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Protein

E3 ubiquitin-protein ligase CHIP

Gene

STUB1

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

E3 ubiquitin-protein ligase which targets misfolded chaperone substrates towards proteasomal degradation. Collaborates with ATXN3 in the degradation of misfolded chaperone substrates: ATXN3 restricting the length of ubiquitin chain attached to STUB1/CHIP substrates and preventing further chain extension. Ubiquitinates NOS1 in concert with Hsp70 and Hsp40. Modulates the activity of several chaperone complexes, including Hsp70, Hsc70 and Hsp90. Mediates transfer of non-canonical short ubiquitin chains to HSPA8 that have no effect on HSPA8 degradation. Mediates polyubiquitination of DNA polymerase beta (POLB) at 'Lys-41', 'Lys-61' and 'Lys-81', thereby playing a role in base-excision repair: catalyzes polyubiquitination by amplifying the HUWE1/ARF-BP1-dependent monoubiquitination and leading to POLB-degradation by the proteasome. Mediates polyubiquitination of CYP3A4. Ubiquitinates EPHA2 and may regulate the receptor stability and activity through proteasomal degradation. Acts as a co-chaperone for HSPA1A and HSPA1B chaperone proteins and promotes ubiquitin-mediated protein degradation (PubMed:27708256). Negatively regulates the suppressive function of regulatory T-cells (Treg) during inflammation by mediating the ubiquitination and degradation of FOXP3 in a HSPA1A/B-dependent manner (PubMed:23973223). Negatively regulates TGF-beta signaling by modulating the basal level of SMAD3 via ubiquitin-mediated degradation (PubMed:24613385).10 Publications

Miscellaneous

Antibodies against STUB1 are found in patients with chronic lymphocytic leukemia (CLL) and in colorectal cancer patients.

Catalytic activityi

S-ubiquitinyl-[E2 ubiquitin-conjugating enzyme]-L-cysteine + [acceptor protein]-L-lysine = [E2 ubiquitin-conjugating enzyme]-L-cysteine + N6-ubiquitinyl-[acceptor protein]-L-lysine.2 Publications

Pathwayi: protein ubiquitination

This protein is involved in the pathway protein ubiquitination, which is part of Protein modification.2 Publications
View all proteins of this organism that are known to be involved in the pathway protein ubiquitination and in Protein modification.

GO - Molecular functioni

  • enzyme binding Source: UniProtKB
  • G-protein coupled receptor binding Source: ParkinsonsUK-UCL
  • Hsp70 protein binding Source: HGNC
  • Hsp90 protein binding Source: BHF-UCL
  • kinase binding Source: BHF-UCL
  • misfolded protein binding Source: BHF-UCL
  • protein binding, bridging Source: HGNC
  • protein homodimerization activity Source: ParkinsonsUK-UCL
  • SMAD binding Source: HGNC
  • TPR domain binding Source: HGNC
  • ubiquitin protein ligase activity Source: UniProtKB
  • ubiquitin protein ligase activity involved in ERAD pathway Source: ParkinsonsUK-UCL
  • ubiquitin protein ligase binding Source: ParkinsonsUK-UCL
  • ubiquitin-protein transferase activity Source: UniProtKB
  • ubiquitin-ubiquitin ligase activity Source: UniProtKB

GO - Biological processi

  • cellular response to misfolded protein Source: BHF-UCL
  • DNA repair Source: UniProtKB-KW
  • endoplasmic reticulum unfolded protein response Source: Ensembl
  • ERBB2 signaling pathway Source: Reactome
  • misfolded or incompletely synthesized protein catabolic process Source: BHF-UCL
  • negative regulation of protein binding Source: Ensembl
  • negative regulation of transforming growth factor beta receptor signaling pathway Source: UniProtKB
  • positive regulation of chaperone-mediated protein complex assembly Source: BHF-UCL
  • positive regulation of proteasomal ubiquitin-dependent protein catabolic process Source: HGNC
  • positive regulation of protein ubiquitination Source: HGNC
  • positive regulation of ubiquitin-protein transferase activity Source: Ensembl
  • proteasome-mediated ubiquitin-dependent protein catabolic process Source: UniProtKB
  • protein autoubiquitination Source: UniProtKB
  • protein K63-linked ubiquitination Source: UniProtKB
  • protein maturation Source: HGNC
  • protein polyubiquitination Source: HGNC
  • protein ubiquitination Source: BHF-UCL
  • protein ubiquitination involved in ubiquitin-dependent protein catabolic process Source: ParkinsonsUK-UCL
  • regulation of glucocorticoid metabolic process Source: HGNC
  • regulation of protein stability Source: BHF-UCL
  • ubiquitin-dependent protein catabolic process Source: UniProtKB
  • ubiquitin-dependent SMAD protein catabolic process Source: HGNC

Keywordsi

Molecular functionTransferase
Biological processDNA damage, DNA repair, Ubl conjugation pathway

Enzyme and pathway databases

BRENDAi2.3.2.B10. 2681.
ReactomeiR-HSA-2173788. Downregulation of TGF-beta receptor signaling.
R-HSA-8863795. Downregulation of ERBB2 signaling.
R-HSA-983168. Antigen processing: Ubiquitination & Proteasome degradation.
SignaLinkiQ9UNE7.
SIGNORiQ9UNE7.
UniPathwayiUPA00143.

Names & Taxonomyi

Protein namesi
Recommended name:
E3 ubiquitin-protein ligase CHIPCurated (EC:2.3.2.272 Publications)
Alternative name(s):
Antigen NY-CO-71 Publication
CLL-associated antigen KW-81 Publication
Carboxy terminus of Hsp70-interacting protein1 Publication
RING-type E3 ubiquitin transferase CHIPCurated
STIP1 homology and U box-containing protein 1Imported
Gene namesi
Name:STUB1Imported
Synonyms:CHIP1 Publication
ORF Names:PP1131Imported
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 16

Organism-specific databases

HGNCiHGNC:11427. STUB1.

Subcellular locationi

GO - Cellular componenti

  • cytoplasm Source: HGNC
  • cytosol Source: HPA
  • endoplasmic reticulum Source: ParkinsonsUK-UCL
  • extracellular exosome Source: UniProtKB
  • nuclear inclusion body Source: BHF-UCL
  • nucleoplasm Source: HPA
  • ubiquitin conjugating enzyme complex Source: HGNC
  • ubiquitin ligase complex Source: UniProtKB
  • Z disc Source: Ensembl

Keywords - Cellular componenti

Cytoplasm, Nucleus

Pathology & Biotechi

Involvement in diseasei

Spinocerebellar ataxia, autosomal recessive, 16 (SCAR16)5 Publications
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionSpinocerebellar ataxia defines a clinically and genetically heterogeneous group of cerebellar disorders. Patients show progressive incoordination of gait and often poor coordination of hands, speech and eye movements, due to degeneration of the cerebellum with variable involvement of the brainstem and spinal cord. SCAR16 is characterized by truncal and limb ataxia resulting in gait instability. Additionally, patients may show dysarthria, nystagmus, spasticity of the lower limbs, and mild peripheral sensory neuropathy.
See also OMIM:615768
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_07234828E → K in SCAR16; reduces protein level; does not reduce ubiquitin ligase activity and autoubiquitination. 1 Publication1
Natural variantiVAR_07234965N → S in SCAR16; reduces protein level; reduces ubiquitin ligase activity; does not change autoubiquitination. 1 PublicationCorresponds to variant dbSNP:rs690016544Ensembl.1
Natural variantiVAR_07129379A → D in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777347Ensembl.1
Natural variantiVAR_07129479A → T in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777346Ensembl.1
Natural variantiVAR_071295123L → V in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777344Ensembl.1
Natural variantiVAR_071296130N → I in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777341Ensembl.1
Natural variantiVAR_072350145K → Q in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs146251364Ensembl.1
Natural variantiVAR_071297147W → C in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777342Ensembl.1
Natural variantiVAR_071298165L → F in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777340Ensembl.1
Natural variantiVAR_071299236S → T in SCAR16. 1 Publication1
Natural variantiVAR_071300240M → T in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777345Ensembl.1
Natural variantiVAR_071301246T → M in SCAR16; inhibits ubiquitin ligase activity and autoubiquitination. 2 PublicationsCorresponds to variant dbSNP:rs587777343Ensembl.1

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi30K → A: Loss of interaction with FOXP3 and its ability to ubiquitinate FOXP3. Loss of interaction with SMAD3, HSPA8, HSP90AA1 and HSP90AB1. 2 Publications1
Mutagenesisi260H → Q: Loss of ability to ubiquitinate FOXP3. 1 Publication1
Mutagenesisi269P → A: Abolishes E3 ligase activity. 1 Publication1

Keywords - Diseasei

Disease mutation, Neurodegeneration

Organism-specific databases

DisGeNETi10273.
MalaCardsiSTUB1.
MIMi615768. phenotype.
OpenTargetsiENSG00000103266.
Orphaneti1173. Cerebellar ataxia - hypogonadism.
PharmGKBiPA36227.

Polymorphism and mutation databases

BioMutaiSTUB1.
DMDMi78099173.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
ChainiPRO_00001063291 – 303E3 ubiquitin-protein ligase CHIPAdd BLAST303

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Cross-linki2Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)1 Publication
Modified residuei19PhosphoserineCombined sources1 Publication1
Cross-linki22Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)1 Publication
Modified residuei23PhosphoserineCombined sources1
Modified residuei25PhosphoserineCombined sources1
Modified residuei149PhosphoserineCombined sources1
Cross-linki221Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)1 Publication
Cross-linki255Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)1 Publication
Modified residuei273PhosphoserineCombined sources1

Post-translational modificationi

Monoubiquitinated at Lys-2 following cell stress by UBE2W, promoting the interaction with ATXN3 (By similarity). Auto-ubiquitinated; mediated by UBE2D1 and UBE2D2.By similarity2 Publications

Keywords - PTMi

Isopeptide bond, Phosphoprotein, Ubl conjugation

Proteomic databases

EPDiQ9UNE7.
PaxDbiQ9UNE7.
PeptideAtlasiQ9UNE7.
PRIDEiQ9UNE7.

PTM databases

iPTMnetiQ9UNE7.
PhosphoSitePlusiQ9UNE7.

Expressioni

Tissue specificityi

Highly expressed in skeletal muscle, heart, pancreas, brain and placenta. Detected in kidney, liver and lung.2 Publications

Inductioni

Up-regulated by inflammatory signals in regulatory T-cells (Treg).1 Publication

Gene expression databases

BgeeiENSG00000103266.
CleanExiHS_STUB1.
ExpressionAtlasiQ9UNE7. baseline and differential.
GenevisibleiQ9UNE7. HS.

Organism-specific databases

HPAiCAB037202.
CAB037209.
HPA041222.
HPA043531.

Interactioni

Subunit structurei

Homodimer (By similarity). Interacts with BAG2 (PubMed:16169850). Interacts with E2 ubiquitin conjugating enzymes UBE2D1, UBE2D2 and UBE2D3 (PubMed:11557750). Detected in a ternary complex containing STUB1, HSPA1A and HSPBP1 (PubMed:15215316). Interacts with MKKS (PubMed:18094050). Interacts with DNAAF4 (PubMed:19423554). Interacts with POLB (PubMed:19713937). Interacts (when monoubiquitinated) with ATXN3. Interacts with UBE2W. Interacts (via the U-box domain) with the UBE2V2-UBE2N heterodimer; the complex has a specific 'Lys-63'-linked polyubiquitination activity (By similarity). Interacts with DNAJB6 (PubMed:22366786). Interacts with FOXP3 (PubMed:23973223). Interacts with FLCN (PubMed:27353360). Interacts with HSP90AA1 (PubMed:27353360, PubMed:24613385). Interacts with HSP90 (PubMed:11146632). Interacts with UBE2N and UBE2V1 (PubMed:16307917). Interacts (via TPR repeats) with the C-terminal domain of HSPA1A (PubMed:10330192). Interacts with the non-acetylated form of HSPA1A and HSPA1B (PubMed:27708256). Interacts (via TPR repeats) with the C-terminal domain of HSPA8 (PubMed:10330192, PubMed:11557750, PubMed:23990462, PubMed:27708256). Interacts with SMAD3 and HSP90AB1 (PubMed:24613385).By similarity15 Publications

Binary interactionsi

Show more details

GO - Molecular functioni

  • enzyme binding Source: UniProtKB
  • G-protein coupled receptor binding Source: ParkinsonsUK-UCL
  • Hsp70 protein binding Source: HGNC
  • Hsp90 protein binding Source: BHF-UCL
  • kinase binding Source: BHF-UCL
  • misfolded protein binding Source: BHF-UCL
  • protein binding, bridging Source: HGNC
  • protein homodimerization activity Source: ParkinsonsUK-UCL
  • SMAD binding Source: HGNC
  • TPR domain binding Source: HGNC
  • ubiquitin protein ligase binding Source: ParkinsonsUK-UCL

Protein-protein interaction databases

BioGridi115563. 268 interactors.
DIPiDIP-29752N.
IntActiQ9UNE7. 143 interactors.
MINTiMINT-1132706.
STRINGi9606.ENSP00000219548.

Structurei

Secondary structure

1303
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Helixi26 – 38Combined sources13
Helixi42 – 55Combined sources14
Helixi60 – 72Combined sources13
Helixi76 – 89Combined sources14
Helixi94 – 106Combined sources13
Helixi110 – 126Combined sources17
Helixi134 – 147Combined sources14
Turni148 – 151Combined sources4

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
4KBQX-ray2.91A/B21-154[»]
ProteinModelPortaliQ9UNE7.
SMRiQ9UNE7.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Repeati26 – 59TPR 1Add BLAST34
Repeati60 – 93TPR 2Add BLAST34
Repeati95 – 127TPR 3Add BLAST33
Domaini226 – 300U-boxAdd BLAST75

Domaini

The U-box domain is required for the ubiquitin protein ligase activity.By similarity
The TPR domain is essential for ubiquitination mediated by UBE2D1.1 Publication

Keywords - Domaini

Repeat, TPR repeat

Phylogenomic databases

eggNOGiKOG4642. Eukaryota.
ENOG410ZC2R. LUCA.
GeneTreeiENSGT00730000111218.
HOGENOMiHOG000163725.
HOVERGENiHBG053046.
InParanoidiQ9UNE7.
KOiK09561.
OMAiTNATYFT.
OrthoDBiEOG091G0FJB.
PhylomeDBiQ9UNE7.
TreeFamiTF313937.

Family and domain databases

Gene3Di1.25.40.10. 2 hits.
3.30.40.10. 1 hit.
InterProiView protein in InterPro
IPR013026. TPR-contain_dom.
IPR011990. TPR-like_helical_dom.
IPR019734. TPR_repeat.
IPR003613. Ubox_domain.
IPR013083. Znf_RING/FYVE/PHD.
PfamiView protein in Pfam
PF04564. U-box. 1 hit.
SMARTiView protein in SMART
SM00028. TPR. 3 hits.
SM00504. Ubox. 1 hit.
SUPFAMiSSF48452. SSF48452. 1 hit.
PROSITEiView protein in PROSITE
PS50005. TPR. 3 hits.
PS50293. TPR_REGION. 1 hit.
PS51698. U_BOX. 1 hit.

Sequences (2)i

Sequence statusi: Complete.

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q9UNE7-1) [UniParc]FASTAAdd to basket

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

« Hide

        10         20         30         40         50
MKGKEEKEGG ARLGAGGGSP EKSPSAQELK EQGNRLFVGR KYPEAAACYG
60 70 80 90 100
RAITRNPLVA VYYTNRALCY LKMQQHEQAL ADCRRALELD GQSVKAHFFL
110 120 130 140 150
GQCQLEMESY DEAIANLQRA YSLAKEQRLN FGDDIPSALR IAKKKRWNSI
160 170 180 190 200
EERRIHQESE LHSYLSRLIA AERERELEEC QRNHEGDEDD SHVRAQQACI
210 220 230 240 250
EAKHDKYMAD MDELFSQVDE KRKKRDIPDY LCGKISFELM REPCITPSGI
260 270 280 290 300
TYDRKDIEEH LQRVGHFDPV TRSPLTQEQL IPNLAMKEVI DAFISENGWV

EDY
Length:303
Mass (Da):34,856
Last modified:October 25, 2005 - v2
Checksum:i7E7D6568B17070BF
GO
Isoform 2 (identifier: Q9UNE7-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-72: Missing.

Note: No experimental confirmation available.
Show »
Length:231
Mass (Da):27,067
Checksum:iBA7782D3C2F9E1F9
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti52A → V in AAD33400 (PubMed:10330192).Curated1
Sequence conflicti272R → G in AAC18038 (PubMed:9610721).Curated1
Sequence conflicti280L → F in AAC18038 (PubMed:9610721).Curated1

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_07234828E → K in SCAR16; reduces protein level; does not reduce ubiquitin ligase activity and autoubiquitination. 1 Publication1
Natural variantiVAR_07234965N → S in SCAR16; reduces protein level; reduces ubiquitin ligase activity; does not change autoubiquitination. 1 PublicationCorresponds to variant dbSNP:rs690016544Ensembl.1
Natural variantiVAR_07129379A → D in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777347Ensembl.1
Natural variantiVAR_07129479A → T in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777346Ensembl.1
Natural variantiVAR_071295123L → V in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777344Ensembl.1
Natural variantiVAR_071296130N → I in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777341Ensembl.1
Natural variantiVAR_072350145K → Q in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs146251364Ensembl.1
Natural variantiVAR_071297147W → C in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777342Ensembl.1
Natural variantiVAR_071298165L → F in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777340Ensembl.1
Natural variantiVAR_071299236S → T in SCAR16. 1 Publication1
Natural variantiVAR_071300240M → T in SCAR16. 1 PublicationCorresponds to variant dbSNP:rs587777345Ensembl.1
Natural variantiVAR_071301246T → M in SCAR16; inhibits ubiquitin ligase activity and autoubiquitination. 2 PublicationsCorresponds to variant dbSNP:rs587777343Ensembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0159471 – 72Missing in isoform 2. 1 PublicationAdd BLAST72

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF039689 mRNA. Translation: AAC18038.1.
AF129085 mRNA. Translation: AAD33400.1.
AF432221 mRNA. Translation: AAL99927.1.
AF217968 mRNA. Translation: AAG17211.1.
AE006464 Genomic DNA. Translation: AAK61242.1.
Z92544 Genomic DNA. No translation available.
CH471112 Genomic DNA. Translation: EAW85758.1.
BC007545 mRNA. Translation: AAH07545.1.
BC017178 mRNA. Translation: AAH17178.1.
BC022788 mRNA. Translation: AAH22788.1.
BC063617 mRNA. Translation: AAH63617.1.
CCDSiCCDS10419.1. [Q9UNE7-1]
CCDS76797.1. [Q9UNE7-2]
RefSeqiNP_001280126.1. NM_001293197.1. [Q9UNE7-2]
NP_005852.2. NM_005861.3. [Q9UNE7-1]
UniGeneiHs.592081.

Genome annotation databases

EnsembliENST00000219548; ENSP00000219548; ENSG00000103266. [Q9UNE7-1]
ENST00000564370; ENSP00000456875; ENSG00000103266. [Q9UNE7-2]
ENST00000565677; ENSP00000457228; ENSG00000103266. [Q9UNE7-2]
GeneIDi10273.
KEGGihsa:10273.
UCSCiuc002cit.4. human. [Q9UNE7-1]

Keywords - Coding sequence diversityi

Alternative splicing

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 nameiCHIP_HUMAN
AccessioniPrimary (citable) accession number: Q9UNE7
Secondary accession number(s): A2IDB9
, O60526, Q969U2, Q9HBT1
Entry historyiIntegrated into UniProtKB/Swiss-Prot: October 25, 2005
Last sequence update: October 25, 2005
Last modified: July 5, 2017
This is version 162 of the entry and version 2 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Miscellaneousi

Keywords - Technical termi

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

Documents

  1. Human chromosome 16
    Human chromosome 16: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  6. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references