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Protein

Transitional endoplasmic reticulum ATPase

Gene

Vcp

Organism
Mus musculus (Mouse)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Necessary for the fragmentation of Golgi stacks during mitosis and for their reassembly after mitosis. Involved in the formation of the transitional endoplasmic reticulum (tER). The transfer of membranes from the endoplasmic reticulum to the Golgi apparatus occurs via 50-70 nm transition vesicles which derive from part-rough, part-smooth transitional elements of the endoplasmic reticulum (tER). Vesicle budding from the tER is an ATP-dependent process. The ternary complex containing UFD1, VCP and NPLOC4 binds ubiquitinated proteins and is necessary for the export of misfolded proteins from the ER to the cytoplasm, where they are degraded by the proteasome. The NPLOC4-UFD1-VCP complex regulates spindle disassembly at the end of mitosis and is necessary for the formation of a closed nuclear envelope. Regulates E3 ubiquitin-protein ligase activity of RNF19A. Component of the VCP/p97-AMFR/gp78 complex that participates in the final step of the sterol-mediated ubiquitination and endoplasmic reticulum-associated degradation (ERAD) of HMGCR. Involved in endoplasmic reticulum stress-induced pre-emptive quality control, a mechanism that selectively attenuates the translocation of newly synthesized proteins into the endoplasmic reticulum and reroutes them to the cytosol for proteasomal degradation. Also involved in DNA damage response: recruited to double-strand breaks (DSBs) sites in a RNF8- and RNF168-dependent manner and promotes the recruitment of TP53BP1 at DNA damage sites. Recruited to stalled replication forks by SPRTN: may act by mediating extraction of DNA polymerase eta (POLH) to prevent excessive translesion DNA synthesis and limit the incidence of mutations induced by DNA damage. Required for cytoplasmic retrotranslocation of stressed/damaged mitochondrial outer-membrane proteins and their subsequent proteasomal degradation. Essential for the maturation of ubiquitin-containing autophagosomes and the clearance of ubiquitinated protein by autophagy. Acts as a negative regulator of type I interferon production by interacting with DDX58/RIG-I: interaction takes place when DDX58/RIG-I is ubiquitinated via 'Lys-63'-linked ubiquitin on its CARD domains, leading to recruit RNF125 and promote ubiquitination and degradation of DDX58/RIG-I.By similarity

Catalytic activityi

ATP + H2O = ADP + phosphate.By similarity

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Binding sitei348ATPBy similarity1
Binding sitei384ATP2 Publications1

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Nucleotide bindingi247 – 253ATP2 Publications7
Nucleotide bindingi521 – 526ATP2 Publications6

GO - Molecular functioni

  • ADP binding Source: CAFA
  • ATPase activity Source: ParkinsonsUK-UCL
  • ATP binding Source: ParkinsonsUK-UCL
  • BAT3 complex binding Source: MGI
  • deubiquitinase activator activity Source: MGI
  • identical protein binding Source: CAFA
  • K48-linked polyubiquitin binding Source: ParkinsonsUK-UCL
  • lipid binding Source: UniProtKB-KW
  • MHC class I protein binding Source: ParkinsonsUK-UCL
  • polyubiquitin binding Source: BHF-UCL
  • protein domain specific binding Source: MGI
  • protein phosphatase binding Source: MGI
  • RNA binding Source: MGI
  • ubiquitin-like protein ligase binding Source: MGI
  • ubiquitin protein ligase binding Source: MGI
  • ubiquitin-specific protease binding Source: ParkinsonsUK-UCL

GO - Biological processi

Keywordsi

Molecular functionHydrolase
Biological processAutophagy, DNA damage, DNA repair, Transport, Ubl conjugation pathway
LigandATP-binding, Lipid-binding, Nucleotide-binding

Enzyme and pathway databases

ReactomeiR-MMU-110320. Translesion Synthesis by POLH.
R-MMU-3371511. HSF1 activation.
R-MMU-382556. ABC-family proteins mediated transport.
R-MMU-532668. N-glycan trimming in the ER and Calnexin/Calreticulin cycle.
R-MMU-5358346. Hedgehog ligand biogenesis.
R-MMU-5689877. Josephin domain DUBs.
R-MMU-5689896. Ovarian tumor domain proteases.
R-MMU-6798695. Neutrophil degranulation.
R-MMU-8876725. Protein methylation.

Names & Taxonomyi

Protein namesi
Recommended name:
Transitional endoplasmic reticulum ATPase (EC:3.6.4.6By similarity)
Short name:
TER ATPase
Alternative name(s):
15S Mg(2+)-ATPase p97 subunit
Valosin-containing protein
Short name:
VCP
Gene namesi
Name:Vcp
OrganismiMus musculus (Mouse)
Taxonomic identifieri10090 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaMyomorphaMuroideaMuridaeMurinaeMusMus
Proteomesi
  • UP000000589 Componenti: Chromosome 4

Organism-specific databases

MGIiMGI:99919. Vcp.

Subcellular locationi

  • Cytoplasmcytosol
  • Nucleus
  • Endoplasmic reticulum By similarity

  • Note: Recruited to the cytoplasmic surface of the endoplasmic reticulum via interaction with AMFR/gp78. Following DNA double-strand breaks, recruited to the sites of damage. Recruited to stalled replication forks via interaction with SPRTN (By similarity).By similarity

GO - Cellular componenti

  • ATPase complex Source: CAFA
  • cytosol Source: UniProtKB
  • Derlin-1 retrotranslocation complex Source: ParkinsonsUK-UCL
  • endoplasmic reticulum Source: UniProtKB
  • endoplasmic reticulum membrane Source: ParkinsonsUK-UCL
  • extracellular exosome Source: MGI
  • lipid particle Source: MGI
  • myelin sheath Source: UniProtKB
  • nucleoplasm Source: MGI
  • nucleus Source: MGI
  • perinuclear region of cytoplasm Source: MGI
  • proteasome complex Source: MGI
  • protein complex Source: MGI
  • site of double-strand break Source: UniProtKB
  • VCP-NPL4-UFD1 AAA ATPase complex Source: ParkinsonsUK-UCL
  • VCP-NSFL1C complex Source: ParkinsonsUK-UCL

Keywords - Cellular componenti

Cytoplasm, Endoplasmic reticulum, Nucleus

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi144R → A: Loss of phospholipid-binding. 1 Publication1

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Initiator methionineiRemovedBy similarity
ChainiPRO_00000845732 – 806Transitional endoplasmic reticulum ATPaseAdd BLAST805

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei2N-acetylalanineBy similarity1
Modified residuei3PhosphoserineBy similarity1
Modified residuei7PhosphoserineBy similarity1
Modified residuei13PhosphoserineBy similarity1
Modified residuei37PhosphoserineBy similarity1
Modified residuei315N6,N6,N6-trimethyllysine; by VCPKMT1 Publication1
Modified residuei436PhosphothreonineBy similarity1
Modified residuei462PhosphoserineBy similarity1
Modified residuei502N6-acetyllysineCombined sources1
Modified residuei505N6-acetyllysineCombined sources1
Modified residuei668N6-acetyllysine; alternateCombined sources1
Modified residuei668N6-succinyllysine; alternateCombined sources1
Modified residuei702PhosphoserineBy similarity1
Modified residuei754N6-acetyllysineCombined sources1
Modified residuei770PhosphoserineCombined sources1
Modified residuei775PhosphoserineBy similarity1
Modified residuei787PhosphoserineBy similarity1
Modified residuei805PhosphotyrosineCombined sources1

Post-translational modificationi

Phosphorylated by tyrosine kinases in response to T-cell antigen receptor activation. Phosphorylated in mitotic cells.By similarity
ISGylated.1 Publication
Methylation at Lys-315 catalyzed by VCPKMT is increased in the presence of ASPSCR1. Lys-315 methylation may decrease ATPase activity (By similarity).By similarity

Keywords - PTMi

Acetylation, Methylation, Phosphoprotein, Ubl conjugation

Proteomic databases

EPDiQ01853.
MaxQBiQ01853.
PaxDbiQ01853.
PeptideAtlasiQ01853.
PRIDEiQ01853.

2D gel databases

REPRODUCTION-2DPAGEiQ01853.
UCD-2DPAGEiQ01853.

PTM databases

iPTMnetiQ01853.
PhosphoSitePlusiQ01853.
SwissPalmiQ01853.

Expressioni

Gene expression databases

BgeeiENSMUSG00000028452.
CleanExiMM_VCP.
GenevisibleiQ01853. MM.

Interactioni

Subunit structurei

Homohexamer. Forms a ring-shaped particle of 12.5 nm diameter, that displays 6-fold radial symmetry. Part of a ternary complex containing STX5A, NSFL1C and VCP. NSFL1C forms a homotrimer that binds to one end of a VCP homohexamer. The complex binds to membranes enriched in phosphatidylethanolamine-containing lipids and promotes Golgi membrane fusion. Binds to a heterodimer of NPLOC4 and UFD1, binding to this heterodimer inhibits Golgi-membrane fusion. Interaction with VCIP135 leads to dissociation of the complex via ATP hydrolysis by VCP. Part of a ternary complex containing NPLOC4, UFD1 and VCP. Interacts with NSFL1C-like protein p37; the complex has membrane fusion activity and is required for Golgi and endoplasmic reticulum biogenesis. Interacts with RNF103. Interacts with TRIM13 and TRIM21. Component of a VCP/p97-AMFR/gp78 complex that participates in the final step of the endoplasmic reticulum-associated degradation (ERAD) of HMGCR. Interacts directly with AMFR/gp78 (via its VIM). Interacts with RHBDD1 (via C-terminal domain). Interacts with SPRTN; leading to recruitment to stalled replication forks. Interacts with SELENOS and SYVN1, as well as with DERL1, DERL2 and DERL3; which probably transfer misfolded proteins from the ER to VCP. Interacts with SVIP. Component of a complex required to couple retrotranslocation, ubiquitination and deglycosylation composed of NGLY1, SAKS1, AMFR, VCP and RAD23B. Directly interacts with UBXN4 and RNF19A. Interacts with CASR. Interacts with UBXN6, UBE4B and YOD1. Interacts with clathrin. Interacts with RNF103. Interacts with TRIM13 and TRIM21. Component of a VCP/p97-AMFR/gp78 complex that participates in the final step of the endoplasmic reticulum-associated degradation (ERAD) of HMGCR. Interacts directly with AMFR/gp78 (via its VIM). Interacts with WASHC5. Interacts with UBOX5. Interacts (via N- terminus) with UBXN7, UBXN8, and probably several other UBX domain-containing proteins (via UBX domains); the interactions are mutually exclusive with VIM-dependent interactions such as those with AMFR and SELENOS. Forms a complex with UBQLN1 and UBXN4 (By similarity). Interacts (via the PIM motif) with RNF31 (via the PUB domain) (By similarity). Interacts with DDX58/RIG-I and RNF125; interaction takes place when DDX58/RIG-I is ubiquitinated via'Lys-63'-linked ubiquitin on its CARD domains, leading to recruit RNF125 and promote ubiquitination and degradation of DDX58/RIG-I (By similarity). Interacts with BAG6 (By similarity). Interacts with UBXN10 (By similarity).By similarity5 Publications

Binary interactionsi

Show more details

GO - Molecular functioni

  • BAT3 complex binding Source: MGI
  • identical protein binding Source: CAFA
  • K48-linked polyubiquitin binding Source: ParkinsonsUK-UCL
  • MHC class I protein binding Source: ParkinsonsUK-UCL
  • polyubiquitin binding Source: BHF-UCL
  • protein domain specific binding Source: MGI
  • protein phosphatase binding Source: MGI
  • ubiquitin-like protein ligase binding Source: MGI
  • ubiquitin protein ligase binding Source: MGI
  • ubiquitin-specific protease binding Source: ParkinsonsUK-UCL

Protein-protein interaction databases

BioGridi234661. 52 interactors.
DIPiDIP-29796N.
IntActiQ01853. 36 interactors.
MINTiMINT-220770.
STRINGi10090.ENSMUSP00000030164.

Chemistry databases

BindingDBiQ01853.

Structurei

Secondary structure

1806
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi25 – 29Combined sources5
Beta strandi38 – 41Combined sources4
Helixi43 – 48Combined sources6
Beta strandi56 – 60Combined sources5
Helixi62 – 64Combined sources3
Beta strandi66 – 73Combined sources8
Beta strandi75 – 77Combined sources3
Beta strandi79 – 83Combined sources5
Helixi86 – 91Combined sources6
Beta strandi99 – 104Combined sources6
Beta strandi106 – 110Combined sources5
Beta strandi114 – 119Combined sources6
Helixi120 – 122Combined sources3
Turni123 – 125Combined sources3
Helixi130 – 133Combined sources4
Helixi135 – 139Combined sources5
Turni140 – 142Combined sources3
Beta strandi144 – 147Combined sources4
Beta strandi151 – 156Combined sources6
Beta strandi159 – 176Combined sources18
Beta strandi181 – 183Combined sources3
Beta strandi193 – 195Combined sources3
Beta strandi198 – 200Combined sources3
Helixi203 – 205Combined sources3
Helixi211 – 225Combined sources15
Helixi227 – 232Combined sources6
Beta strandi240 – 244Combined sources5
Helixi251 – 261Combined sources11
Beta strandi265 – 269Combined sources5
Helixi271 – 274Combined sources4
Helixi281 – 295Combined sources15
Beta strandi298 – 305Combined sources8
Helixi306 – 308Combined sources3
Helixi312 – 315Combined sources4
Helixi321 – 333Combined sources13
Helixi337 – 339Combined sources3
Beta strandi341 – 348Combined sources8
Helixi350 – 352Combined sources3
Helixi355 – 357Combined sources3
Beta strandi365 – 368Combined sources4
Helixi374 – 383Combined sources10
Turni384 – 387Combined sources4
Beta strandi388 – 390Combined sources3
Helixi396 – 402Combined sources7
Helixi408 – 430Combined sources23
Helixi439 – 444Combined sources6
Helixi449 – 456Combined sources8
Beta strandi457 – 460Combined sources4
Helixi476 – 478Combined sources3
Helixi483 – 498Combined sources16
Helixi500 – 506Combined sources7
Beta strandi512 – 517Combined sources6
Beta strandi519 – 523Combined sources5
Helixi524 – 534Combined sources11
Beta strandi538 – 542Combined sources5
Helixi544 – 552Combined sources9
Helixi558 – 568Combined sources11
Beta strandi571 – 576Combined sources6
Helixi581 – 585Combined sources5
Turni586 – 590Combined sources5
Helixi599 – 609Combined sources11
Beta strandi615 – 624Combined sources10
Helixi626 – 628Combined sources3
Helixi631 – 634Combined sources4
Turni636 – 638Combined sources3
Beta strandi641 – 644Combined sources4
Helixi650 – 661Combined sources12
Helixi672 – 677Combined sources6
Helixi684 – 706Combined sources23
Helixi733 – 740Combined sources8
Helixi749 – 762Combined sources14

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
1E32X-ray2.90A1-458[»]
1R7RX-ray3.60A1-806[»]
1S3SX-ray2.90A/B/C/D/E/F1-458[»]
2PJHNMR-B21-213[»]
3CF0X-ray3.00A/B/C/D/E/F/G/H/I/J/K/L/M/N463-763[»]
3CF1X-ray4.40A/B/C1-806[»]
3CF2X-ray3.50A/B/C/D1-806[»]
3CF3X-ray4.25A/B/C1-806[»]
DisProtiDP00435.
ProteinModelPortaliQ01853.
SMRiQ01853.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ01853.

Family & Domainsi

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni797 – 806Interaction with UBXN6By similarity10

Motif

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Motifi802 – 806PIM motifBy similarity5

Domaini

The N-terminal domain shows evolutionary conservation with that of PEX1, and is able to bind phospholipids with a preference for phosphatidylinositol mono- and bisphosphates.
The PIM (PUB-interaction motif) motif mediates interaction with the PUB domain of RNF31.By similarity

Sequence similaritiesi

Belongs to the AAA ATPase family.Curated

Phylogenomic databases

eggNOGiKOG0730. Eukaryota.
COG0464. LUCA.
GeneTreeiENSGT00880000138021.
HOVERGENiHBG001226.
InParanoidiQ01853.
KOiK13525.
OMAiPIDDTTE.
OrthoDBiEOG091G024K.
PhylomeDBiQ01853.
TreeFamiTF300542.

Family and domain databases

Gene3Di3.10.330.10. 1 hit.
InterProiView protein in InterPro
IPR003593. AAA+_ATPase.
IPR005938. AAA_ATPase_CDC48.
IPR009010. Asp_de-COase-like_dom.
IPR003959. ATPase_AAA_core.
IPR003960. ATPase_AAA_CS.
IPR004201. Cdc48_dom2.
IPR029067. CDC48_domain_2-like.
IPR003338. CDC4_N-term_subdom.
IPR027417. P-loop_NTPase.
IPR015415. Vps4_C.
PfamiView protein in Pfam
PF00004. AAA. 2 hits.
PF02933. CDC48_2. 1 hit.
PF02359. CDC48_N. 1 hit.
PF09336. Vps4_C. 1 hit.
SMARTiView protein in SMART
SM00382. AAA. 2 hits.
SM01072. CDC48_2. 1 hit.
SM01073. CDC48_N. 1 hit.
SUPFAMiSSF50692. SSF50692. 1 hit.
SSF52540. SSF52540. 2 hits.
SSF54585. SSF54585. 1 hit.
TIGRFAMsiTIGR01243. CDC48. 1 hit.
PROSITEiView protein in PROSITE
PS00674. AAA. 2 hits.

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

Q01853-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MASGADSKGD DLSTAILKQK NRPNRLIVDE AINEDNSVVS LSQPKMDELQ
60 70 80 90 100
LFRGDTVLLK GKKRREAVCI VLSDDTCSDE KIRMNRVVRN NLRVRLGDVI
110 120 130 140 150
SIQPCPDVKY GKRIHVLPID DTVEGITGNL FEVYLKPYFL EAYRPIRKGD
160 170 180 190 200
IFLVRGGMRA VEFKVVETDP SPYCIVAPDT VIHCEGEPIK REDEEESLNE
210 220 230 240 250
VGYDDIGGCR KQLAQIKEMV ELPLRHPALF KAIGVKPPRG ILLYGPPGTG
260 270 280 290 300
KTLIARAVAN ETGAFFFLIN GPEIMSKLAG ESESNLRKAF EEAEKNAPAI
310 320 330 340 350
IFIDELDAIA PKREKTHGEV ERRIVSQLLT LMDGLKQRAH VIVMAATNRP
360 370 380 390 400
NSIDPALRRF GRFDREVDIG IPDATGRLEI LQIHTKNMKL ADDVDLEQVA
410 420 430 440 450
NETHGHVGAD LAALCSEAAL QAIRKKMDLI DLEDETIDAE VMNSLAVTMD
460 470 480 490 500
DFRWALSQSN PSALRETVVE VPQVTWEDIG GLEDVKRELQ ELVQYPVEHP
510 520 530 540 550
DKFLKFGMTP SKGVLFYGPP GCGKTLLAKA IANECQANFI SIKGPELLTM
560 570 580 590 600
WFGESEANVR EIFDKARQAA PCVLFFDELD SIAKARGGNI GDGGGAADRV
610 620 630 640 650
INQILTEMDG MSTKKNVFII GATNRPDIID PAILRPGRLD QLIYIPLPDE
660 670 680 690 700
KSRVAILKAN LRKSPVAKDV DLEFLAKMTN GFSGADLTEI CQRACKLAIR
710 720 730 740 750
ESIESEIRRE RERQTNPSAM EVEEDDPVPE IRRDHFEEAM RFARRSVSDN
760 770 780 790 800
DIRKYEMFAQ TLQQSRGFGS FRFPSGNQGG AGPSQGSGGG TGGSVYTEDN

DDDLYG
Length:806
Mass (Da):89,322
Last modified:May 1, 2007 - v4
Checksum:i501B721D3A77BA8A
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti73S → Y in BAC27119 (PubMed:16141072).Curated1
Sequence conflicti199N → Y in BAE39824 (PubMed:16141072).Curated1
Sequence conflicti206I → V in CAA78412 (PubMed:1382975).Curated1
Sequence conflicti359R → Q in BAC27119 (PubMed:16141072).Curated1
Sequence conflicti439A → T in BAE40919 (PubMed:16141072).Curated1
Sequence conflicti624N → S in BAE34876 (PubMed:16141072).Curated1
Sequence conflicti684G → V in BAC25849 (PubMed:16141072).Curated1

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
Z14044 mRNA. Translation: CAA78412.1.
AK028264 mRNA. Translation: BAC25849.1.
AK030751 mRNA. Translation: BAC27119.1.
AK149931 mRNA. Translation: BAE29175.1.
AK151109 mRNA. Translation: BAE30119.1.
AK151418 mRNA. Translation: BAE30383.1.
AK153249 mRNA. Translation: BAE31840.1.
AK159177 mRNA. Translation: BAE34876.1.
AK159509 mRNA. Translation: BAE35141.1.
AK167794 mRNA. Translation: BAE39824.1.
AK169140 mRNA. Translation: BAE40919.1.
AL672276 Genomic DNA. Translation: CAM14316.1.
BC043053 mRNA. Translation: AAH43053.1.
BC049114 mRNA. Translation: AAH49114.1.
CCDSiCCDS18086.1.
PIRiS25197.
RefSeqiNP_033529.3. NM_009503.4.
UniGeneiMm.245976.
Mm.262053.
Mm.469106.

Genome annotation databases

EnsembliENSMUST00000030164; ENSMUSP00000030164; ENSMUSG00000028452.
GeneIDi269523.
KEGGimmu:269523.
UCSCiuc008sor.2. mouse.

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.

Entry informationi

Entry nameiTERA_MOUSE
AccessioniPrimary (citable) accession number: Q01853
Secondary accession number(s): Q3TFH9
, Q3TIM2, Q3TXN9, Q6PI18, Q8BSR6, Q8CEG4
Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 1, 1993
Last sequence update: May 1, 2007
Last modified: July 5, 2017
This is version 187 of the entry and version 4 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. MGD cross-references
    Mouse Genome Database (MGD) cross-references in UniProtKB/Swiss-Prot
  2. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  3. SIMILARITY comments
    Index of protein domains and families