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Aliases for ASS1 Gene

Aliases for ASS1 Gene

  • Argininosuccinate Synthase 1 2 3 5
  • EC 4 58
  • ASS 3 4
  • Argininosuccinate Synthetase 1 3
  • Argininosuccinate Synthetase 2
  • Citrulline--Aspartate Ligase 4
  • Citrulline-Aspartate Ligase 3
  • Argininosuccinate Synthase 3
  • CTLN1 3

External Ids for ASS1 Gene

Previous HGNC Symbols for ASS1 Gene

  • ASS

Previous GeneCards Identifiers for ASS1 Gene

  • GC09P132310
  • GC09P133320
  • GC09P102805

Summaries for ASS1 Gene

Entrez Gene Summary for ASS1 Gene

  • The protein encoded by this gene catalyzes the penultimate step of the arginine biosynthetic pathway. There are approximately 10 to 14 copies of this gene including the pseudogenes scattered across the human genome, among which the one located on chromosome 9 appears to be the only functional gene for argininosuccinate synthetase. Mutations in the chromosome 9 copy of this gene cause citrullinemia. Two transcript variants encoding the same protein have been found for this gene. [provided by RefSeq, Aug 2012]

GeneCards Summary for ASS1 Gene

ASS1 (Argininosuccinate Synthase 1) is a Protein Coding gene. Diseases associated with ASS1 include Citrullinemia and Acute Neonatal Citrullinemia Type I. Among its related pathways are CDK-mediated phosphorylation and removal of Cdc6 and Metabolism. GO annotations related to this gene include poly(A) RNA binding and amino acid binding.

UniProtKB/Swiss-Prot for ASS1 Gene

  • One of the enzymes of the urea cycle, the metabolic pathway transforming neurotoxic amonia produced by protein catabolism into inocuous urea in the liver of ureotelic animals. Catalyzes the formation of arginosuccinate from aspartate, citrulline and ATP and together with ASL it is responsible for the biosynthesis of arginine in most body tissues.

Gene Wiki entry for ASS1 Gene

Additional gene information for ASS1 Gene

No data available for CIViC summary , Tocris Summary , PharmGKB "VIP" Summary , fRNAdb sequence ontologies and piRNA Summary for ASS1 Gene

Genomics for ASS1 Gene

Regulatory Elements for ASS1 Gene

Enhancers for ASS1 Gene
GeneHancer Identifier Enhancer Score Enhancer Sources Gene-Enhancer Score TSS distance (kb) Number of Genes Away Size (kb) Transcription Factor Binding Sites within enhancer Gene Targets for Enhancer
GH09H130444 2 FANTOM5 Ensembl ENCODE dbSUPER 3.4 +3.8 3804 8.4 FOXA2 PKNOX1 MLX ZFP64 ARID4B SIN3A FEZF1 DMAP1 ZNF2 YY1 NUP214 EXOSC2 ENSG00000246851 FUBP3 TOR1B ENSG00000236986 ASS1 GC09M130482
GH09H130480 0.9 ENCODE dbSUPER 5.3 +36.2 36172 0.2 CTCF RB1 REST RAD21 TEAD3 CC2D1A ZBTB33 KDM1A ZFX PRDM12 FUBP3 ABL1 FIBCD1 LOC105376297 ASS1 GC09M130482
GH09H130351 0.4 ENCODE 7.8 -92.4 -92417 1 FOS ASS1 RN7SL665P GC09M130264
GH09H130431 1.2 Ensembl ENCODE 0.4 -11.7 -11654 2.3 FOXA2 SIN3A KLF17 GLI4 THRB RAD21 RARA YY1 GLIS2 ZNF143 HMCN2 FUBP3 ASS1 RN7SL665P
GH09H130454 1 ENCODE dbSUPER 0.4 +9.0 8992 0.2 SAP130 NFIB ZIC2 RARA GLIS2 NR2F6 RCOR1 GATAD2A NFIA BHLHE40 ASS1 GC09M130482
- Elite enhancer and/or Elite enhancer-gene association Download GeneHancer data dump

Enhancers around ASS1 on UCSC Golden Path with GeneCards custom track

Promoters for ASS1 Gene
Ensembl Regulatory Elements (ENSRs) TSS Distance (bp) Size (bp) Binding Sites for Transcription Factors within promoters
ENSR00000242205 493 1201 ARID4B SIN3A FEZF1 YY1 GLIS2 DEK SP3 SP5 REST GLIS1

Transcription factor binding sites by QIAGEN in the ASS1 gene promoter:

Genomic Locations for ASS1 Gene

Genomic Locations for ASS1 Gene
56,568 bases
Plus strand

Genomic View for ASS1 Gene

Genes around ASS1 on UCSC Golden Path with GeneCards custom track

Cytogenetic band:
ASS1 Gene in genomic location: bands according to Ensembl, locations according to GeneLoc (and/or Entrez Gene and/or Ensembl if different)
Genomic Location for ASS1 Gene
GeneLoc Logo Genomic Neighborhood Exon StructureGene Density

RefSeq DNA sequence for ASS1 Gene

Proteins for ASS1 Gene

  • Protein details for ASS1 Gene (UniProtKB/Swiss-Prot)

    Protein Symbol:
    Recommended name:
    Argininosuccinate synthase
    Protein Accession:
    Secondary Accessions:
    • Q6LDL2
    • Q86UZ0
    • Q96GT4

    Protein attributes for ASS1 Gene

    412 amino acids
    Molecular mass:
    46530 Da
    Quaternary structure:
    • Homotetramer (PubMed:18323623). Interacts with NMRAL1 (PubMed:17496144).

    Three dimensional structures from OCA and Proteopedia for ASS1 Gene

neXtProt entry for ASS1 Gene

Selected DME Specific Peptides for ASS1 Gene


Post-translational modifications for ASS1 Gene

  • Modification sites at PhosphoSitePlus
  • Modification sites at neXtProt

Antibody Products

  • Cell Signaling Technology (CST) Antibodies for ASS1 (ASS1)
  • Abcam antibodies for ASS1

Domains & Families for ASS1 Gene

Gene Families for ASS1 Gene

Human Protein Atlas (HPA):
  • Disease related genes
  • Enzymes
  • Plasma proteins
  • Potential drug targets
  • Predicted intracellular proteins

Graphical View of Domain Structure for InterPro Entry



  • Belongs to the argininosuccinate synthase family. Type 1 subfamily.
  • Belongs to the argininosuccinate synthase family. Type 1 subfamily.
genes like me logo Genes that share domains with ASS1: view

Function for ASS1 Gene

Molecular function for ASS1 Gene

UniProtKB/Swiss-Prot BiophysicochemicalProperties:
Kinetic parameters: KM=112 uM for citrulline (at pH 7.0 and 37 degrees Celsius) {ECO:0000269 PubMed:18473344}; KM=68 uM for aspartate (at pH 7.0 and 37 degrees Celsius) {ECO:0000269 PubMed:18473344}; Vmax=143 nmol/min/mg enzyme toward citrulline (at pH 7.0 and 37 degrees Celsius) {ECO:0000269 PubMed:18473344}; Vmax=116 nmol/min/mg enzyme toward aspartate (at pH 7.0 and 37 degrees {ECO:0000269 PubMed:18473344};
UniProtKB/Swiss-Prot CatalyticActivity:
ATP + L-citrulline + L-aspartate = AMP + diphosphate + N(omega)-(L-arginino)succinate.
UniProtKB/Swiss-Prot Function:
One of the enzymes of the urea cycle, the metabolic pathway transforming neurotoxic amonia produced by protein catabolism into inocuous urea in the liver of ureotelic animals. Catalyzes the formation of arginosuccinate from aspartate, citrulline and ATP and together with ASL it is responsible for the biosynthesis of arginine in most body tissues.

Enzyme Numbers (IUBMB) for ASS1 Gene

Gene Ontology (GO) - Molecular Function for ASS1 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0000166 nucleotide binding IEA --
GO:0003723 RNA binding IDA 22658674
GO:0004055 argininosuccinate synthase activity IEA,IMP 7977368
GO:0005515 protein binding IPI 12620389
GO:0005524 ATP binding IEA --
genes like me logo Genes that share ontologies with ASS1: view
genes like me logo Genes that share phenotypes with ASS1: view

Human Phenotype Ontology for ASS1 Gene

HPO Id HPO Name Alternative Ids Definition Synonyms

Animal Models for ASS1 Gene

MGI Knock Outs for ASS1:

Clone Products

No data available for Phenotypes From GWAS Catalog , Transcription Factor Targets and HOMER Transcription for ASS1 Gene

Localization for ASS1 Gene

Subcellular locations from UniProtKB/Swiss-Prot for ASS1 Gene

Cytoplasm, cytosol.

Subcellular locations from

Extracellular space Cytosol Plasma membrane Cytoskeleton Lysosome Endosome Peroxisome ER Golgi Apparatus Nucleus Mitochondrion 0 1 2 3 4 5 Confidence
COMPARTMENTS Subcellular localization image for ASS1 gene
Compartment Confidence
extracellular 5
cytosol 5
mitochondrion 4
nucleus 3
peroxisome 1

Subcellular locations from the

Human Protein Atlas (HPA)
  • Cytosol (2)
  • Nucleoplasm (2)
See all subcellular structures

Gene Ontology (GO) - Cellular Components for ASS1 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0005737 cytoplasm TAS 6194510
GO:0005739 mitochondrion IEA --
GO:0005829 cytosol TAS --
GO:0043209 myelin sheath IEA --
GO:0070062 extracellular exosome IDA 19056867
genes like me logo Genes that share ontologies with ASS1: view

Pathways & Interactions for ASS1 Gene

genes like me logo Genes that share pathways with ASS1: view

UniProtKB/Swiss-Prot P00966-ASSY_HUMAN

  • Pathway: Amino-acid biosynthesis; L-arginine biosynthesis; L-arginine from L-ornithine and carbamoyl phosphate: step 2/3.
  • Pathway: Nitrogen metabolism; urea cycle; (N(omega)-L-arginino)succinate from L-aspartate and L-citrulline: step 1/1.

Gene Ontology (GO) - Biological Process for ASS1 Gene

GO ID Qualified GO term Evidence PubMed IDs
GO:0000050 urea cycle TAS --
GO:0000052 citrulline metabolic process IMP 7977368
GO:0000053 argininosuccinate metabolic process IMP 7977368
GO:0006526 arginine biosynthetic process IMP,IEA 8792870
GO:0006531 aspartate metabolic process IMP 7977368
genes like me logo Genes that share ontologies with ASS1: view

No data available for SIGNOR curated interactions for ASS1 Gene

Drugs & Compounds for ASS1 Gene

(22) Drugs for ASS1 Gene - From: DrugBank, PharmGKB, HMDB, and Novoseek

Name Status Disease Links Group Role Mechanism of Action Clinical Trials
Citrulline Approved Nutra Full agonist, Agonist, Target 0
L-Arginine Approved Nutra Full agonist, Agonist, Target 0
L-Aspartic acid Approved Nutra Target 0
Phenylacetic acid Approved Pharma 12
Valproic Acid Approved, Investigational Pharma HDAC1 inhibitor, Histone deacetylase (HDAC)inhibitors 331

(15) Additional Compounds for ASS1 Gene - From: Novoseek and HMDB

Name Synonyms Role CAS Number PubChem IDs PubMed IDs
Argininosuccinic acid
  • 2-(N(Omega)-L-arginine)succinate
  • 2-(N(Omega)-L-arginine)succinic acid
  • 2-(N(Omega)-L-arginino)succinate
  • 2-(N(Omega)-L-arginino)succinic acid
  • 2-(Nw-L-arginino)butanedioate
  • Canavaninosuccinic acid
  • (4-)Diphosphoric acid ion
  • (P2O74-)Diphosphate
  • Diphosphate
  • Diphosphoric acid
  • PPi
genes like me logo Genes that share compounds with ASS1: view

Transcripts for ASS1 Gene

Unigene Clusters for ASS1 Gene

Argininosuccinate synthase 1:
Representative Sequences:

Clone Products

Alternative Splicing Database (ASD) splice patterns (SP) for ASS1 Gene

ExUns: 1a · 1b · 1c · 1d · 1e · 1f · 1g ^ 2 ^ 3 ^ 4 ^ 5 ^ 6 ^ 7 ^ 8 ^ 9a · 9b ^ 10 ^ 11 ^ 12a · 12b ^ 13a · 13b ^ 14 ^ 15 ^ 16a · 16b ^
SP1: - - - - - - -
SP2: - - - - - - - -
SP3: - - - - -
SP4: - - - - - - - - -
SP5: - - - -
SP6: -
SP7: - - - -
SP9: -
SP10: - -

ExUns: 17a · 17b ^ 18 ^ 19a · 19b · 19c
SP3: -

Relevant External Links for ASS1 Gene

GeneLoc Exon Structure for
ECgene alternative splicing isoforms for

Expression for ASS1 Gene

mRNA expression in normal human tissues from GTEx, Illumina, BioGPS, and CGAP SAGE for ASS1 Gene

mRNA differential expression in normal tissues according to GTEx for ASS1 Gene

This gene is overexpressed in Liver (x14.7) and Kidney - Cortex (x5.9).

Protein differential expression in normal tissues from HIPED for ASS1 Gene

This gene is overexpressed in Liver, secretome (18.5), Liver (14.5), and Kidney (11.2).

Integrated Proteomics: protein expression in normal tissues and cell lines from ProteomicsDB, PaxDb, MaxQB, and MOPED for ASS1 Gene

Protein tissue co-expression partners for ASS1 Gene

- Elite partner

NURSA nuclear receptor signaling pathways regulating expression of ASS1 Gene:


SOURCE GeneReport for Unigene cluster for ASS1 Gene:


mRNA Expression by UniProt/SwissProt for ASS1 Gene:

Tissue specificity: Expressed in adult liver.

Evidence on tissue expression from TISSUES for ASS1 Gene

  • Intestine(4.8)
  • Liver(4.8)
  • Muscle(4.8)
  • Kidney(4.6)
  • Nervous system(4.4)
  • Lung(3.7)
  • Eye(3)
  • Skin(2.8)
  • Heart(2.1)

Phenotype-based relationships between genes and organs from Gene ORGANizer for ASS1 Gene

Germ Layers:
  • ectoderm
  • endoderm
  • mesoderm
  • cardiovascular
  • digestive
  • nervous
  • respiratory
  • urinary
Head and neck:
  • brain
  • head
  • esophagus
  • lung
  • kidney
  • liver
  • stomach
  • blood
genes like me logo Genes that share expression patterns with ASS1: view

No data available for mRNA expression in embryonic tissues and stem cells from LifeMap Discovery for ASS1 Gene

Orthologs for ASS1 Gene

This gene was present in the common ancestor of eukaryotes.

Orthologs for ASS1 Gene

Organism Taxonomy Gene Similarity Type Details
(Pan troglodytes)
Mammalia ASS1 33 34
  • 99.51 (n)
(Mus musculus)
Mammalia Gm5424 34
  • 97 (a)
Ass1 33 16 34
  • 89.08 (n)
(Canis familiaris)
Mammalia ASS1 33 34
  • 92.15 (n)
(Bos Taurus)
Mammalia ASS1 33 34
  • 91.75 (n)
(Rattus norvegicus)
Mammalia Ass1 33
  • 89.64 (n)
(Monodelphis domestica)
Mammalia ASS1 34
  • 88 (a)
(Ornithorhynchus anatinus)
Mammalia ASS1 34
  • 81 (a)
(Gallus gallus)
Aves ASS1 33 34
  • 79.14 (n)
tropical clawed frog
(Silurana tropicalis)
Amphibia ass1 33
  • 75.17 (n)
African clawed frog
(Xenopus laevis)
Amphibia ass-prov 33
(Danio rerio)
Actinopterygii ass1 33 34
  • 74.39 (n)
rainbow trout
(Oncorhynchus mykiss)
Actinopterygii Omy.4283 33
fruit fly
(Drosophila melanogaster)
Insecta CG1315 33 34
  • 61.18 (n)
African malaria mosquito
(Anopheles gambiae)
Insecta ASSY_ANOGA 33
  • 60.79 (n)
A. gosspyii yeast
(Ashbya gossypii)
Saccharomycetes AGOS_AER230C 33
  • 55.19 (n)
K. lactis yeast
(Kluyveromyces lactis)
Saccharomycetes KLLA0C04037g 33
  • 54.02 (n)
baker's yeast
(Saccharomyces cerevisiae)
Saccharomycetes ARG1 33 34 36
  • 53.5 (n)
thale cress
(Arabidopsis thaliana)
eudicotyledons AT4G24830 33
  • 52.99 (n)
(Oryza sativa)
Liliopsida Os12g0235800 33
  • 53.4 (n)
(Triticum aestivum)
Liliopsida Ta.9270 33
(Zea mays)
Liliopsida Zm.3261 33
sea squirt
(Ciona savignyi)
Ascidiacea -- 34
  • 63 (a)
bread mold
(Neurospora crassa)
Ascomycetes NCU02639 33
  • 60.5 (n)
fission yeast
(Schizosaccharomyces pombe)
Schizosaccharomycetes arg12 33
  • 55.95 (n)
sea squirt
(Ciona intestinalis)
Ascidiacea Cin.2241 33
Species where no ortholog for ASS1 was found in the sources mined by GeneCards:
  • Actinobacteria (Mycobacterium tuberculosis)
  • Alicante grape (Vitis vinifera)
  • alpha proteobacteria (Wolbachia pipientis)
  • amoeba (Dictyostelium discoideum)
  • Archea (Pyrococcus horikoshii)
  • barley (Hordeum vulgare)
  • beta proteobacteria (Neisseria meningitidis)
  • Chromalveolata (Phytophthora infestans)
  • common water flea (Daphnia pulex)
  • E. coli (Escherichia coli)
  • filamentous fungi (Aspergillus nidulans)
  • Firmicute bacteria (Streptococcus pneumoniae)
  • green algae (Chlamydomonas reinhardtii)
  • honey bee (Apis mellifera)
  • lizard (Anolis carolinensis)
  • loblloly pine (Pinus taeda)
  • malaria parasite (Plasmodium falciparum)
  • medicago trunc (Medicago Truncatula)
  • moss (Physcomitrella patens)
  • orangutan (Pongo pygmaeus)
  • pig (Sus scrofa)
  • rice blast fungus (Magnaporthe grisea)
  • schistosome parasite (Schistosoma mansoni)
  • sea anemone (Nematostella vectensis)
  • sea urchin (Strongylocentrotus purpuratus)
  • sorghum (Sorghum bicolor)
  • soybean (Glycine max)
  • stem rust fungus (Puccinia graminis)
  • sugarcane (Saccharum officinarum)
  • tomato (Lycopersicon esculentum)
  • toxoplasmosis (Toxoplasma gondii)
  • Trichoplax (Trichoplax adhaerens)
  • worm (Caenorhabditis elegans)

Evolution for ASS1 Gene

Gene Tree for ASS1 (if available)
Gene Tree for ASS1 (if available)

Paralogs for ASS1 Gene

No data available for Paralogs for ASS1 Gene

Variants for ASS1 Gene

Sequence variations from dbSNP and Humsavar for ASS1 Gene

SNP ID Clin Chr 09 pos Sequence Context AA Info Type
rs121908636 Pathogenic, Citrullinemia 1 (CTLN1) [MIM:215700] 130,452,268(+) GTGGC(A/G)GCCTG reference, missense
rs121908637 Pathogenic, Citrullinemia 1 (CTLN1) [MIM:215700] 130,466,774(+) GGGCC(A/G)CAATG reference, missense
rs121908638 Pathogenic, Citrullinemia 1 (CTLN1) [MIM:215700] 130,470,877(+) GTGGA(A/G)CATGG reference, missense
rs121908639 other, Citrullinemia 1 (CTLN1) [MIM:215700] 130,489,464(+) ATACC(A/G)GTGCG reference, missense
rs121908640 Pathogenic, Citrullinemia 1 (CTLN1) [MIM:215700] 130,494,983(+) TCGGC(C/T)GGGAG intron-variant, reference, missense

Structural Variations from Database of Genomic Variants (DGV) for ASS1 Gene

Variant ID Type Subtype PubMed ID
nsv982349 CNV duplication 23825009
nsv982348 CNV duplication 23825009
nsv972456 CNV duplication 23825009
nsv972455 CNV duplication 23825009
nsv831734 CNV gain 17160897
nsv6734 CNV deletion 18451855
nsv615524 CNV loss 21841781
nsv615523 CNV loss 21841781
nsv466600 CNV loss 19166990
nsv466597 CNV loss 19166990
nsv1051541 CNV gain 25217958
esv1002962 CNV deletion 20482838
dgv7718n100 CNV gain 25217958
dgv12911n54 CNV loss 21841781

Variation tolerance for ASS1 Gene

Residual Variation Intolerance Score: 27.4% of all genes are more intolerant (likely to be disease-causing)
Gene Damage Index Score: 2.64; 45.53% of all genes are more intolerant (likely to be disease-causing)

Relevant External Links for ASS1 Gene

Human Gene Mutation Database (HGMD)
SNPedia medical, phenotypic, and genealogical associations of SNPs for

No data available for Polymorphic Variants from UniProtKB/Swiss-Prot for ASS1 Gene

Disorders for ASS1 Gene

MalaCards: The human disease database

(21) MalaCards diseases for ASS1 Gene - From: HGMD, OMIM, ClinVar, GeneTests, Orphanet, Swiss-Prot, DISEASES, Novoseek, and GeneCards

Disorder Aliases PubMed IDs
  • ass deficiency
acute neonatal citrullinemia type i
  • acute neonatal citrullinemia type 1
adult-onset citrullinemia type i
  • adult-onset citrullinemia type 1
argininosuccinic aciduria
  • citrullinemia
lysinuric protein intolerance
  • dibasic amino aciduria ii
- elite association - COSMIC cancer census association via MalaCards
Search ASS1 in MalaCards View complete list of genes associated with diseases


  • Citrullinemia 1 (CTLN1) [MIM:215700]: The classic form of citrullinemia, an autosomal recessive disease characterized primarily by elevated serum and urine citrulline levels. Ammonia intoxication is another manifestation. It is a disorder of the urea cycle, usually manifesting in the first few days of life. Affected infants appear normal at birth, but as ammonia builds up in the body they present symptoms such as lethargy, poor feeding, vomiting, seizures and loss of consciousness. Less commonly, a milder form can develop later in childhood or adulthood. {ECO:0000269 PubMed:11708871, ECO:0000269 PubMed:11941481, ECO:0000269 PubMed:12815590, ECO:0000269 PubMed:14680976, ECO:0000269 PubMed:15863597, ECO:0000269 PubMed:16475226, ECO:0000269 PubMed:18473344, ECO:0000269 PubMed:19006241, ECO:0000269 PubMed:1943692, ECO:0000269 PubMed:2358466, ECO:0000269 PubMed:23611581, ECO:0000269 PubMed:24889030, ECO:0000269 PubMed:25179242, ECO:0000269 PubMed:27287393, ECO:0000269 PubMed:28111830, ECO:0000269 PubMed:7977368}. Note=The disease is caused by mutations affecting the gene represented in this entry.

Relevant External Links for ASS1

Genetic Association Database (GAD)
Human Genome Epidemiology (HuGE) Navigator
Atlas of Genetics and Cytogenetics in Oncology and Haematology:
genes like me logo Genes that share disorders with ASS1: view

No data available for Genatlas for ASS1 Gene

Publications for ASS1 Gene

  1. Mutations and polymorphisms in the human argininosuccinate synthetase (ASS1) gene. (PMID: 19006241) Engel K … Häberle J (Human mutation 2009) 3 4 22 60
  2. Investigation of citrullinemia type I variants by in vitro expression studies. (PMID: 18473344) Berning C … Häberle J (Human mutation 2008) 3 4 22 60
  3. Identification of 16 novel mutations in the argininosuccinate synthetase gene and genotype-phenotype correlation in 38 classical citrullinemia patients. (PMID: 12815590) Gao HZ … Saheki T (Human mutation 2003) 3 4 22 60
  4. Structure of the human argininosuccinate synthetase gene and an improved system for molecular diagnostics in patients with classical and mild citrullinemia. (PMID: 11941481) Häberle J … Koch HG (Human genetics 2002) 3 4 22 60
  5. Characterization of human wild-type and mutant argininosuccinate synthetase proteins expressed in bacterial cells. (PMID: 8792870) Shaheen N … Saheki T (Enzyme & protein 1994) 3 4 22 60

Products for ASS1 Gene

Sources for ASS1 Gene

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