U.S. flag

An official website of the United States government

ALAD aminolevulinate dehydratase [ Homo sapiens (human) ]

Gene ID: 210, updated on 4-Jan-2025

Summary

Official Symbol
ALADprovided by HGNC
Official Full Name
aminolevulinate dehydrataseprovided by HGNC
Primary source
HGNC:HGNC:395
See related
Ensembl:ENSG00000148218 MIM:125270; AllianceGenome:HGNC:395
Gene type
protein coding
RefSeq status
REVIEWED
Organism
Homo sapiens
Lineage
Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi; Mammalia; Eutheria; Euarchontoglires; Primates; Haplorrhini; Catarrhini; Hominidae; Homo
Also known as
PBGS; ALADH
Summary
The ALAD enzyme is composed of 8 identical subunits and catalyzes the condensation of 2 molecules of delta-aminolevulinate to form porphobilinogen (a precursor of heme, cytochromes and other hemoproteins). ALAD catalyzes the second step in the porphyrin and heme biosynthetic pathway; zinc is essential for enzymatic activity. ALAD enzymatic activity is inhibited by lead and a defect in the ALAD structural gene can cause increased sensitivity to lead poisoning and acute hepatic porphyria. Alternative splicing of this gene results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Dec 2015]
Expression
Ubiquitous expression in adrenal (RPKM 60.0), liver (RPKM 56.7) and 25 other tissues See more
Orthologs
NEW
Try the new Gene table
Try the new Transcript table

Genomic context

See ALAD in Genome Data Viewer
Location:
9q32
Exon count:
15
Annotation release Status Assembly Chr Location
RS_2024_08 current GRCh38.p14 (GCF_000001405.40) 9 NC_000009.12 (113386312..113401284, complement)
RS_2024_08 current T2T-CHM13v2.0 (GCF_009914755.1) 9 NC_060933.1 (125585129..125600114, complement)
RS_2024_09 previous assembly GRCh37.p13 (GCF_000001405.25) 9 NC_000009.11 (116148592..116163564, complement)

Chromosome 9 - NC_000009.12Genomic Context describing neighboring genes Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 20199 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 20200 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 20201 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116131698-116132198 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116132199-116132699 Neighboring gene B-box and SPRY domain containing Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 20202 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28837 Neighboring gene haloacid dehalogenase like hydrolase domain containing 3 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr9:116162720-116163300 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 20203 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 20204 Neighboring gene CDK7 strongly-dependent group 2 enhancer GRCh37_chr9:116171753-116172952 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr9:116173655-116174554 Neighboring gene chromosome 9 open reading frame 43 Neighboring gene DNA polymerase epsilon 3, accessory subunit Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116224910-116225864 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116225865-116226819 Neighboring gene regulator of G protein signaling 3 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr9:116265604-116266246 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr9:116266247-116266887 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28840 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28841 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28842 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28843 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28844 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28845 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28846 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28847 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116286687-116287497 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr9:116298300-116299051 Neighboring gene H3K27ac hESC enhancer GRCh37_chr9:116303397-116303896 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116304621-116305136 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116305137-116305652 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116326740-116327461 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116327462-116328182 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28848 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28849 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 28850 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr9:116344249-116344757 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr9:116349073-116349850 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116351247-116351748 Neighboring gene H3K4me1 hESC enhancer GRCh37_chr9:116351749-116352248

Genomic regions, transcripts, and products

Expression

  • Project title: Tissue-specific circular RNA induction during human fetal development
  • Description: 35 human fetal samples from 6 tissues (3 - 7 replicates per tissue) collected between 10 and 20 weeks gestational time were sequenced using Illumina TruSeq Stranded Total RNA
  • BioProject: PRJNA270632
  • Publication: PMID 26076956
  • Analysis date: Mon Apr 2 22:54:59 2018

Bibliography

GeneRIFs: Gene References Into Functions

What's a GeneRIF?

Phenotypes

Associated conditions

Description Tests
Porphobilinogen synthase deficiency
MedGen: C0268328 OMIM: 612740 GeneReviews: Not available
Compare labs

Pathways from PubChem

Interactions

General gene information

Clone Names

  • MGC5057

Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables catalytic activity PubMed 
enables identical protein binding PubMed 
enables porphobilinogen synthase activity  
enables porphobilinogen synthase activity PubMed 
enables proteasome core complex binding  
enables zinc ion binding  
enables zinc ion binding PubMed 
Items 1 - 25 of 33
Process Evidence Code Pubs
involved_in cellular response to interleukin-4  
involved_in cellular response to lead ion  
involved_in heme A biosynthetic process  
involved_in heme B biosynthetic process  
involved_in heme O biosynthetic process  
involved_in heme biosynthetic process  
involved_in heme biosynthetic process PubMed 
involved_in negative regulation of proteasomal protein catabolic process PubMed 
involved_in protein homooligomerization PubMed 
involved_in protoporphyrinogen IX biosynthetic process  
involved_in response to activity  
involved_in response to aluminum ion  
involved_in response to amino acid  
involved_in response to arsenic-containing substance  
involved_in response to cadmium ion  
involved_in response to cobalt ion  
involved_in response to ethanol  
involved_in response to fatty acid  
involved_in response to glucocorticoid  
involved_in response to herbicide  
involved_in response to hypoxia  
involved_in response to ionizing radiation  
involved_in response to iron ion  
involved_in response to lipopolysaccharide  
involved_in response to mercury ion  
involved_in response to methylmercury  
involved_in response to oxidative stress  
involved_in response to platinum ion  
involved_in response to selenium ion  
involved_in response to vitamin B1  
involved_in response to vitamin E  
involved_in response to xenobiotic stimulus  
involved_in response to zinc ion  
Items 1 - 25 of 33
Component Evidence Code Pubs
is_active_in cytosol  
located_in cytosol  
located_in extracellular exosome PubMed 
located_in extracellular region  
located_in ficolin-1-rich granule lumen  
located_in nucleus PubMed 
located_in secretory granule lumen  

General protein information

Preferred Names
delta-aminolevulinic acid dehydratase
Names
aminolevulinate, delta-, dehydratase
porphobilinogen synthase
testicular tissue protein Li 95
NP_000022.3
NP_001003945.1
NP_001304674.1
XP_011516666.1
XP_047278900.1
XP_047278901.1
XP_047278902.1
XP_047278903.1
XP_054218281.1
XP_054218282.1
XP_054218283.1
XP_054218284.1

NCBI Reference Sequences (RefSeq)

NEW Try the new Transcript table

RefSeqs maintained independently of Annotated Genomes

These reference sequences exist independently of genome builds. Explain

These reference sequences are curated independently of the genome annotation cycle, so their versions may not match the RefSeq versions in the current genome build. Identify version mismatches by comparing the version of the RefSeq in this section to the one reported in Genomic regions, transcripts, and products above.

Genomic

  1. NG_008716.1 RefSeqGene

    Range
    5055..20027
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. NM_000031.6NP_000022.3  delta-aminolevulinic acid dehydratase isoform b

    See identical proteins and their annotated locations for NP_000022.3

    Status: REVIEWED

    Description
    Transcript Variant: This variant (2) lacks a segment of the coding region and initiates translation from an alternate start codon, compared to variant 1. The resulting isoform (b) has a distinct N-terminus, compared to isoform a.
    Source sequence(s)
    AK131490, AK290490, BC000977, BU625796, DA805310
    Consensus CDS
    CCDS6794.2
    UniProtKB/Swiss-Prot
    A8K375, B2R6F2, P13716, Q16870, Q16871, Q9BVQ9
    UniProtKB/TrEMBL
    A0A140VJL9, B7Z3I9
    Related
    ENSP00000386284.3, ENST00000409155.8
    Conserved Domains (1) summary
    cd04824
    Location:8327
    eu_ALAD_PBGS_cysteine_rich; Porphobilinogen synthase (PBGS), which is also called delta-aminolevulinic acid dehydratase (ALAD), catalyzes the condensation of two 5-aminolevulinic acid (ALA) molecules to form the pyrrole porphobilinogen (PBG), which is the second step in the ...
  2. NM_001003945.3NP_001003945.1  delta-aminolevulinic acid dehydratase isoform a

    Status: REVIEWED

    Description
    Transcript Variant: This variant (1) represents the longest transcript, and encodes the longest isoform (a).
    Source sequence(s)
    AK131490, AK290490, BU625796
    UniProtKB/TrEMBL
    Q6ZMU0
    Related
    ENST00000482847.5
    Conserved Domains (1) summary
    cd04824
    Location:68356
    eu_ALAD_PBGS_cysteine_rich; Porphobilinogen synthase (PBGS), which is also called delta-aminolevulinic acid dehydratase (ALAD), catalyzes the condensation of two 5-aminolevulinic acid (ALA) molecules to form the pyrrole porphobilinogen (PBG), which is the second step in the ...
  3. NM_001317745.2NP_001304674.1  delta-aminolevulinic acid dehydratase isoform c

    Status: REVIEWED

    Description
    Transcript Variant: This variant (3) differs in the 5' UTR, lacks an alternate in-frame exon in the 5' coding region and initiates translation from an alternate start codon, compared to variant 1. The resulting isoform (c) has a distinct N-terminus compared to isoform a.
    Source sequence(s)
    AK131490, AK295945, BU625796
    UniProtKB/TrEMBL
    B7Z3I9
    Conserved Domains (1) summary
    cd04824
    Location:17319
    eu_ALAD_PBGS_cysteine_rich; Porphobilinogen synthase (PBGS), which is also called delta-aminolevulinic acid dehydratase (ALAD), catalyzes the condensation of two 5-aminolevulinic acid (ALA) molecules to form the pyrrole porphobilinogen (PBG), which is the second step in the ...

RefSeqs of Annotated Genomes: GCF_000001405.40-RS_2024_08

The following sections contain reference sequences that belong to a specific genome build. Explain

Reference GRCh38.p14 Primary Assembly

Genomic

  1. NC_000009.12 Reference GRCh38.p14 Primary Assembly

    Range
    113386312..113401284 complement
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. XM_047422947.1XP_047278903.1  delta-aminolevulinic acid dehydratase isoform X4

    UniProtKB/TrEMBL
    B7Z3I9
  2. XM_011518364.3XP_011516666.1  delta-aminolevulinic acid dehydratase isoform X3

    See identical proteins and their annotated locations for XP_011516666.1

    UniProtKB/TrEMBL
    B7Z3I9
    Conserved Domains (1) summary
    cd04824
    Location:17336
    eu_ALAD_PBGS_cysteine_rich; Porphobilinogen synthase (PBGS), which is also called delta-aminolevulinic acid dehydratase (ALAD), catalyzes the condensation of two 5-aminolevulinic acid (ALA) molecules to form the pyrrole porphobilinogen (PBG), which is the second step in the ...
  3. XM_047422944.1XP_047278900.1  delta-aminolevulinic acid dehydratase isoform X1

    UniProtKB/TrEMBL
    B7Z3I9
  4. XM_047422945.1XP_047278901.1  delta-aminolevulinic acid dehydratase isoform X1

    UniProtKB/TrEMBL
    B7Z3I9
  5. XM_047422946.1XP_047278902.1  delta-aminolevulinic acid dehydratase isoform X2

    UniProtKB/TrEMBL
    Q6ZMU0

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060933.1 Alternate T2T-CHM13v2.0

    Range
    125585129..125600114 complement
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. XM_054362307.1XP_054218282.1  delta-aminolevulinic acid dehydratase isoform X1

    UniProtKB/TrEMBL
    B7Z3I9
  2. XM_054362309.1XP_054218284.1  delta-aminolevulinic acid dehydratase isoform X3

    UniProtKB/TrEMBL
    B7Z3I9
  3. XM_054362306.1XP_054218281.1  delta-aminolevulinic acid dehydratase isoform X1

    UniProtKB/TrEMBL
    B7Z3I9
  4. XM_054362308.1XP_054218283.1  delta-aminolevulinic acid dehydratase isoform X2

    UniProtKB/TrEMBL
    Q6ZMU0
External link. Please review our privacy policy.