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9CA9 contains 196 α-helices and 209 β-strands across 10 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: 31 helices, 13 β-strands

ElementResiduesLengthSheet
β-strand852-85981
α-helix863-87614
α-helix890-90213
α-helix904-9063
α-helix909-9113
β-strand91312
β-strand916-91723
α-helix919-9213
β-strand922-92544
α-helix929-9313
α-helix937-9393
α-helix943-9464
α-helix949-9513
α-helix957-9582
α-helix959-9635
α-helix964-9674
β-strand96815
α-helix971-9799
α-helix981-9899
α-helix1887-191024
α-helix1920-19267
α-helix1937-19382
α-helix1946-19494
α-helix1953-19575
α-helix1962-19687
α-helix1970-19767
β-strand1983-198423
α-helix1986-19883
β-strand1989-199244
α-helix1999-201416
α-helix2015-20217
α-helix2022-20298
β-strand203112
α-helix2036-20405
α-helix2043-205816
β-strand2062-206651
α-helix2069-208214
β-strand2086-208941
α-helix2095-210713
β-strand2113-211751
β-strand2132-213541
α-helix2142-215312
β-strand2161-216881
α-helix2172-21798
Chain B: 4 helices, 6 β-strands
ElementResiduesLengthSheet
β-strand211-220106
β-strand260-26896
α-helix271-2777
α-helix281-2888
β-strand29117
β-strand29817
α-helix2991
β-strand301-30338
β-strand308-31038
α-helix313-33018
Chain C: 21 helices, 21 β-strands
ElementResiduesLengthSheet
β-strand2-879
β-strand12-1769
β-strand23-2649
β-strand29-31310
β-strand39-41310
α-helix42-465
β-strand55-57310
β-strand60-61211
β-strand64-65211
α-helix68-7912
α-helix88-903
β-strand91-9779
α-helix103-1119
α-helix112-1165
β-strand121-12669
α-helix127-13812
β-strand145-150612
β-strand155-160612
β-strand165112
α-helix167-1693
β-strand171-173312
α-helix177-19115
α-helix199-20911
α-helix216-2249
β-strand234-237413
β-strand248-249213
α-helix250-2512
α-helix252-2543
β-strand267-270413
α-helix273-28210
α-helix284-2863
α-helix294-30411
α-helix310-3145
β-strand317-320412
α-helix322-3254
α-helix329-34012
β-strand342114
β-strand349-350212
α-helix358-36811
α-helix372-3754
β-strand377-37829
α-helix379-39315
Chain D: 5 helices, 5 β-strands
ElementResiduesLengthSheet
α-helix21-3414
α-helix84-918
α-helix102-1043
β-strand105112
α-helix112-1154
β-strand116115
β-strand123115
β-strand126-127216
β-strand134-135216
α-helix138-14710
Chain E: 23 helices, 27 β-strands
ElementResiduesLengthSheet
β-strand15117
β-strand26118
α-helix311
β-strand32118
α-helix331
β-strand36119
β-strand39119
α-helix43-5816
β-strand61120
β-strand65-69521
α-helix76-8712
β-strand93-96421
α-helix98-1014
α-helix108-11811
β-strand121-1412122
β-strand156-162722
β-strand167-172622
α-helix174-1829
β-strand189-194622
β-strand199-206822
α-helix207-2093
β-strand21516
β-strand220-221222
α-helix222-2243
β-strand229-2391122
α-helix240-2489
α-helix256-2649
α-helix273-28816
β-strand292-295422
β-strand298-301421
α-helix304-3063
α-helix309-32012
β-strand326-331621
β-strand333123
β-strand336-337224
α-helix3381
β-strand345-346224
α-helix352-3554
β-strand358-362521
α-helix365-3673
α-helix368-38114
β-strand386125
α-helix388-39912
α-helix403-4086
α-helix410-41910
β-strand425125
α-helix427-43610
β-strand438126
α-helix440-44910
β-strand455127
Chain F: 21 helices, 27 β-strands
ElementResiduesLengthSheet
β-strand22128
β-strand33129
α-helix381
β-strand39129
α-helix401
β-strand42-43230
β-strand46-47230
α-helix50-6516
β-strand68117
β-strand72-77626
α-helix83-9412
β-strand100-104526
α-helix105-1084
α-helix115-12410
β-strand127-150246
β-strand158-16476
β-strand169-17466
α-helix176-18510
β-strand191-19666
β-strand202-20766
β-strand21116
α-helix226-2283
β-strand233-243116
α-helix244-2529
α-helix256-2627
α-helix270-28617
β-strand289-29356
β-strand295-299526
α-helix301-3033
β-strand305131
α-helix306-31510
β-strand323-328626
β-strand330127
β-strand332-334332
α-helix3351
β-strand336131
β-strand341-343332
α-helix348-3514
β-strand354-359626
α-helix360-3623
α-helix364-37714
β-strand382133
α-helix384-39613
α-helix399-41517
β-strand421133
α-helix423-43210
β-strand434134
α-helix436-44510
Chain G: 24 helices, 28 β-strands
ElementResiduesLengthSheet
β-strand15135
β-strand26136
α-helix311
β-strand32136
α-helix331
β-strand35-36237
β-strand39-40237
α-helix43-5816
β-strand61128
β-strand65-69534
α-helix76-8712
β-strand93-97534
α-helix98-1014
α-helix108-11912
β-strand120-142236
β-strand152-163126
β-strand166-17276
α-helix176-1827
β-strand189-19466
β-strand199-20686
α-helix207-2093
β-strand214138
β-strand220-22126
α-helix222-2254
β-strand229-239116
α-helix240-2489
α-helix256-2638
α-helix265-2662
α-helix273-28917
β-strand292-29656
β-strand298-302534
α-helix304-3063
β-strand308139
α-helix309-32012
β-strand326-331634
β-strand336-337240
α-helix3381
β-strand339139
β-strand345-346240
α-helix352-3554
β-strand358-362534
α-helix364-3674
α-helix368-38114
β-strand386141
α-helix388-39912
α-helix403-4086
α-helix410-42011
β-strand425141
α-helix427-43610
β-strand438142
α-helix440-44910
β-strand455143
Chain H: 23 helices, 28 β-strands
ElementResiduesLengthSheet
β-strand22144
β-strand33145
α-helix381
β-strand39145
α-helix401
β-strand42-43246
β-strand46-47246
α-helix50-6516
β-strand68135
β-strand72-77642
α-helix83-9311
β-strand100-104542
α-helix105-1084
α-helix115-12511
β-strand127-1482238
β-strand158-164738
β-strand169-174638
α-helix176-1849
β-strand191-196638
β-strand202-207638
α-helix211-2133
β-strand217114
β-strand224138
β-strand22515
α-helix226-2283
β-strand233-2431138
α-helix244-2507
α-helix256-2583
α-helix259-2624
α-helix270-28617
β-strand289-293538
β-strand295-299542
α-helix301-3033
α-helix306-31510
β-strand323-328642
β-strand330143
β-strand333-334247
α-helix3351
β-strand341-342247
α-helix348-3514
β-strand354-359642
α-helix360-3623
α-helix364-37815
β-strand382148
α-helix384-39613
α-helix399-41517
β-strand421148
α-helix423-43210
β-strand434149
α-helix436-44510
β-strand451150

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

Molecules and chains

MoleculeChainsTypeLengthOrganismUniProt
Helicase SRCAPAprotein3230Homo sapiensQ6ZRS2
Vacuolar protein sorting-associated protein 72 homologBprotein364Homo sapiensQ15906 (AlphaFold model)
Actin-related protein 6Cprotein396Homo sapiensQ9GZN1 (AlphaFold model)
Zinc finger HIT domain-containing protein 1Dprotein154Homo sapiensO43257 (AlphaFold model)
RuvB-like 1E, G, Iprotein456Homo sapiensQ9Y265
RuvB-like 2F, H, Jprotein463Homo sapiensQ9Y230
Sequence of entity 1 (A), FASTA
>9CA9_1 Helicase SRCAP (chains A)
MQSSPSPAHPQLPVLQTQMVSDGMTGSNPVSPASSSSPASSGAGGISPQHIAQDSSLDGP
PGPPDGATVPLEGFSLSQAADLANKGPKWEKSHAEIAEQAKHEAEIETRIAELRKEGFWS
LKRLPKVPEPPRPKGHWDYLCEEMQWLSADFAQERRWKRGVARKVVRMVIRHHEEQRQKE
ERARREEQAKLRRIASTMAKDVRQFWSNVEKVVQFKQQSRLEEKRKKALDLHLDFIVGQT
EKYSDLLSQSLNQPLTSSKAGSSPCLGSSSAASSPPPPASRLDDEDGDFQPQEDEEEDDE
ETIEVEEQQEGNDAEAQRREIELLRREGELPLEELLRSLPPQLLEGPSSPSQTPSSHDSD
TRDGPEEGAEEEPPQVLEIKPPPSAVTQRNKQPWHPDEDDEEFTANEEEAEDEEDTIAAE
EQLEGEVDHAMELSELAREGELSMEELLQQYAGAYAPGSGSSEDEDEDEVDANSSDCEPE
GPVEAEEPPQEDSSSQSDSVEDRSEDEEDEHSEEEETSGSSASEESESEESEDAQSQSQA
DEEEEDDDFGVEYLLARDEEQSEADAGSGPPTPGPTTLGPKKEITDIAAAAESLQPKGYT
LATTQVKTPIPLLLRGQLREYQHIGLDWLVTMYEKKLNGILADEMGLGKTIQTISLLAHL
ACEKGNWGPHLIIVPTSVMLNWEMELKRWCPSFKILTYYGAQKERKLKRQGWTKPNAFHV
CITSYKLVLQDHQAFRRKNWRYLILDEAQNIKNFKSQRWQSLLNFNSQRRLLLTGTPLQN
SLMELWSLMHFLMPHVFQSHREFKEWFSNPLTGMIEGSQEYNEGLVKRLHKVLRPFLLRR
VKVDVEKQMPKKYEHVIRCRLSKRQRCLYDDFMAQTTTKETLATGHFMSVINILMQLRKV
CNHPNLFDPRPVTSPFITPGICFSTASLVLRATDVHPLQRIDMGRFDLIGLEGRVSRYEA
DTFLPRHRLSRRVLLEVATAPDPPPRPKPVKMKVNRMLQPVPKQEGRTVVVVNNPRAPLG
PVPVRPPPGPELSAQPTPGPVPQVLPASLMVSASPAGPPLIPASRPPGPVLLPPLQPNSG
SLPQVLPSPLGVLSGTSRPPTPTLSLKPTPPAPVRLSPAPPPGSSSLLKPLTVPPGYTFP
PAAATTTSTTTATATTTAVPAPTPAPQRLILSPDMQARLPSGEVVSIGQLASLAQRPVAN
AGGSKPLTFQIQGNKLTLTGAQVRQLAVGQPRPLQRNVVHLVSAGGQHHLISQPAHVALI
QAVAPTPGPTPVSVLPSSTPSTTPAPTGLSLPLAANQVPPTMVNNTGVVKIVVRQAPRDG
LTPVPPLAPAPRPPSSGLPAVLNPRPTLTPGRLPTPTLGTARAPMPTPTLVRPLLKLVHS
PSPEVSASAPGAAPLTISSPLHVPSSLPGPASSPMPIPNSSPLASPVSSTVSVPLSSSLP
ISVPTTLPAPASAPLTIPISAPLTVSASGPALLTSVTPPLAPVVPAAPGPPSLAPSGASP
SASALTLGLATAPSLSSSQTPGHPLLLAPTSSHVPGLNSTVAPACSPVLVPASALASPFP
SAPNPAPAQASLLAPASSASQALATPLAPMAAPQTAILAPSPAPPLAPLPVLAPSPGAAP
VLASSQTPVPVMAPSSTPGTSLASASPVPAPTPVLAPSSTQTMLPAPVPSPLPSPASTQT
LALAPALAPTLGGSSPSQTLSLGTGNPQGPFPTQTLSLTPASSLVPTPAQTLSLAPGPPL
GPTQTLSLAPAPPLAPASPVGPAPAHTLTLAPASSSASLLAPASVQTLTLSPAPVPTLGP
AAAQTLALAPASTQSPASQASSLVVSASGAAPLPVTMVSRLPVSKDEPDTLTLRSGPPSP
PSTATSFGGPRPRRQPPPPPRSPFYLDSLEEKRKRQRSERLERIFQLSEAHGALAPVYGT
EVLDFCTLPQPVASPIGPRSPGPSHPTFWTYTEAAHRAVLFPQQRLDQLSEIIERFIFVM
PPVEAPPPSLHACHPPPWLAPRQAAFQEQLASELWPRARPLHRIVCNMRTQFPDLRLIQY
DCGKLQTLAVLLRQLKAEGHRVLIFTQMTRMLDVLEQFLTYHGHLYLRLDGSTRVEQRQA
LMERFNADKRIFCFILSTRSGGVGVNLTGADTVVFYDSDWNPTMDAQAQDRCHRIGQTRD
VHIYRLISERTVEENILKKANQKRMLGDMAIEGGNFTTAYFKQQTIRELFDMPLEEPSSS
SVPSAPEEEEETVASKQTHILEQALCRAEDEEDIRAATQAKAEQVAELAEFNENDGFPAG
EGEEAGRPGAEDEEMSRAEQEIAALVEQLTPIERYAMKFLEASLEEVSREELKQAEEQVE
AARKDLDQAKEEVFRLPQEEEEGPGAGDESSCGTGGGTHRRSKKAKAPERPGTRVSERLR
GARAETQGANHTPVISAHQTRSTTTPPRCSPARERVPRPAPRPRPTPASAPAAIPALVPV
PVSAPVPISAPNPITILPVHILPSPPPPSQIPPCSSPACTPPPACTPPPAHTPPPAQTCL
VTPSSPLLLGPPSVPISASVTNLPLGLRPEAELCAQALASPESLELASVASSETSSLSLV
PPKDLLPVAVEILPVSEKNLSLTPSAPSLTLEAGSIPNGQEQEAPDSAEGTTLTVLPEGE
ELPLCVSESNGLELPPSAASDEPLQEPLEADRTSEELTEAKTPTSSPEKPQELVTAEVAA
PSTSSSATSSPEGPSPARPPRRRTSADVEIRGQGTGRPGQPPGPKVLRKLPGRLVTVVEE
KELVRRRRQQRGAASTLVPGVSETSASPGSPSVRSMSGPESSPPIGGPCEAAPSSSLPTP
PQQPFIARRHIELGVTGGGSPENGDGALLAITPPAVKRRRGRPPKKNRSPADAGRGVDEA
PSSTLKGKTNGADPVPGPETLIVADPVLEPQLIPGPQPLGPQPVHRPNPLLSPVEKRRRG
RPPKARDLPIPGTISSAGDGNSESRTQPPPHPSPLTPLPPLLVCPTATVANTVTTVTIST
SPPKRKRGRPPKNPPSPRPSQLPVLDRDSTSVLESCGLGRRRQPQGQGESEGSSSDEDGS
RPLTRLARLRLEAEGMRGRKSGGSMVVAVIQDDLDLADSGPGGLELTPPVVSLTPKLRST
RLRPGSLVPPLETEKLPRKRAGAPVGGSPGLAKRGRLQPPSPLGPEGSVEESEAEASGEE
EEGDGTPRRRPGPRRLVGTTNQGDQRILRSSAPPSLAGPAVSHRGRKAKT
Sequence of entity 2 (B), FASTA
>9CA9_2 Vacuolar protein sorting-associated protein 72 homolog (chains B)
MSLAGGRAPRKTAGNRLSGLLEAEEEDEFYQTTYGGFTEESGDDEYQGDQSDTEDEVDSD
FDIDEGDEPSSDGEAEEPRRKRRVVTKAYKEPLKSLRPRKVNTPAGSSQKAREEKALLPL
ELQDDGSDSRKSMRQSTAEHTRQTFLRVQERQGQSRRRKGPHCERPLTQEELLREAKITE
ELNLRSLETYERLEADKKKQVHKKRKCPGPIITYHSVTVPLVGEPGPKEENVDIEGLDPA
PSVSALTPHAGTGPVNPPARCSRTFITFSDDATFEEWFPQGRPPKVPVREVCPVTHRPAL
YRDPVTDIPYATARAFKIIREAYKKYITAHGLPPTASALGPGPPPPEPLPGSGPRALRQK
IVIK
Sequence of entity 3 (C), FASTA
>9CA9_3 Actin-related protein 6 (chains C)
MTTLVLDNGAYNAKIGYSHENVSVIPNCQFRSKTARLKTFTANQIDEIKDPSGLFYILPF
QKGYLVNWDVQRQVWDYLFGKEMYQVDFLDTNIIITEPYFNFTSIQESMNEILFEEYQFQ
AVLRVNAGALSAHRYFRDNPSELCCIIVDSGYSFTHIVPYCRSKKKKEAIIRINVGGKLL
TNHLKEIISYRQLHVMDETHVINQVKEDVCYVSQDFYRDMDIAKLKGEENTVMIDYVLPD
FSTIKKGFCKPREEMVLSGKYKSGEQILRLANERFAVPEILFNPSDIGIQEMGIPEAIVY
SIQNLPEEMQPHFFKNIVLTGGNSLFPGFRDRVYSEVRCLTPTDYDVSVVLPENPITYAW
EGGKLISENDDFEDMVVTREDYEENGHSVCEEKFDI
Sequence of entity 4 (D), FASTA
>9CA9_4 Zinc finger HIT domain-containing protein 1 (chains D)
MVEKKTSVRSQDPGQRRVLDRAARQRRINRQLEALENDNFQDDPHAGLPQLGKRLPQFDD
DADTGKKKKKTRGDHFKLRFRKNFQALLEEQNLSVAEGPNYLTACAGPPSRPQRPFCAVC
GFPSPYTCVSCGARYCTVRCLGTHQETRCLKWTV
Sequence of entity 5 (E, G, I), FASTA
>9CA9_5 RuvB-like 1 (chains E, G, I)
MKIEEVKSTTKTQRIASHSHVKGLGLDESGLAKQAASGLVGQENAREACGVIVELIKSKK
MAGRAVLLAGPPGTGKTALALAIAQELGSKVPFCPMVGSEVYSTEIKKTEVLMENFRRAI
GLRIKETKEVYEGEVTELTPCETENPMGGYGKTISHVIIGLKTAKGTKQLKLDPSIFESL
QKERVEAGDVIYIEANSGAVKRQGRCDTYATEFDLEAEEYVPLPKGDVHKKKEIIQDVTL
HDLDVANARPQGGQDILSMMGQLMKPKKTEITDKLRGEINKVVNKYIDQGIAELVPGVLF
VDEVHMLDIECFTYLHRALESSIAPIVIFASNRGNCVIRGTEDITSPHGIPLDLLDRVMI
IRTMLYTPQEMKQIIKIRAQTEGINISEEALNHLGEIGTKTTLRYSVQLLTPANLLAKIN
GKDSIEKEHVEEISELFYDAKSSAKILADQQDKYMK
Sequence of entity 6 (F, H, J), FASTA
>9CA9_6 RuvB-like 2 (chains F, H, J)
MATVTATTKVPEIRDVTRIERIGAHSHIRGLGLDDALEPRQASQGMVGQLAARRAAGVVL
EMIREGKIAGRAVLIAGQPGTGKTAIAMGMAQALGPDTPFTAIAGSEIFSLEMSKTEALT
QAFRRSIGVRIKEETEIIEGEVVEIQIDRPATGTGSKVGKLTLKTTEMETIYDLGTKMIE
SLTKDKVQAGDVITIDKATGKISKLGRSFTRARDYDAMGSQTKFVQCPDGELQKRKEVVH
TVSLHEIDVINSRTQGFLALFSGDTGEIKSEVREQINAKVAEWREEGKAEIIPGVLFIDE
VHMLDIESFSFLNRALESDMAPVLIMATNRGITRIRGTSYQSPHGIPIDLLDRLLIVSTT
PYSEKDTKQILRIRCEEEDVEMSEDAYTVLTRIGLETSLRYAIQLITAASLVCRKRKGTE
VQVDDIKRVYSLFLDESRSTQYMKEYQDAFLFNELKGETMDTS

Ligands and cofactors

IDNameFormulaCopies
ZNZinc ionZn2
MGMagnesium ionMg4
AGSPhosphothiophosphoric acid-adenylate esterC10 H16 N5 O12 P3 S1
ADPAdenosine-5'-diphosphateC10 H15 N5 O10 P26

Primary citation

Structural mechanism of histone H2A.Z exchange by human SRCAP-CFDP1 holoenzyme. Park, G., Wu, C., Louder, R.K. Sci Adv (2026) 12:eaei7728-eaei7728. DOI 10.1126/sciadv.aei7728 · PubMed

Other PDB entries of the same protein (UniProt Q6ZRS2), best resolution first:

Browse structure collections

About this viewer

MolViewer shows 9CA9 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.