UniProtKB - Q9GZX7 (AICDA_HUMAN)
Single-stranded DNA cytosine deaminase
AICDA
Functioni
Single-stranded DNA-specific cytidine deaminase. Involved in somatic hypermutation (SHM), gene conversion, and class-switch recombination (CSR) in B-lymphocytes by deaminating C to U during transcription of Ig-variable (V) and Ig-switch (S) region DNA. Required for several crucial steps of B-cell terminal differentiation necessary for efficient antibody responses (PubMed:18722174, PubMed:21385873, PubMed:21518874, PubMed:27716525).
May also play a role in the epigenetic regulation of gene expression by participating in DNA demethylation (PubMed:21496894).
5 PublicationsCatalytic activityi
- a 2'-deoxycytidine in single-stranded DNA + H+ + H2O = a 2'-deoxyuridine in single-stranded DNA + NH4+1 PublicationEC:3.5.4.381 Publication
Cofactori
Sites
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Metal bindingi | 56 | Zinc; catalytic1 Publication | 1 | |
Active sitei | 58 | Proton donorBy similarity | 1 | |
Metal bindingi | 87 | Zinc; catalytic1 Publication | 1 | |
Metal bindingi | 90 | Zinc; catalytic1 Publication | 1 |
GO - Molecular functioni
- cytidine deaminase activity Source: UniProtKB
- deoxycytidine deaminase activity Source: GO_Central
- identical protein binding Source: IntAct
- RNA binding Source: GO_Central
- ubiquitin protein ligase binding Source: UniProtKB
- zinc ion binding Source: InterPro
GO - Biological processi
- B cell differentiation Source: UniProtKB
- cellular response to lipopolysaccharide Source: Ensembl
- cytidine to uridine editing Source: GO_Central
- defense response to bacterium Source: Ensembl
- defense response to virus Source: GO_Central
- DNA cytosine deamination Source: GO_Central
- DNA demethylation Source: UniProtKB
- isotype switching Source: Ensembl
- mRNA processing Source: UniProtKB-KW
- negative regulation of DNA methylation-dependent heterochromatin assembly Source: UniProtKB
- negative regulation of single stranded viral RNA replication via double stranded DNA intermediate Source: GO_Central
- negative regulation of transposition Source: GO_Central
- regulation of nuclear cell cycle DNA replication Source: UniProtKB
- somatic diversification of immunoglobulins Source: UniProtKB
- somatic hypermutation of immunoglobulin genes Source: UniProtKB
Keywordsi
Molecular function | Hydrolase |
Biological process | mRNA processing |
Ligand | Metal-binding, Zinc |
Enzyme and pathway databases
BRENDAi | 3.5.4.38, 2681 |
PathwayCommonsi | Q9GZX7 |
SignaLinki | Q9GZX7 |
SIGNORi | Q9GZX7 |
Names & Taxonomyi
Protein namesi | Recommended name: Single-stranded DNA cytosine deaminase (EC:3.5.4.381 Publication)Alternative name(s): Activation-induced cytidine deaminase Short name: AID Cytidine aminohydrolase |
Gene namesi | Name:AICDA Synonyms:AID |
Organismi | Homo sapiens (Human) |
Taxonomic identifieri | 9606 [NCBI] |
Taxonomic lineagei | Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo |
Proteomesi |
|
Organism-specific databases
HGNCi | HGNC:13203, AICDA |
MIMi | 605257, gene |
neXtProti | NX_Q9GZX7 |
VEuPathDBi | HostDB:ENSG00000111732 |
Subcellular locationi
Nucleus
- nucleus Source: UniProtKB
Other locations
- cytoplasm Source: UniProtKB
- P-body Source: GO_Central
- protein-containing complex Source: GO_Central
Keywords - Cellular componenti
Cytoplasm, NucleusPathology & Biotechi
Involvement in diseasei
Immunodeficiency with hyper-IgM 2 (HIGM2)5 Publications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Natural variantiVAR_077563 | 15 | F → L in HIGM2. 1 Publication | 1 | |
Natural variantiVAR_013774 | 24 | R → W in HIGM2; completely abolishes nuclear import and interaction with CTNNBL1, diminishes interaction with KPNA1 and abolishes immunoglobulin class switching. 3 PublicationsCorresponds to variant dbSNP:rs104894324EnsemblClinVar. | 1 | |
Natural variantiVAR_077564 | 31 | Y → H in HIGM2. 1 Publication | 1 | |
Natural variantiVAR_077565 | 56 | H → Y in HIGM2; unknown pathological significance; loss of mutagenic activity. 2 Publications | 1 | |
Natural variantiVAR_013775 | 80 | W → R in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894320EnsemblClinVar. | 1 | |
Natural variantiVAR_077566 | 87 | C → R in HIGM2; unknown pathological significance. 1 PublicationCorresponds to variant dbSNP:rs762590894EnsemblClinVar. | 1 | |
Natural variantiVAR_013776 | 106 | L → P in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894321EnsemblClinVar. | 1 | |
Natural variantiVAR_077567 | 130 | H → P in HIGM2; slightly decreased mutagenic activity. 2 Publications | 1 | |
Natural variantiVAR_013777 | 139 | M → V in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894322EnsemblClinVar. | 1 | |
Natural variantiVAR_013778 | 151 | F → S in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894327EnsemblClinVar. | 1 | |
Natural variantiVAR_077568 | 174 | R → S in HIGM2; unknown pathological significance. 1 Publication | 1 |
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 10 | K → A: Little effect on nuclear import; when associated with A-193. No effect on CTNNBL1 binding. 1 Publication | 1 | |
Mutagenesisi | 18 | V → S: Greatly impaired nuclear import; when associated with V-19 and A-193. Reduced interaction with both CTNNBL1 and KPNA1, and abolishes immunoglobulin class switching; when associated with V-19. 1 Publication | 1 | |
Mutagenesisi | 19 | R → V: Greatly impaired nuclear import; when associated with S-18 and A-193. Reduced interaction with both CTNNBL1 and KPNA1, and abolishes immunoglobulin class switching; when associated with S-18. 1 Publication | 1 | |
Mutagenesisi | 20 | W → K: Impaired nuclear import; when associated with A-193. No effect on CTNNBL1 binding. 1 Publication | 1 | |
Mutagenesisi | 27 | T → A: Loss of phosphorylation. No effect on cytidine deaminase activity. Impaired class-switch recombination activity. 2 Publications | 1 | |
Mutagenesisi | 27 | T → E: Phosphomimetic mutant which shows loss of cytidine deaminase activity and impaired class-switch recombination activity. 2 Publications | 1 | |
Mutagenesisi | 38 | S → A: Loss of phosphorylation. Impaired class-switch recombination activity. No effect on interaction with CTNNBL1. 2 Publications | 1 | |
Mutagenesisi | 38 | S → D: No effect on interaction with CTNNBL1. 2 Publications | 1 | |
Mutagenesisi | 39 – 42 | ATSF → GGQV: Greatly reduced interaction with CTNNBL1 but no effect on subcellular location, enzyme activity, ability to oligomerize nor on phosphorylation at Ser-38. Diminished antibody diversification. 1 Publication | 4 | |
Mutagenesisi | 50 | R → G: Some reduced nuclear import; when associated with A-193. 1 Publication | 1 | |
Mutagenesisi | 112 | R → D: Greatly reduced nuclear import; when associated with A-193. 1 Publication | 1 | |
Mutagenesisi | 193 | F → A: Completely abolishes nuclear import; when associated with W-24 or D-112. Little affect on nuclear import; when associated with A-10. Greatly impaired nuclear import; when associated with K-20 or G-50. Almost completely abolishes nuclear import; when associated with S-18 and V-19. 1 Publication | 1 |
Keywords - Diseasei
Disease variantOrganism-specific databases
DisGeNETi | 57379 |
MalaCardsi | AICDA |
MIMi | 605258, phenotype |
OpenTargetsi | ENSG00000111732 |
Orphaneti | 101089, Hyper-IgM syndrome type 2 |
PharmGKBi | PA24644 |
Miscellaneous databases
Pharosi | Q9GZX7, Tbio |
Genetic variation databases
BioMutai | AICDA |
DMDMi | 23813666 |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
ChainiPRO_0000171687 | 1 – 198 | Single-stranded DNA cytosine deaminaseAdd BLAST | 198 |
Amino acid modifications
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Modified residuei | 27 | Phosphothreonine; by PKA1 Publication | 1 | |
Modified residuei | 38 | Phosphoserine; by PKA2 Publications | 1 |
Post-translational modificationi
Keywords - PTMi
Phosphoprotein, Ubl conjugationProteomic databases
MassIVEi | Q9GZX7 |
MaxQBi | Q9GZX7 |
PaxDbi | Q9GZX7 |
PeptideAtlasi | Q9GZX7 |
PRIDEi | Q9GZX7 |
ProteomicsDBi | 67301 80168 [Q9GZX7-1] |
PTM databases
iPTMneti | Q9GZX7 |
PhosphoSitePlusi | Q9GZX7 |
Expressioni
Tissue specificityi
Inductioni
Gene expression databases
Bgeei | ENSG00000111732, Expressed in tonsil and 89 other tissues |
ExpressionAtlasi | Q9GZX7, baseline and differential |
Genevisiblei | Q9GZX7, HS |
Organism-specific databases
HPAi | ENSG00000111732, Tissue enriched (lymphoid) |
Interactioni
Subunit structurei
Interacts with CTNNBL1; the interaction is important for the immunoglobulin switch activity of AICDA (PubMed:18722174, PubMed:21385873).
Interacts (via its NLS) with KPNA1.
Interacts with PKA/PRKACA and PRKAR1A/PKR1 (PubMed:16387847).
Interacts with TRIM28 and NCL (By similarity).
Interacts with SUPT6H (PubMed:21518874).
Interacts with RNF126 (PubMed:23277564). Directly interacts with MCM3AP; this interaction may favor AICDA recruitment to immunoglobulin variable region genes, hence promoting somatic hypermutations (PubMed:20507984).
By similarity6 PublicationsBinary interactionsi
Q9GZX7
GO - Molecular functioni
- identical protein binding Source: IntAct
- ubiquitin protein ligase binding Source: UniProtKB
Protein-protein interaction databases
BioGRIDi | 121497, 55 interactors |
DIPi | DIP-48519N |
ELMi | Q9GZX7 |
IntActi | Q9GZX7, 31 interactors |
MINTi | Q9GZX7 |
STRINGi | 9606.ENSP00000229335 |
Miscellaneous databases
RNActi | Q9GZX7, protein |
Structurei
Secondary structure
3D structure databases
SMRi | Q9GZX7 |
ModBasei | Search... |
PDBe-KBi | Search... |
Family & Domainsi
Domains and Repeats
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Domaini | 23 – 129 | CMP/dCMP-type deaminasePROSITE-ProRule annotationAdd BLAST | 107 |
Region
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Regioni | 2 – 26 | Interaction with SUPT6H1 PublicationAdd BLAST | 25 | |
Regioni | 39 – 42 | Important for interaction with CTNNBL11 Publication | 4 | |
Regioni | 88 – 116 | Required for interaction with RNF1261 PublicationAdd BLAST | 29 |
Motif
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Motifi | 1 – 30 | Bipartite nuclear localization signal1 PublicationAdd BLAST | 30 | |
Motifi | 183 – 198 | Nuclear export signal1 PublicationAdd BLAST | 16 |
Sequence similaritiesi
Phylogenomic databases
eggNOGi | KOG4075, Eukaryota |
GeneTreei | ENSGT00940000158731 |
InParanoidi | Q9GZX7 |
OMAi | AARLYFC |
PhylomeDBi | Q9GZX7 |
TreeFami | TF331356 |
Family and domain databases
InterProi | View protein in InterPro IPR016192, APOBEC/CMP_deaminase_Zn-bd IPR002125, CMP_dCMP_dom IPR016193, Cytidine_deaminase-like |
SUPFAMi | SSF53927, SSF53927, 1 hit |
PROSITEi | View protein in PROSITE PS00903, CYT_DCMP_DEAMINASES_1, 1 hit PS51747, CYT_DCMP_DEAMINASES_2, 1 hit |
s (2+)i Sequence
Sequence statusi: Complete.
This entry describes 2 produced by isoformsialternative splicing. AlignAdd to basketThis entry has 2 described isoforms and 3 potential isoforms that are computationally mapped.Show allAlign All
This isoform has been chosen as the sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry. canonicali
10 20 30 40 50
MDSLLMNRRK FLYQFKNVRW AKGRRETYLC YVVKRRDSAT SFSLDFGYLR
60 70 80 90 100
NKNGCHVELL FLRYISDWDL DPGRCYRVTW FTSWSPCYDC ARHVADFLRG
110 120 130 140 150
NPNLSLRIFT ARLYFCEDRK AEPEGLRRLH RAGVQIAIMT FKDYFYCWNT
160 170 180 190
FVENHERTFK AWEGLHENSV RLSRQLRRIL LPLYEVDDLR DAFRTLGL
Computationally mapped potential isoform sequencesi
There are 3 potential isoforms mapped to this entry.BLASTAlignShow allAdd to basketH0YGF6 | H0YGF6_HUMAN | Single-stranded DNA cytosine deamin... | AICDA | 197 | Annotation score: | ||
H0YFL3 | H0YFL3_HUMAN | Single-stranded DNA cytosine deamin... | AICDA | 144 | Annotation score: | ||
H0YFP1 | H0YFP1_HUMAN | Single-stranded DNA cytosine deamin... | AICDA | 68 | Annotation score: |
Experimental Info
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Sequence conflicti | 119 | R → H in AAM95406 (PubMed:12202747).Curated | 1 |
Natural variant
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Natural variantiVAR_077563 | 15 | F → L in HIGM2. 1 Publication | 1 | |
Natural variantiVAR_013774 | 24 | R → W in HIGM2; completely abolishes nuclear import and interaction with CTNNBL1, diminishes interaction with KPNA1 and abolishes immunoglobulin class switching. 3 PublicationsCorresponds to variant dbSNP:rs104894324EnsemblClinVar. | 1 | |
Natural variantiVAR_014091 | 25 | R → C1 PublicationCorresponds to variant dbSNP:rs1404944797Ensembl. | 1 | |
Natural variantiVAR_077564 | 31 | Y → H in HIGM2. 1 Publication | 1 | |
Natural variantiVAR_077565 | 56 | H → Y in HIGM2; unknown pathological significance; loss of mutagenic activity. 2 Publications | 1 | |
Natural variantiVAR_013775 | 80 | W → R in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894320EnsemblClinVar. | 1 | |
Natural variantiVAR_077566 | 87 | C → R in HIGM2; unknown pathological significance. 1 PublicationCorresponds to variant dbSNP:rs762590894EnsemblClinVar. | 1 | |
Natural variantiVAR_013776 | 106 | L → P in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894321EnsemblClinVar. | 1 | |
Natural variantiVAR_077567 | 130 | H → P in HIGM2; slightly decreased mutagenic activity. 2 Publications | 1 | |
Natural variantiVAR_013777 | 139 | M → V in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894322EnsemblClinVar. | 1 | |
Natural variantiVAR_013778 | 151 | F → S in HIGM2. 2 PublicationsCorresponds to variant dbSNP:rs104894327EnsemblClinVar. | 1 | |
Natural variantiVAR_077568 | 174 | R → S in HIGM2; unknown pathological significance. 1 Publication | 1 |
Alternative sequence
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Alternative sequenceiVSP_047803 | 143 – 152 | Missing in isoform 2. 1 Publication | 10 |
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | AB040431 mRNA Translation: BAB12721.1 AB040430 Genomic DNA Translation: BAB12720.1 AF529819 mRNA Translation: AAM95406.1 AY536516 mRNA Translation: AAS92920.1 BT007402 mRNA Translation: AAP36066.1 AC092184 Genomic DNA No translation available. BC006296 mRNA Translation: AAH06296.1 |
CCDSi | CCDS41747.1 [Q9GZX7-1] CCDS81662.1 [Q9GZX7-2] |
RefSeqi | NP_001317272.1, NM_001330343.1 [Q9GZX7-2] NP_065712.1, NM_020661.3 [Q9GZX7-1] |
Genome annotation databases
Ensembli | ENST00000229335; ENSP00000229335; ENSG00000111732 ENST00000537228; ENSP00000445691; ENSG00000111732 [Q9GZX7-2] |
GeneIDi | 57379 |
KEGGi | hsa:57379 |
MANE-Selecti | ENST00000229335.11; ENSP00000229335.6; NM_020661.4; NP_065712.1 |
UCSCi | uc001qur.3, human [Q9GZX7-1] |
Keywords - Coding sequence diversityi
Alternative splicingSimilar proteinsi
Cross-referencesi
Web resourcesi
AICDAbase AICDA mutation db |
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | AB040431 mRNA Translation: BAB12721.1 AB040430 Genomic DNA Translation: BAB12720.1 AF529819 mRNA Translation: AAM95406.1 AY536516 mRNA Translation: AAS92920.1 BT007402 mRNA Translation: AAP36066.1 AC092184 Genomic DNA No translation available. BC006296 mRNA Translation: AAH06296.1 |
CCDSi | CCDS41747.1 [Q9GZX7-1] CCDS81662.1 [Q9GZX7-2] |
RefSeqi | NP_001317272.1, NM_001330343.1 [Q9GZX7-2] NP_065712.1, NM_020661.3 [Q9GZX7-1] |
3D structure databases
Select the link destinations: PDBei RCSB PDBi PDBji Links Updated | PDB entry | Method | Resolution (Å) | Chain | Positions | PDBsum |
5JJ4 | X-ray | 2.81 | A/B/C | 23-183 | [»] | |
5W0R | X-ray | 2.40 | A/B | 13-181 | [»] | |
5W0U | X-ray | 2.90 | A/B | 13-181 | [»] | |
5W0Z | X-ray | 3.61 | A/B | 13-181 | [»] | |
5W1C | X-ray | 3.18 | A/B | 5-181 | [»] | |
SMRi | Q9GZX7 | |||||
ModBasei | Search... | |||||
PDBe-KBi | Search... |
Protein-protein interaction databases
BioGRIDi | 121497, 55 interactors |
DIPi | DIP-48519N |
ELMi | Q9GZX7 |
IntActi | Q9GZX7, 31 interactors |
MINTi | Q9GZX7 |
STRINGi | 9606.ENSP00000229335 |
PTM databases
iPTMneti | Q9GZX7 |
PhosphoSitePlusi | Q9GZX7 |
Genetic variation databases
BioMutai | AICDA |
DMDMi | 23813666 |
Proteomic databases
MassIVEi | Q9GZX7 |
MaxQBi | Q9GZX7 |
PaxDbi | Q9GZX7 |
PeptideAtlasi | Q9GZX7 |
PRIDEi | Q9GZX7 |
ProteomicsDBi | 67301 80168 [Q9GZX7-1] |
Protocols and materials databases
Antibodypediai | 6178, 436 antibodies from 43 providers |
DNASUi | 57379 |
Genome annotation databases
Ensembli | ENST00000229335; ENSP00000229335; ENSG00000111732 ENST00000537228; ENSP00000445691; ENSG00000111732 [Q9GZX7-2] |
GeneIDi | 57379 |
KEGGi | hsa:57379 |
MANE-Selecti | ENST00000229335.11; ENSP00000229335.6; NM_020661.4; NP_065712.1 |
UCSCi | uc001qur.3, human [Q9GZX7-1] |
Organism-specific databases
CTDi | 57379 |
DisGeNETi | 57379 |
GeneCardsi | AICDA |
HGNCi | HGNC:13203, AICDA |
HPAi | ENSG00000111732, Tissue enriched (lymphoid) |
MalaCardsi | AICDA |
MIMi | 605257, gene 605258, phenotype |
neXtProti | NX_Q9GZX7 |
OpenTargetsi | ENSG00000111732 |
Orphaneti | 101089, Hyper-IgM syndrome type 2 |
PharmGKBi | PA24644 |
VEuPathDBi | HostDB:ENSG00000111732 |
GenAtlasi | Search... |
Phylogenomic databases
eggNOGi | KOG4075, Eukaryota |
GeneTreei | ENSGT00940000158731 |
InParanoidi | Q9GZX7 |
OMAi | AARLYFC |
PhylomeDBi | Q9GZX7 |
TreeFami | TF331356 |
Enzyme and pathway databases
BRENDAi | 3.5.4.38, 2681 |
PathwayCommonsi | Q9GZX7 |
SignaLinki | Q9GZX7 |
SIGNORi | Q9GZX7 |
Miscellaneous databases
BioGRID-ORCSi | 57379, 5 hits in 1033 CRISPR screens |
ChiTaRSi | AICDA, human |
GeneWikii | AICDA |
GenomeRNAii | 57379 |
Pharosi | Q9GZX7, Tbio |
PROi | PR:Q9GZX7 |
RNActi | Q9GZX7, protein |
SOURCEi | Search... |
Gene expression databases
Bgeei | ENSG00000111732, Expressed in tonsil and 89 other tissues |
ExpressionAtlasi | Q9GZX7, baseline and differential |
Genevisiblei | Q9GZX7, HS |
Family and domain databases
InterProi | View protein in InterPro IPR016192, APOBEC/CMP_deaminase_Zn-bd IPR002125, CMP_dCMP_dom IPR016193, Cytidine_deaminase-like |
SUPFAMi | SSF53927, SSF53927, 1 hit |
PROSITEi | View protein in PROSITE PS00903, CYT_DCMP_DEAMINASES_1, 1 hit PS51747, CYT_DCMP_DEAMINASES_2, 1 hit |
MobiDBi | Search... |
Entry informationi
Entry namei | AICDA_HUMAN | |
Accessioni | Q9GZX7Primary (citable) accession number: Q9GZX7 Secondary accession number(s): Q6QJ81, Q8NFC1 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | October 10, 2002 |
Last sequence update: | March 1, 2001 | |
Last modified: | February 23, 2022 | |
This is version 176 of the entry and version 1 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Chordata Protein Annotation Program | |
Disclaimer | Any 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, Reference proteomeDocuments
- Human chromosome 12
Human chromosome 12: entries, gene names and cross-references to MIM - Human entries with genetic variants
List of human entries with genetic variants - Human variants curated from literature reports
Index of human variants curated from literature reports - MIM cross-references
Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot - PDB cross-references
Index of Protein Data Bank (PDB) cross-references - SIMILARITY comments
Index of protein domains and families