Seroatlas · Human Serome Atlas

ALAS1

5-aminolevulinate synthase, non-specific, mitochondrial

Also known as: ALAS, ALAS-H, ALAS3, HEM1_HUMAN

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P13196
Gene
ALAS1
Ensembl
ENSG00000023330
Chromosome
3
Canonical length
640 aa
Protein class
Enzymes, Metabolic proteins, Plasma proteins, Predicted intracellular proteins
Subcellular location
Nucleoplasm,Mitochondria
Quaternary structure
Homodimer

OverviewNCBI Gene

This gene encodes the mitochondrial enzyme which is catalyzes the rate-limiting step in heme (iron-protoporphyrin) biosynthesis. The enzyme encoded by this gene is the housekeeping enzyme; a separate gene encodes a form of the enzyme that is specific for erythroid tissue. The level of the mature encoded protein is regulated by heme: high levels of heme down-regulate the mature enzyme in mitochondria while low heme levels up-regulate. A pseudogene of this gene is located on chromosome 12. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Jan 2015]

Canonical amino-acid sequenceUniProt

640 residues, UniProt reviewed canonical sequence.

>P13196|ALAS1
     1  MESVVRRCPF LSRVPQAFLQ KAGKSLLFYA QNCPKMMEVG AKPAPRALST AAVHYQQIKE
    61  TPPASEKDKT AKAKVQQTPD GSQQSPDGTQ LPSGHPLPAT SQGTASKCPF LAAQMNQRGS
   121  SVFCKASLEL QEDVQEMNAV RKEVAETSAG PSVVSVKTDG GDPSGLLKNF QDIMQKQRPE
   181  RVSHLLQDNL PKSVSTFQYD RFFEKKIDEK KNDHTYRVFK TVNRRAHIFP MADDYSDSLI
   241  TKKQVSVWCS NDYLGMSRHP RVCGAVMDTL KQHGAGAGGT RNISGTSKFH VDLERELADL
   301  HGKDAALLFS SCFVANDSTL FTLAKMMPGC EIYSDSGNHA SMIQGIRNSR VPKYIFRHND
   361  VSHLRELLQR SDPSVPKIVA FETVHSMDGA VCPLEELCDV AHEFGAITFV DEVHAVGLYG
   421  ARGGGIGDRD GVMPKMDIIS GTLGKAFGCV GGYIASTSSL IDTVRSYAAG FIFTTSLPPM
   481  LLAGALESVR ILKSAEGRVL RRQHQRNVKL MRQMLMDAGL PVVHCPSHII PVRVADAAKN
   541  TEVCDELMSR HNIYVQAINY PTVPRGEELL RIAPTPHHTP QMMNYFLENL LVTWKQVGLE
   601  LKPHSSAECN FCRRPLHFEV MSEREKSYFS GLSKLVSAQA

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against ALAS1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
0
Mean surface accessibility (rSASA)
0.34
Highest tissue expression
697 nTPM

Expression across tissuesHPA

Tissue

  • adrenal gland: 697 nTPM
  • liver: 513 nTPM
  • bone marrow: 167 nTPM
  • heart muscle: 110 nTPM
  • skeletal muscle: 104 nTPM
  • tongue: 100 nTPM

Single-cell type

  • adrenal cortex cells: 534 nCPM
  • syncytiotrophoblasts: 420 nCPM
  • hepatocytes: 282 nCPM
  • urothelial cells: 168 nCPM
  • esophageal apical cells: 140 nCPM
  • mast cells: 133 nCPM

Immune cell

  • basophil: 234 nTPM
  • eosinophil: 103 nTPM
  • neutrophil: 50 nTPM
  • intermediate monocyte: 43 nTPM
  • non-classical monocyte: 39 nTPM
  • MAIT T-cell: 38 nTPM

Brain region

  • cerebral cortex: 161 nTPM
  • cerebellum: 61 nTPM
  • choroid plexus: 57 nTPM
  • pons: 52 nTPM
  • thalamus: 50 nTPM
  • hypothalamus: 41 nTPM

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
0.49
gnomAD pLI
0.11
gnomAD missense Z
1.19
DepMap mean gene effect
-0.22
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 3% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

InteractionsUniProt · HPA

Protein binding partners of ALAS1 in the human serome: UniProt-annotated complex subunits plus reported interactors. Each links to its own Seroatlas record.

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads ALAS1 as an antibody target. Whether an autoantibody or antibody against ALAS1 could matter depends on whether native ALAS1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

ALAS1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label ALAS1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/ALAS1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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