PAICS

Existing Annotations Review

GO Term	Evidence	Action	Reason
GO:0004639 phosphoribosylaminoimidazolesuccinocarboxamide synthase activity	IBA GO_REF:0000033	ACCEPT	Summary: SAICAR synthetase (EC 6.3.2.6) is one of the two catalytic activities of this bifunctional enzyme and is a core molecular function. The phylogenetic (IBA) inference is fully consistent with direct experimental and structural evidence. Reason: Core enzymatic function directly supported by biochemistry and crystallography (PMID:17224163) and by the disease study (PMID:31600779). The IBA is at the correct level of specificity for this well-conserved family. Supporting Evidence: PMID:17224163 Phosphoribosylaminoimidazole carboxylase/phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS) is an important bifunctional enzyme in de novo purine biosynthesis in vertebrate with both 5-aminoimidazole ribonucleotide carboxylase (AIRc) and 4-(N-succinylcarboxamide)-5-aminoimidazole ribonucleotide synthetase (SAICARs) activities.
GO:0005829 cytosol	IBA GO_REF:0000033	ACCEPT	Summary: PAICS is a soluble cytosolic enzyme that acts in the cytoplasm as part of the de novo purine synthesis pathway and the purinosome. The IBA localization is corroborated by Reactome TAS annotations to cytosol. Reason: Correct site of action for this cytosolic metabolic enzyme, consistent with purinosome biology (PMID:31600779) and independent Reactome curation. Supporting Evidence: PMID:31600779 Similar to other two known DNPS defects-adenylosuccinate lyase deficiency and AICA-ribosiduria-the PAICS mutation prevented purinosome formation in the patient's skin fibroblasts, and this phenotype was corrected by
GO:0006189 'de novo' IMP biosynthetic process	IBA GO_REF:0000033	ACCEPT	Summary: PAICS catalyzes two consecutive steps of the ten-reaction de novo pathway that builds IMP, making 'de novo' IMP biosynthetic process the correct core biological process. Reason: Correct pathway assignment for both catalytic activities; the IBA inference matches direct experimental evidence (PMID:27590927, PMID:31600779) and UniProt pathway annotation. Supporting Evidence: PMID:27590927 DNPS includes ten reactions catalysed by six enzymes.
GO:0004638 phosphoribosylaminoimidazole carboxylase activity	IEA GO_REF:0000120	ACCEPT	Summary: AIR carboxylase (EC 4.1.1.21) is one of the two core catalytic activities. This IEA (RHEA/EC mapping) is correct and redundant with the experimental EXP/IDA/IMP annotations for the same term. Reason: Accurate EC/RHEA-based mapping to a directly demonstrated enzymatic activity (PMID:17224163). Supporting Evidence: PMID:17224163 Phosphoribosylaminoimidazole carboxylase/phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS) is an important bifunctional enzyme in de novo purine biosynthesis in vertebrate with both 5-aminoimidazole ribonucleotide carboxylase (AIRc) and 4-(N-succinylcarboxamide)-5-aminoimidazole ribonucleotide synthetase (SAICARs) activities.
GO:0004639 phosphoribosylaminoimidazolesuccinocarboxamide synthase activity	IEA GO_REF:0000120	ACCEPT	Summary: SAICAR synthetase (EC 6.3.2.6) core catalytic activity; IEA EC/RHEA mapping is correct and redundant with the experimental annotations for the same term. Reason: Accurate EC/RHEA-based mapping to a directly demonstrated enzymatic activity (PMID:17224163). Supporting Evidence: PMID:17224163 Phosphoribosylaminoimidazole carboxylase/phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS) is an important bifunctional enzyme in de novo purine biosynthesis in vertebrate with both 5-aminoimidazole ribonucleotide carboxylase (AIRc) and 4-(N-succinylcarboxamide)-5-aminoimidazole ribonucleotide synthetase (SAICARs) activities.
GO:0006164 purine nucleotide biosynthetic process	IEA GO_REF:0000002	ACCEPT	Summary: Correct but general parent process. PAICS acts in de novo purine nucleotide biosynthesis; the more specific 'de novo' IMP biosynthetic process (GO:0006189) is also annotated and better captures the enzyme's role. Reason: Biologically accurate broad process term from InterPro2GO; kept because IEAs may legitimately be broader than the more specific experimental terms. Not marked core because the more specific GO:0006189 is the core process. Supporting Evidence: PMID:31600779 We report for the first time an autosomal recessive inborn error of de novo
GO:0006189 'de novo' IMP biosynthetic process	IEA GO_REF:0000120	ACCEPT	Summary: Correct core biological process, redundant with the IBA and experimental annotations to the same term. Reason: Accurate UniPathway/InterPro-based mapping to the de novo IMP biosynthesis pathway in which PAICS acts. Supporting Evidence: PMID:27590927 DNPS includes ten reactions catalysed by six enzymes.
GO:0005515 protein binding	IPI PMID:16189514 Towards a proteome-scale map of the human protein-protein in...	MARK AS OVER ANNOTATED	Summary: Generic protein-binding annotation from a large-scale interactome dataset. Uninformative about molecular function and does not represent a core function. Reason: Bare 'protein binding' conveys no specific molecular function and derives from high-throughput interactome screening. Per curation guidelines this term should be avoided in favor of informative MF terms; retained per policy (do not remove IPIs) but flagged as over-annotated.
GO:0005515 protein binding	IPI PMID:19060904 An empirical framework for binary interactome mapping.	MARK AS OVER ANNOTATED	Summary: Generic protein-binding annotation from a binary interactome mapping study; uninformative about molecular function. Reason: Bare 'protein binding' from a high-throughput binary interactome dataset does not describe a specific molecular function; over-annotated.
GO:0005515 protein binding	IPI PMID:21653829 Protein interactome reveals converging molecular pathways am...	MARK AS OVER ANNOTATED	Summary: Generic protein-binding annotation from an autism-focused interactome study; uninformative about molecular function. Reason: Bare 'protein binding' from high-throughput interactome data; not an informative molecular function and not core.
GO:0005515 protein binding	IPI PMID:25416956 A proteome-scale map of the human interactome network.	MARK AS OVER ANNOTATED	Summary: Generic protein-binding annotation from a proteome-scale interactome map; uninformative about molecular function. Reason: Bare 'protein binding' from a high-throughput interactome dataset; over-annotated.
GO:0005515 protein binding	IPI PMID:26871637 Widespread Expansion of Protein Interaction Capabilities by ...	MARK AS OVER ANNOTATED	Summary: Generic protein-binding annotation from an alternative-splicing interactome study; uninformative about molecular function. Reason: Bare 'protein binding' from high-throughput interactome mapping; not informative and not core.
GO:0005515 protein binding	IPI PMID:32296183 A reference map of the human binary protein interactome.	MARK AS OVER ANNOTATED	Summary: Generic protein-binding annotation from a reference binary interactome map; uninformative about molecular function. Reason: Bare 'protein binding' from a high-throughput binary interactome dataset; over-annotated.
GO:0042802 identical protein binding	IPI PMID:16169070 A human protein-protein interaction network: a resource for ...	KEEP AS NON CORE	Summary: Self-association is biologically real for PAICS, which forms a homooctamer. However, this is a structural/oligomerization property rather than a core enzymatic function, and the supporting datasets are high-throughput interactome screens. Reason: PAICS is a homooctamer (PMID:17224163), so identical-protein-binding is genuine and the octameric quaternary structure is functionally important for the carboxylase active sites. Kept as a valid but non-core annotation (self-assembly rather than catalytic function). The IPI evidence itself comes from a Y2H interactome screen. Supporting Evidence: PMID:17224163 eight PAICS subunits, each composed of distinct AIRc and SAICARs domains, assemble a compact homo-octamer with an octameric-carboxylase core and four symmetric periphery dimers formed by synthetase domains PMID:16169070 a protein matrix of 4456 baits and 5632 preys was screened by automated yeast two-hybrid (Y2H) interaction mating
GO:0042802 identical protein binding	IPI PMID:16189514 Towards a proteome-scale map of the human protein-protein in...	KEEP AS NON CORE	Summary: Self-association consistent with the homooctamer; valid but non-core (structural oligomerization rather than catalytic function). Reason: Corroborated by the crystal structure showing a homooctamer (PMID:17224163); retained as a genuine but non-core property. Supporting Evidence: PMID:17224163 eight PAICS subunits, each composed of distinct AIRc and SAICARs domains, assemble a compact homo-octamer with an octameric-carboxylase core and four symmetric periphery dimers formed by synthetase domains
GO:0042802 identical protein binding	IPI PMID:21988832 Toward an understanding of the protein interaction network o...	KEEP AS NON CORE	Summary: Self-association consistent with the homooctamer; valid but non-core. Reason: PAICS homooctamerization is documented structurally (PMID:17224163); retained as a real but non-core oligomerization property. Supporting Evidence: PMID:17224163 eight PAICS subunits, each composed of distinct AIRc and SAICARs domains, assemble a compact homo-octamer with an octameric-carboxylase core and four symmetric periphery dimers formed by synthetase domains
GO:0042802 identical protein binding	IPI PMID:25416956 A proteome-scale map of the human interactome network.	KEEP AS NON CORE	Summary: Self-association consistent with the homooctamer; valid but non-core. Reason: Consistent with the octameric quaternary structure (PMID:17224163); retained as a genuine but non-core property. Supporting Evidence: PMID:17224163 eight PAICS subunits, each composed of distinct AIRc and SAICARs domains, assemble a compact homo-octamer with an octameric-carboxylase core and four symmetric periphery dimers formed by synthetase domains
GO:0042802 identical protein binding	IPI PMID:32296183 A reference map of the human binary protein interactome.	KEEP AS NON CORE	Summary: Self-association consistent with the homooctamer; valid but non-core. Reason: Consistent with the homooctamer (PMID:17224163); retained as a real but non-core oligomerization property. Supporting Evidence: PMID:17224163 eight PAICS subunits, each composed of distinct AIRc and SAICARs domains, assemble a compact homo-octamer with an octameric-carboxylase core and four symmetric periphery dimers formed by synthetase domains
GO:0004638 phosphoribosylaminoimidazole carboxylase activity	EXP PMID:17224163 Octameric structure of the human bifunctional enzyme PAICS i...	ACCEPT	Summary: AIR carboxylase (EC 4.1.1.21) core catalytic activity, directly demonstrated by biochemistry, crystallography (PDB 2H31) and active-site mutagenesis (His-303, Ser-332, Gly-334 loss-of-function). Reason: Directly experimentally supported core molecular function; the structural study identified the carboxylase active site and confirmed catalytic activity. Supporting Evidence: PMID:17224163 Phosphoribosylaminoimidazole carboxylase/phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS) is an important bifunctional enzyme in de novo purine biosynthesis in vertebrate with both 5-aminoimidazole ribonucleotide carboxylase (AIRc) and 4-(N-succinylcarboxamide)-5-aminoimidazole ribonucleotide synthetase (SAICARs) activities.
GO:0004639 phosphoribosylaminoimidazolesuccinocarboxamide synthase activity	EXP PMID:17224163 Octameric structure of the human bifunctional enzyme PAICS i...	ACCEPT	Summary: SAICAR synthetase (EC 6.3.2.6) core catalytic activity, directly demonstrated by biochemistry and crystallography. Reason: Directly experimentally supported core molecular function. Supporting Evidence: PMID:17224163 Phosphoribosylaminoimidazole carboxylase/phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS) is an important bifunctional enzyme in de novo purine biosynthesis in vertebrate with both 5-aminoimidazole ribonucleotide carboxylase (AIRc) and 4-(N-succinylcarboxamide)-5-aminoimidazole ribonucleotide synthetase (SAICARs) activities.
GO:0004638 phosphoribosylaminoimidazole carboxylase activity	IMP PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	ACCEPT	Summary: CRISPR-Cas9 knockout of PAICS in HeLa cells caused accumulation of its substrate, confirming the AIR carboxylase activity in vivo. Core molecular function. Reason: In vivo genetic (IMP) evidence via substrate accumulation upon knockout; supports the core carboxylase activity. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0006177 GMP biosynthetic process	IMP PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	KEEP AS NON CORE	Summary: PAICS acts upstream of IMP, which is the branch-point precursor for both AMP and GMP synthesis. GMP biosynthesis is therefore a downstream consequence, captured appropriately with the acts_upstream_of_or_within qualifier, but it is not PAICS's direct pathway step. Reason: Correct but downstream and indirect; PAICS makes an IMP precursor and GMP synthesis occurs downstream of IMP. The acts_upstream_of_or_within qualifier is appropriate. Not a core process for PAICS, whose direct role is IMP biosynthesis. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0006189 'de novo' IMP biosynthetic process	IMP PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	ACCEPT	Summary: Core biological process. PAICS knockout with substrate accumulation confirms its role in de novo IMP biosynthesis. Reason: Direct genetic evidence for the core pathway; the direct role of PAICS is in de novo IMP biosynthesis. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0044208 'de novo' AMP biosynthetic process	IMP PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	KEEP AS NON CORE	Summary: AMP biosynthesis occurs downstream of IMP; PAICS contributes indirectly by producing the IMP precursor. Appropriately captured with acts_upstream_of_or_within, but not PAICS's direct step. Reason: Correct but downstream and indirect; PAICS's direct role is IMP biosynthesis and AMP is made from IMP. Retained as non-core with the upstream qualifier. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0097294 'de novo' XMP biosynthetic process	IMP PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	KEEP AS NON CORE	Summary: XMP biosynthesis is downstream of IMP (IMP to XMP to GMP); PAICS contributes indirectly via the IMP precursor. Appropriately captured with acts_upstream_of_or_within, but not PAICS's direct step. Reason: Correct but downstream and indirect; PAICS's direct role is de novo IMP biosynthesis. Retained as non-core with the upstream qualifier. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0004638 phosphoribosylaminoimidazole carboxylase activity	IMP PMID:31600779 PAICS deficiency, a new defect of de novo purine synthesis r...	ACCEPT	Summary: The disease mutation p.Lys53Arg reduced both catalytic activities of PAICS, providing genetic evidence for the AIR carboxylase (EC 4.1.1.21) activity. Core molecular function. Reason: Genetic (IMP) evidence from a human loss-of-function disease variant that reduced the carboxylase activity; core enzymatic function. Supporting Evidence: PMID:31600779 The mutation reduced the catalytic activity of PAICS in heterozygous carrier and patient skin fibroblasts to approximately 50 and 10% of control levels, respectively.
GO:0004639 phosphoribosylaminoimidazolesuccinocarboxamide synthase activity	IMP PMID:31600779 PAICS deficiency, a new defect of de novo purine synthesis r...	ACCEPT	Summary: The disease mutation reduced both catalytic activities, providing genetic evidence for the SAICAR synthetase (EC 6.3.2.6) activity. Core molecular function. Reason: Genetic (IMP) evidence from a human loss-of-function disease variant affecting the bifunctional enzyme's catalytic activity; core enzymatic function. Supporting Evidence: PMID:31600779 that affects the structure of the catalytic site of the bifunctional enzyme phosphoribosylaminoimidazole
GO:0009113 purine nucleobase biosynthetic process	IDA PMID:31600779 PAICS deficiency, a new defect of de novo purine synthesis r...	KEEP AS NON CORE	Summary: PAICS participates in de novo purine synthesis, which ultimately produces purine nucleotides. This is a broadly correct process term; the more specific 'de novo' IMP biosynthetic process better captures the direct role. Reason: Correct but general. The core process term for PAICS is 'de novo' IMP biosynthetic process (GO:0006189); this broader purine nucleobase term is retained as non-core. Supporting Evidence: PMID:31600779 We report for the first time an autosomal recessive inborn error of de novo
GO:0097294 'de novo' XMP biosynthetic process	IDA PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	KEEP AS NON CORE	Summary: XMP biosynthesis is downstream of the IMP that PAICS helps produce. PAICS does not itself act in XMP synthesis, so this is a downstream/indirect involvement. Reason: PAICS's direct catalytic role is in de novo IMP biosynthesis; XMP is made downstream (IMP to XMP). Retained as a genuine but non-core downstream association. Action kept consistent with the acts_upstream_of_or_within annotation to the same term. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0004638 phosphoribosylaminoimidazole carboxylase activity	IDA PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	ACCEPT	Summary: AIR carboxylase core catalytic activity, supported by direct assay of the recombinant enzyme and substrate accumulation on knockout. Reason: Directly experimentally supported core molecular function (recombinant enzyme prepared and characterized; substrate accumulates when the gene is knocked out). Supporting Evidence: PMID:27590927 we prepared specific recombinant DNPS enzymes
GO:0006177 GMP biosynthetic process	IDA PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	KEEP AS NON CORE	Summary: GMP synthesis is downstream of the IMP branch point; PAICS acts upstream of IMP and does not itself catalyze a GMP-synthesis step. Reason: PAICS's direct pathway step is de novo IMP biosynthesis; GMP is synthesized downstream of IMP. Retained as a genuine but non-core downstream association. Action kept consistent with the acts_upstream_of_or_within annotation to the same term. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0006189 'de novo' IMP biosynthetic process	IDA PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	ACCEPT	Summary: Core biological process directly supported; PAICS is a de novo purine synthesis enzyme whose knockout causes substrate accumulation within the pathway. Reason: Direct experimental support for the core pathway in which PAICS acts. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0004639 phosphoribosylaminoimidazolesuccinocarboxamide synthase activity	IDA PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	ACCEPT	Summary: SAICAR synthetase core catalytic activity, supported by direct assay of the recombinant enzyme and substrate accumulation on knockout. Reason: Directly experimentally supported core molecular function. Supporting Evidence: PMID:27590927 we prepared specific recombinant DNPS enzymes
GO:0044208 'de novo' AMP biosynthetic process	IDA PMID:27590927 CRISPR-Cas9 induced mutations along de novo purine synthesis...	KEEP AS NON CORE	Summary: AMP synthesis is downstream of the IMP that PAICS helps make. PAICS does not itself catalyze an AMP-synthesis step, so this is a downstream/indirect involvement. Reason: PAICS's direct pathway step is de novo IMP biosynthesis; AMP is made downstream of IMP. Retained as a genuine but non-core downstream association. Action kept consistent with the acts_upstream_of_or_within annotation to the same term. Supporting Evidence: PMID:27590927 an accumulation of the substrate(s) for the knocked out enzyme was identified
GO:0045296 cadherin binding	HDA PMID:25468996 E-cadherin interactome complexity and robustness resolved by...	MARK AS OVER ANNOTATED	Summary: This annotation derives from a BioID proximity-biotinylation screen of the E-cadherin cytoplasmic tail, in which PAICS was one of ~561 vicinal proteins. It reflects spatial proximity in a high-throughput screen, not a genuine cadherin-binding molecular function of this cytosolic metabolic enzyme. Reason: The source study identified hundreds of proximal proteins by promiscuous biotin ligase labeling; the authors themselves note many proximal proteins do not localize to junctions. PAICS is a cytosolic purine-synthesis enzyme with no evidence of a true cadherin-binding function. Over-annotation. Supporting Evidence: PMID:25468996 We used proximity biotinylation and quantitative proteomics to identify 561 proteins in the vicinity of the cytoplasmic tail of E-cadherin.
GO:0005737 cytoplasm	IDA PMID:25468996 E-cadherin interactome complexity and robustness resolved by...	ACCEPT	Summary: Cytoplasmic localization is correct for this soluble cytosolic enzyme, though the more specific cytosol (GO:0005829) is also annotated and preferred. Reason: Consistent with PAICS being a cytosolic enzyme; a valid, if general, localization. The more specific cytosol annotation captures the same information. Supporting Evidence: PMID:25468996 We used proximity biotinylation and quantitative proteomics to identify 561 proteins in the vicinity of the cytoplasmic tail of E-cadherin.
GO:0070062 extracellular exosome	HDA PMID:23533145 In-depth proteomic analyses of exosomes isolated from expres...	MARK AS OVER ANNOTATED	Summary: Detection in a shotgun proteomic survey of urinary prostatic-secretion exosomes (~900 proteins) reflects the abundance of this cytosolic enzyme in bulk proteomes rather than a functional extracellular/exosomal localization. Reason: PAICS is an abundant cytosolic metabolic enzyme commonly detected as a co-purifying species in large exosome/proteome datasets; there is no evidence of a functional role in the extracellular exosome. Over-annotation from high-throughput mass spectrometry. Supporting Evidence: PMID:23533145 In pooled EPS-urine exosome samples, ~900 proteins were detected.
GO:0016020 membrane	HDA PMID:19946888 Defining the membrane proteome of NK cells.	MARK AS OVER ANNOTATED	Summary: Detection in an NK-cell membrane-proteome preparation (1843 proteins, ~40% predicted membrane) reflects co-isolation of an abundant soluble enzyme with membrane fractions, not integral/peripheral membrane localization. PAICS has no transmembrane domain or lipid anchor. Reason: The study itself notes many identified proteins are cellular-process proteins only transiently or non-specifically associated with membranes. PAICS is a cytosolic enzyme lacking membrane-targeting features. Over-annotation from a membrane-enriched proteome. Supporting Evidence: PMID:19946888 Mass spectrometric analysis identified 1843 proteins with high confidence scores.
GO:0070062 extracellular exosome	HDA PMID:20458337 MHC class II-associated proteins in B-cell exosomes and pote...	MARK AS OVER ANNOTATED	Summary: Detection in a B-cell exosome proteome (539 proteins) reflects the abundance of this cytosolic enzyme in bulk proteomes, not a functional exosomal localization. Reason: High-throughput exosome proteomics routinely detects abundant cytosolic enzymes; PAICS is not functionally an extracellular exosome protein. Over-annotation. Supporting Evidence: PMID:20458337 we first analyzed the total proteome of highly purified B cell-derived exosomes using sensitive and accurate mass spectrometry (MS), and identified 539 proteins
GO:0005829 cytosol	TAS Reactome:R-HSA-73805	ACCEPT	Summary: Cytosolic localization curated by Reactome for the SAICAR synthetase reaction (CAIR + Aspartate + ATP to SAICAR + ADP + Pi). Correct core localization. Reason: Authoritative pathway (Reactome) assignment consistent with all other evidence that PAICS is a cytosolic enzyme.
GO:0005829 cytosol	TAS Reactome:R-HSA-73806	ACCEPT	Summary: Cytosolic localization curated by Reactome for the AIR carboxylase reaction (AIR + CO2 to CAIR). Correct core localization. Reason: Authoritative pathway (Reactome) assignment consistent with all other evidence that PAICS is a cytosolic enzyme.
GO:0004639 phosphoribosylaminoimidazolesuccinocarboxamide synthase activity	TAS PMID:2253271 Cloning and sequencing of a human cDNA coding for a multifun...	ACCEPT	Summary: Original cloning of the human cDNA identified the SAICAR synthetase (EC 6.3.2.6) activity from sequence homology and yeast complementation. Core molecular function; TAS supported by the primary literature. Reason: Foundational evidence for the SAICAR synthetase activity; the 5' half of the cDNA is homologous to bacterial SAICAR synthetase and complements yeast ade1. Supporting Evidence: PMID:2253271 Its 5' half is homologous to Bacillus subtilis SAICAR synthetase PMID:2253271 pADE2H1 clones complement both ade1 and ade2 mutants of S. cerevisiae
GO:0009113 purine nucleobase biosynthetic process	TAS PMID:2253271 Cloning and sequencing of a human cDNA coding for a multifun...	KEEP AS NON CORE	Summary: The cloning study established PAICS as a de novo purine pathway enzyme. Broadly correct process; the more specific 'de novo' IMP biosynthetic process is preferred as core. Reason: Correct but general. The specific core process is 'de novo' IMP biosynthetic process (GO:0006189); retained as non-core. Supporting Evidence: PMID:2253271 coding for a multifunctional polypeptide of the purine pathway

Gene Description

Existing Annotations Review

Core Functions

Phosphoribosylaminoimidazole carboxylase (AIR carboxylase) activity; carboxylates AIR to CAIR (EC 4.1.1.21) as the first of two consecutive de novo purine synthesis steps catalyzed by PAICS.

Phosphoribosylaminoimidazolesuccinocarboxamide synthetase (SAICAR synthetase) activity; ATP-dependent condensation of CAIR with L-aspartate to form SAICAR (EC 6.3.2.6), the second consecutive de novo purine synthesis step catalyzed by PAICS.

References

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Notes

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