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Protein

Sigma non-opioid intracellular receptor 1

Gene

SIGMAR1

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

Functioni

Functions in lipid transport from the endoplasmic reticulum and is involved in a wide array of cellular functions probably through regulation of the biogenesis of lipid microdomains at the plasma membrane. Involved in the regulation of different receptors it plays a role in BDNF signaling and EGF signaling. Also regulates ion channels like the potassium channel and could modulate neurotransmitter release. Plays a role in calcium signaling through modulation together with ANK2 of the ITP3R-dependent calcium efflux at the endoplasmic reticulum. Plays a role in several other cell functions including proliferation, survival and death. Originally identified for its ability to bind various psychoactive drugs it is involved in learning processes, memory and mood alteration (PubMed:16472803, PubMed:9341151). Necessary for proper mitochondrial axonal transport in motor neurons, in particular the retrograde movement of mitochondria (By similarity).By similarity2 Publications

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sitei126 – 1261Important for ligand binding1 Publication
Sitei172 – 1721Important for ligand binding1 Publication

GO - Molecular functioni

  • drug binding Source: ProtInc
  • opioid receptor activity Source: Ensembl

GO - Biological processi

  • lipid transport Source: UniProtKB-KW
  • nervous system development Source: Ensembl
  • protein homotrimerization Source: UniProtKB
  • regulation of neuron apoptotic process Source: UniProtKB
Complete GO annotation...

Keywords - Molecular functioni

Receptor

Keywords - Biological processi

Lipid transport, Transport

Protein family/group databases

TCDBi8.A.63.1.1. the sigma non-opioid intracellular recpetor, (sigma-1) family.

Names & Taxonomyi

Protein namesi
Recommended name:
Sigma non-opioid intracellular receptor 1
Alternative name(s):
Aging-associated gene 8 protein
SR31747-binding protein
Short name:
SR-BP
Sigma 1-type opioid receptor
Short name:
SIG-1R
Short name:
Sigma1-receptor
Short name:
Sigma1R
Short name:
hSigmaR1
Gene namesi
Name:SIGMAR1
Synonyms:OPRS1, SRBP
ORF Names:AAG8
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 9

Organism-specific databases

HGNCiHGNC:8157. SIGMAR1.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini1 – 99Lumenal1 Publication
Transmembranei10 – 3021Helical1 PublicationAdd
BLAST
Topological domaini31 – 223193Cytoplasmic1 PublicationAdd
BLAST

GO - Cellular componenti

  • cell junction Source: UniProtKB-SubCell
  • endoplasmic reticulum Source: UniProtKB
  • endoplasmic reticulum membrane Source: UniProtKB-SubCell
  • growth cone Source: UniProtKB-SubCell
  • integral component of membrane Source: UniProtKB
  • integral component of plasma membrane Source: ProtInc
  • lipid particle Source: UniProtKB-SubCell
  • nuclear envelope Source: UniProtKB
  • nuclear inner membrane Source: UniProtKB-SubCell
  • nuclear outer membrane Source: UniProtKB-SubCell
  • postsynaptic density Source: UniProtKB
  • postsynaptic membrane Source: UniProtKB-KW
Complete GO annotation...

Keywords - Cellular componenti

Cell junction, Cell membrane, Cell projection, Cytoplasmic vesicle, Endoplasmic reticulum, Lipid droplet, Membrane, Nucleus, Postsynaptic cell membrane, Synapse

Pathology & Biotechi

Involvement in diseasei

Amyotrophic lateral sclerosis 16, juvenile (ALS16)1 Publication
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA neurodegenerative disorder affecting upper motor neurons in the brain and lower motor neurons in the brain stem and spinal cord, resulting in fatal paralysis. Sensory abnormalities are absent. The pathologic hallmarks of the disease include pallor of the corticospinal tract due to loss of motor neurons, presence of ubiquitin-positive inclusions within surviving motor neurons, and deposition of pathologic aggregates. The etiology of amyotrophic lateral sclerosis is likely to be multifactorial, involving both genetic and environmental factors. The disease is inherited in 5-10% of the cases.
See also OMIM:614373
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti102 – 1021E → Q in ALS16; the mutation decreases the viability of motor neurons; the mutant protein is shifted to lower density membranes and forms detergent-resistant complexes; there is an almost 2-fold increase in apoptosis in response to stress compared to controls. 1 Publication
Corresponds to variant rs387906829 [ dbSNP | Ensembl ].
VAR_067311
Distal spinal muscular atrophy, autosomal recessive, 2 (DSMA2)1 Publication
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionAn autosomal recessive neuromuscular disorder characterized by onset of distal muscle weakness and wasting affecting the lower and upper limbs in the first decade. There is no sensory involvement.
See also OMIM:605726

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi123 – 1231E → G: No effect on ligand-binding. 1 Publication
Mutagenesisi126 – 1261D → G: Reduces ligand-binding. No effect on subcellular localization. 1 Publication
Mutagenesisi138 – 1381E → G: No effect on ligand-binding. 1 Publication
Mutagenesisi144 – 1441E → G: No effect on ligand-binding. 1 Publication
Mutagenesisi150 – 1501E → G: No effect on ligand-binding. 1 Publication
Mutagenesisi158 – 1581E → G: No effect on ligand-binding. 1 Publication
Mutagenesisi163 – 1631E → G: No effect on ligand-binding. 1 Publication
Mutagenesisi172 – 1721E → G: Reduces ligand-binding. No effect on subcellular localization. 1 Publication
Mutagenesisi188 – 1881D → G: No effect on ligand-binding. 1 Publication
Mutagenesisi195 – 1951D → G: No effect on ligand-binding. 1 Publication
Mutagenesisi213 – 2131E → G: No effect on ligand-binding. 1 Publication

Keywords - Diseasei

Amyotrophic lateral sclerosis, Disease mutation, Neurodegeneration

Organism-specific databases

MalaCardsiSIGMAR1.
MIMi605726. phenotype.
614373. phenotype.
Orphaneti300605. Juvenile amyotrophic lateral sclerosis.
PharmGKBiPA164725706.

Chemistry

ChEMBLiCHEMBL287.
DrugBankiDB00321. Amitriptyline.
DB09014. Captodiame.
DB00514. Dextromethorphan.
DB00540. Nortriptyline.
DB00652. Pentazocine.
DB00409. Remoxipride.
GuidetoPHARMACOLOGYi2552.

Polymorphism and mutation databases

DMDMi74752153.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 223223Sigma non-opioid intracellular receptor 1PRO_0000268652Add
BLAST

Proteomic databases

EPDiQ99720.
MaxQBiQ99720.
PaxDbiQ99720.
PeptideAtlasiQ99720.
PRIDEiQ99720.
TopDownProteomicsiQ99720-1. [Q99720-1]
Q99720-2. [Q99720-2]
Q99720-3. [Q99720-3]
Q99720-4. [Q99720-4]
Q99720-5. [Q99720-5]

PTM databases

iPTMnetiQ99720.
PhosphoSiteiQ99720.

Expressioni

Tissue specificityi

Widely expressed with higher expression in liver, colon, prostate, placenta, small intestine, heart and pancreas. Expressed in the retina by retinal pigment epithelial cells. Expressed in alpha-motor neurons (PubMed:23314020).4 Publications

Gene expression databases

BgeeiENSG00000147955.
ExpressionAtlasiQ99720. baseline and differential.
GenevisibleiQ99720. HS.

Organism-specific databases

HPAiCAB013470.
HPA018002.
HPA024071.

Interactioni

Subunit structurei

Homotrimer (PubMed:27042935). Forms a ternary complex with ANK2 and ITPR3. The complex is disrupted by agonists. Interacts with KCNA4 (By similarity). Interacts with KCNA2; cocaine consumption leads to increased interaction (By similarity).By similarity1 Publication

Protein-protein interaction databases

BioGridi115569. 12 interactions.
IntActiQ99720. 3 interactions.
STRINGi9606.ENSP00000277010.

Chemistry

BindingDBiQ99720.

Structurei

Secondary structure

1
223
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi9 – 3123Combined sources
Helixi39 – 4911Combined sources
Helixi54 – 6815Combined sources
Helixi76 – 783Combined sources
Beta strandi82 – 865Combined sources
Beta strandi89 – 9810Combined sources
Beta strandi100 – 11112Combined sources
Beta strandi113 – 1164Combined sources
Beta strandi121 – 13111Combined sources
Beta strandi133 – 1375Combined sources
Beta strandi144 – 1463Combined sources
Beta strandi151 – 1544Combined sources
Beta strandi160 – 1645Combined sources
Beta strandi166 – 17611Combined sources
Helixi178 – 1803Combined sources
Helixi182 – 1854Combined sources
Helixi187 – 1915Combined sources
Helixi196 – 21823Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
5HK1X-ray2.51A/B/C1-223[»]
5HK2X-ray3.20A/B/C1-223[»]
ProteinModelPortaliQ99720.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni2 – 87Targeting to endoplasmic reticulum-associated lipid dropletsBy similarity
Regioni99 – 1068Important for ligand-bindingBy similarity
Regioni177 – 22347C-terminal hydrophobic region1 PublicationAdd
BLAST

Domaini

The C-terminal helices form a flat, hydrophobic surface that is probably tightly associated with the cytosolic surface of the endoplasmic reticulum membrane.1 Publication

Sequence similaritiesi

Belongs to the ERG2 family.Curated

Keywords - Domaini

Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiKOG4143. Eukaryota.
ENOG410XP0Z. LUCA.
GeneTreeiENSGT00390000012082.
HOVERGENiHBG058220.
InParanoidiQ99720.
OMAiLFYTLRA.
OrthoDBiEOG091G0KD7.
PhylomeDBiQ99720.
TreeFamiTF300106.

Family and domain databases

InterProiIPR006716. ERG2_sigma1_rcpt-like.
[Graphical view]
PfamiPF04622. ERG2_Sigma1R. 1 hit.
[Graphical view]

Sequences (5)i

Sequence statusi: Complete.

This entry describes 5 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q99720-1) [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
MQWAVGRRWA WAALLLAVAA VLTQVVWLWL GTQSFVFQRE EIAQLARQYA
60 70 80 90 100
GLDHELAFSR LIVELRRLHP GHVLPDEELQ WVFVNAGGWM GAMCLLHASL
110 120 130 140 150
SEYVLLFGTA LGSRGHSGRY WAEISDTIIS GTFHQWREGT TKSEVFYPGE
160 170 180 190 200
TVVHGPGEAT AVEWGPNTWM VEYGRGVIPS TLAFALADTV FSTQDFLTLF
210 220
YTLRSYARGL RLELTTYLFG QDP
Length:223
Mass (Da):25,128
Last modified:May 1, 1997 - v1
Checksum:i0C498636BEB1C443
GO
Isoform 2 (identifier: Q99720-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     31-50: Missing.

Show »
Length:203
Mass (Da):22,803
Checksum:i755BFC0F9182D947
GO
Isoform 3 (identifier: Q99720-3) [UniParc]FASTAAdd to basket
Also known as: Sigma-R1A

The sequence of this isoform differs from the canonical sequence as follows:
     118-148: Missing.

Show »
Length:192
Mass (Da):21,483
Checksum:i9E0C6A120A89126F
GO
Isoform 4 (identifier: Q99720-4) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     103-106: YVLL → ALLG
     107-223: Missing.

Show »
Length:106
Mass (Da):11,992
Checksum:i8A4FDBFAFF6DAEEE
GO
Isoform 5 (identifier: Q99720-5) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     31-52: Missing.
     63-76: Missing.

Note: No experimental confirmation available.
Show »
Length:187
Mass (Da):21,013
Checksum:iE50731B80FB98FBF
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti151 – 1511T → A in AAF64280 (Ref. 4) Curated
Sequence conflicti168 – 1681T → A in ABG29111 (Ref. 6) Curated
Sequence conflicti208 – 2081R → W in AAV33304 (Ref. 5) Curated
Sequence conflicti218 – 2181L → I in ABG29111 (Ref. 6) Curated
Sequence conflicti219 – 2191F → S in BAD96619 (Ref. 9) Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti2 – 21Q → P.1 Publication
Corresponds to variant rs1800866 [ dbSNP | Ensembl ].
VAR_029750
Natural varianti102 – 1021E → Q in ALS16; the mutation decreases the viability of motor neurons; the mutant protein is shifted to lower density membranes and forms detergent-resistant complexes; there is an almost 2-fold increase in apoptosis in response to stress compared to controls. 1 Publication
Corresponds to variant rs387906829 [ dbSNP | Ensembl ].
VAR_067311
Natural varianti211 – 2111R → Q.1 Publication
Corresponds to variant rs192644838 [ dbSNP | Ensembl ].
VAR_029751

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei31 – 5222Missing in isoform 5. 1 PublicationVSP_021981Add
BLAST
Alternative sequencei31 – 5020Missing in isoform 2. 1 PublicationVSP_021982Add
BLAST
Alternative sequencei63 – 7614Missing in isoform 5. 1 PublicationVSP_021983Add
BLAST
Alternative sequencei103 – 1064YVLL → ALLG in isoform 4. 2 PublicationsVSP_021984
Alternative sequencei107 – 223117Missing in isoform 4. 2 PublicationsVSP_021985Add
BLAST
Alternative sequencei118 – 14831Missing in isoform 3. 2 PublicationsVSP_021986Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
U75283 mRNA. Translation: AAB50402.1.
U79528 mRNA. Translation: AAB51238.1.
AF001977, AF001976 Genomic DNA. Translation: AAC04507.1.
AF226604 mRNA. Translation: AAF64280.1.
AY633611 mRNA. Translation: AAV33304.1.
DQ644568 mRNA. Translation: ABG29111.1.
DQ647702 mRNA. Translation: ABG36559.1.
DQ656583 mRNA. Translation: ABG46369.1.
AK098451 mRNA. Translation: BAC05307.1.
CR457075 mRNA. Translation: CAG33356.1.
AK222899 mRNA. Translation: BAD96619.1.
AL450283 Genomic DNA. Translation: CAI14185.1.
CH471071 Genomic DNA. Translation: EAW58431.1.
CH471071 Genomic DNA. Translation: EAW58434.1.
BC004899 mRNA. Translation: AAH04899.1.
BC007839 mRNA. Translation: AAH07839.1.
CCDSiCCDS6562.1. [Q99720-1]
CCDS6563.1. [Q99720-3]
PIRiJC5266.
RefSeqiNP_001269134.1. NM_001282205.1.
NP_001269135.1. NM_001282206.1.
NP_001269136.1. NM_001282207.1. [Q99720-2]
NP_001269137.1. NM_001282208.1.
NP_001269138.1. NM_001282209.1.
NP_005857.1. NM_005866.3. [Q99720-1]
NP_671513.1. NM_147157.2. [Q99720-3]
UniGeneiHs.522087.

Genome annotation databases

EnsembliENST00000277010; ENSP00000277010; ENSG00000147955. [Q99720-1]
ENST00000353468; ENSP00000434453; ENSG00000147955. [Q99720-4]
ENST00000477726; ENSP00000420022; ENSG00000147955. [Q99720-3]
GeneIDi10280.
KEGGihsa:10280.
UCSCiuc003zvb.5. human. [Q99720-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Web resourcesi

Wikipedia

Sigma-1 receptor entry

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
U75283 mRNA. Translation: AAB50402.1.
U79528 mRNA. Translation: AAB51238.1.
AF001977, AF001976 Genomic DNA. Translation: AAC04507.1.
AF226604 mRNA. Translation: AAF64280.1.
AY633611 mRNA. Translation: AAV33304.1.
DQ644568 mRNA. Translation: ABG29111.1.
DQ647702 mRNA. Translation: ABG36559.1.
DQ656583 mRNA. Translation: ABG46369.1.
AK098451 mRNA. Translation: BAC05307.1.
CR457075 mRNA. Translation: CAG33356.1.
AK222899 mRNA. Translation: BAD96619.1.
AL450283 Genomic DNA. Translation: CAI14185.1.
CH471071 Genomic DNA. Translation: EAW58431.1.
CH471071 Genomic DNA. Translation: EAW58434.1.
BC004899 mRNA. Translation: AAH04899.1.
BC007839 mRNA. Translation: AAH07839.1.
CCDSiCCDS6562.1. [Q99720-1]
CCDS6563.1. [Q99720-3]
PIRiJC5266.
RefSeqiNP_001269134.1. NM_001282205.1.
NP_001269135.1. NM_001282206.1.
NP_001269136.1. NM_001282207.1. [Q99720-2]
NP_001269137.1. NM_001282208.1.
NP_001269138.1. NM_001282209.1.
NP_005857.1. NM_005866.3. [Q99720-1]
NP_671513.1. NM_147157.2. [Q99720-3]
UniGeneiHs.522087.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
5HK1X-ray2.51A/B/C1-223[»]
5HK2X-ray3.20A/B/C1-223[»]
ProteinModelPortaliQ99720.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi115569. 12 interactions.
IntActiQ99720. 3 interactions.
STRINGi9606.ENSP00000277010.

Chemistry

BindingDBiQ99720.
ChEMBLiCHEMBL287.
DrugBankiDB00321. Amitriptyline.
DB09014. Captodiame.
DB00514. Dextromethorphan.
DB00540. Nortriptyline.
DB00652. Pentazocine.
DB00409. Remoxipride.
GuidetoPHARMACOLOGYi2552.

Protein family/group databases

TCDBi8.A.63.1.1. the sigma non-opioid intracellular recpetor, (sigma-1) family.

PTM databases

iPTMnetiQ99720.
PhosphoSiteiQ99720.

Polymorphism and mutation databases

DMDMi74752153.

Proteomic databases

EPDiQ99720.
MaxQBiQ99720.
PaxDbiQ99720.
PeptideAtlasiQ99720.
PRIDEiQ99720.
TopDownProteomicsiQ99720-1. [Q99720-1]
Q99720-2. [Q99720-2]
Q99720-3. [Q99720-3]
Q99720-4. [Q99720-4]
Q99720-5. [Q99720-5]

Protocols and materials databases

DNASUi10280.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000277010; ENSP00000277010; ENSG00000147955. [Q99720-1]
ENST00000353468; ENSP00000434453; ENSG00000147955. [Q99720-4]
ENST00000477726; ENSP00000420022; ENSG00000147955. [Q99720-3]
GeneIDi10280.
KEGGihsa:10280.
UCSCiuc003zvb.5. human. [Q99720-1]

Organism-specific databases

CTDi10280.
GeneCardsiSIGMAR1.
H-InvDBHIX0008000.
HIX0169361.
HGNCiHGNC:8157. SIGMAR1.
HPAiCAB013470.
HPA018002.
HPA024071.
MalaCardsiSIGMAR1.
MIMi601978. gene.
605726. phenotype.
614373. phenotype.
neXtProtiNX_Q99720.
Orphaneti300605. Juvenile amyotrophic lateral sclerosis.
PharmGKBiPA164725706.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG4143. Eukaryota.
ENOG410XP0Z. LUCA.
GeneTreeiENSGT00390000012082.
HOVERGENiHBG058220.
InParanoidiQ99720.
OMAiLFYTLRA.
OrthoDBiEOG091G0KD7.
PhylomeDBiQ99720.
TreeFamiTF300106.

Miscellaneous databases

ChiTaRSiSIGMAR1. human.
GeneWikiiSigma-1_receptor.
GenomeRNAii10280.
PROiQ99720.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000147955.
ExpressionAtlasiQ99720. baseline and differential.
GenevisibleiQ99720. HS.

Family and domain databases

InterProiIPR006716. ERG2_sigma1_rcpt-like.
[Graphical view]
PfamiPF04622. ERG2_Sigma1R. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiSGMR1_HUMAN
AccessioniPrimary (citable) accession number: Q99720
Secondary accession number(s): D3DRM7
, O00673, O00725, Q0Z9W6, Q153Z1, Q2TSD1, Q53GN2, Q7Z653, Q8N7H3, Q9NYX0
Entry historyi
Integrated into UniProtKB/Swiss-Prot: December 12, 2006
Last sequence update: May 1, 1997
Last modified: September 7, 2016
This is version 135 of the entry and version 1 of the sequence. [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

Miscellaneous

Depletion by RNAi inhibits growth and survival signaling cascades and induces cell death. The antagonist rimcazole produces the same effect.

Caution

The NMR solution structure identifies a second transmembrane helix starting with Gly-91 (PubMed:25647032). The X-ray structure clearly shows that this region is not helical and not in the membrane; instead it is part of two beta-strands (PubMed:27042935).2 Publications

Keywords - Technical termi

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

Documents

  1. Human chromosome 9
    Human chromosome 9: 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. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  6. SIMILARITY comments
    Index of protein domains and families

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.