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OXSM 3-oxoacyl-ACP synthase, mitochondrial [ Homo sapiens (human) ]

Gene ID: 54995, updated on 6-Jul-2025
Official Symbol
OXSMprovided by HGNC
Official Full Name
3-oxoacyl-ACP synthase, mitochondrialprovided by HGNC
Primary source
HGNC:HGNC:26063
See related
Ensembl:ENSG00000151093 MIM:610324; AllianceGenome:HGNC:26063
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
KS; CEM1; KASI; FASN2D
Summary
This gene encodes a beta-ketoacyl synthetase. The encoded enzyme is required for elongation of fatty acid chains in the mitochondria. Alternatively spliced transcript variants have been described.[provided by RefSeq, Feb 2009]
Expression
Ubiquitous expression in testis (RPKM 3.3), thyroid (RPKM 1.6) and 25 other tissues See more
Orthologs
mouse all
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See OXSM in Genome Data Viewer
Location:
3p24.2
Exon count:
3
Annotation release Status Assembly Chr Location
RS_2024_08 current GRCh38.p14 (GCF_000001405.40) 3 NC_000003.12 (25790090..25794531)
RS_2024_08 current T2T-CHM13v2.0 (GCF_009914755.1) 3 NC_060927.1 (25786612..25797297)
RS_2024_09 previous assembly GRCh37.p13 (GCF_000001405.25) 3 NC_000003.11 (25831581..25836022)

Chromosome 3 - NC_000003.12Genomic Context describing neighboring genes Neighboring gene N-glycanase 1 Neighboring gene NANOG hESC enhancer GRCh37_chr3:25793125-25793639 Neighboring gene ribosomal protein L32 pseudogene 11 Neighboring gene TATA-box binding protein associated factor 9b pseudogene 1 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 19609 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 19610 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 19611 Neighboring gene ATAC-STARR-seq lymphoblastoid silent region 14147 Neighboring gene H3K27ac-H3K4me1 hESC enhancer GRCh37_chr3:25831060-25831589 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 19612 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 19613 Neighboring gene uncharacterized LOC105377000 Neighboring gene ATAC-STARR-seq lymphoblastoid active region 19614 Neighboring gene BRD4-independent group 4 enhancer GRCh37_chr3:25893740-25894939 Neighboring gene NANOG hESC enhancer GRCh37_chr3:25900147-25901106 Neighboring gene long intergenic non-protein coding RNA 692

Go to nucleotide: Graphics FASTA GenBank

  • 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

Related articles in PubMed

  1. Knockdown of heat shock protein family D member 1 (HSPD1) promotes proliferation and migration of ovarian cancer cells via disrupting the stability of mitochondrial 3-oxoacyl-ACP synthase (OXSM). Duan Y, et al. J Ovarian Res, 2023 Apr 22. PMID 37087461, Free PMC Article
  2. Cloning, expression, and characterization of the human mitochondrial beta-ketoacyl synthase. Complementation of the yeast CEM1 knock-out strain. Zhang L, et al. J Biol Chem, 2005 Apr 1. PMID 15668256
  3. Variability in Streptavidin-Sepharose Matrix Quality Can Significantly Affect Proximity-Dependent Biotinylation (BioID) Data. St-Germain JR, et al. J Proteome Res, 2020 Aug 7. PMID 32628020
  4. New interaction partners for Nek4.1 and Nek4.2 isoforms: from the DNA damage response to RNA splicing. Basei FL, et al. Proteome Sci, 2015. PMID 25798074, Free PMC Article
  5. Systematic subcellular localization of novel proteins identified by large-scale cDNA sequencing. Simpson JC, et al. EMBO Rep, 2000 Sep. PMID 11256614, Free PMC Article

See all (27) citations in PubMed

GeneRIFs: Gene References Into Functions

What's a GeneRIF?
  1. Knockdown of heat shock protein family D member 1 (HSPD1) promotes proliferation and migration of ovarian cancer cells via disrupting the stability of mitochondrial 3-oxoacyl-ACP synthase (OXSM).
    Title: Knockdown of heat shock protein family D member 1 (HSPD1) promotes proliferation and migration of ovarian cancer cells via disrupting the stability of mitochondrial 3-oxoacyl-ACP synthase (OXSM).
  2. Observational study of gene-disease association. (HuGE Navigator)
    Title: Genetic variants in nuclear-encoded mitochondrial genes influence AIDS progression.
  3. characterization of the human mitochondrial beta-ketoacyl synthase
    Title: Cloning, expression, and characterization of the human mitochondrial beta-ketoacyl synthase. Complementation of the yeast CEM1 knock-out strain.
Submit: New GeneRIF Correction

Find tests for this gene in the NIH Genetic Testing Registry (GTR)

Review eQTL and phenotype association data in this region using PheGenI

See variants in ClinVar

See studies and variants in dbVar

See Variation Viewer (GRCh37.p13)

See Variation Viewer (GRCh38)

Products Interactant Other Gene Complex Source Pubs Description

Markers

Homology

Clone Names

  • FLJ20604

Gene Ontology Provided by GOA

Function Evidence Code Pubs
enables 3-oxoacyl-[acyl-carrier-protein] synthase activity IBA
Inferred from Biological aspect of Ancestor
more info
  
enables 3-oxoacyl-[acyl-carrier-protein] synthase activity IDA
Inferred from Direct Assay
more info
 PubMed 
enables 3-oxoacyl-[acyl-carrier-protein] synthase activity IEA
Inferred from Electronic Annotation
more info
  
enables acyltransferase activity IEA
Inferred from Electronic Annotation
more info
  
enables acyltransferase activity, transferring groups other than amino-acyl groups IEA
Inferred from Electronic Annotation
more info
  
enables transferase activity IEA
Inferred from Electronic Annotation
more info
  
Process Evidence Code Pubs
involved_in acyl-CoA metabolic process IDA
Inferred from Direct Assay
more info
 PubMed 
involved_in fatty acid biosynthetic process IBA
Inferred from Biological aspect of Ancestor
more info
  
involved_in fatty acid biosynthetic process IEA
Inferred from Electronic Annotation
more info
  
involved_in fatty acid metabolic process IEA
Inferred from Electronic Annotation
more info
  
involved_in lipid metabolic process IEA
Inferred from Electronic Annotation
more info
  
involved_in medium-chain fatty acid biosynthetic process IDA
Inferred from Direct Assay
more info
 PubMed 
involved_in short-chain fatty acid biosynthetic process IDA
Inferred from Direct Assay
more info
 PubMed 
Component Evidence Code Pubs
located_in cytosol IDA
Inferred from Direct Assay
more info
  
located_in mitochondrial matrix TAS
Traceable Author Statement
more info
  
located_in mitochondrion HTP PubMed 
is_active_in mitochondrion IBA
Inferred from Biological aspect of Ancestor
more info
  
located_in mitochondrion IDA
Inferred from Direct Assay
more info
  
located_in mitochondrion IEA
Inferred from Electronic Annotation
more info
  
located_in mitochondrion IMP
Inferred from Mutant Phenotype
more info
 PubMed 
Preferred Names
3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial
Names
3-ketoacyl-acyl carrier protein synthase
3-oxoacyl-acyl-carrier-protein synthase
acyl-malonyl acyl carrier protein-condensing enzyme
beta-ketoacyl synthase
beta-ketoacyl-ACP synthase
type II mitochondrial beta-ketoacyl synthase
NP_001138863.1
NP_060367.1
XP_006713279.1
XP_006713280.1
XP_054203004.1
XP_054203005.1
XP_054203006.1
XP_054203007.1

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.

mRNA and Protein(s)

  1. NM_001145391.2 → NP_001138863.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform 2 precursor

    Status: REVIEWED

    Description
    Transcript Variant: This variant (2) lacks an in-frame segment in the coding region compared to variant 1. Isoform 2 is shorter than isoform 1.
    Source sequence(s)
    AK225260, DA916187
    Consensus CDS
    CCDS46780.1
    UniProtKB/Swiss-Prot
    Q9NWU1
    Related
    ENSP00000411303.2, ENST00000420173.2
    Conserved Domains (1) summary
    cl09938
    Location:42 → 372
    cond_enzymes; Condensing enzymes; Family of enzymes that catalyze a (decarboxylating or non-decarboxylating) Claisen-like condensation reaction. Members are share strong structural similarity, and are involved in the synthesis and degradation of fatty acids, and the ...

  2. NM_017897.3 → NP_060367.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform 1 precursor

    See identical proteins and their annotated locations for NP_060367.1

    Status: REVIEWED

    Description
    Transcript Variant: This variant (1) represents the longest transcript and encodes the longer isoform (1).
    Source sequence(s)
    AK000611, DA916187
    Consensus CDS
    CCDS2643.1
    UniProtKB/Swiss-Prot
    Q9NWU1
    Related
    ENSP00000280701.3, ENST00000280701.8
    Conserved Domains (1) summary
    TIGR03150
    Location:42 → 455
    fabF; beta-ketoacyl-acyl-carrier-protein synthase II

RNA

  1. NR_026937.2 RNA Sequence

    Status: REVIEWED

    Description
    Transcript Variant: This variant (3) uses an alternate splice site in an internal exon, compared to variant 1. This variant is represented as non-coding because the use of the 5'-most supported translational start codon, as used in variant 1, renders the transcript a candidate for nonsense-mediated mRNA decay (NMD).
    Source sequence(s)
    AK000611, AK304821
    Related
    ENST00000448177.1

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_000003.12 Reference GRCh38.p14 Primary Assembly

    Range
    25790090..25794531
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. XM_006713216.5 → XP_006713279.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform X1

    See identical proteins and their annotated locations for XP_006713279.1

    UniProtKB/Swiss-Prot
    Q9NWU1
    Conserved Domains (1) summary
    TIGR03150
    Location:42 → 455
    fabF; beta-ketoacyl-acyl-carrier-protein synthase II

  2. XM_006713217.5 → XP_006713280.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform X2

    See identical proteins and their annotated locations for XP_006713280.1

    UniProtKB/TrEMBL
    B4E3Q7
    Conserved Domains (1) summary
    cd00834
    Location:1 → 181
    KAS_I_II; Beta-ketoacyl-acyl carrier protein (ACP) synthase (KAS), type I and II. KASs are responsible for the elongation steps in fatty acid biosynthesis. KASIII catalyses the initial condensation and KAS I and II catalyze further elongation steps by Claisen ...

Alternate T2T-CHM13v2.0

Genomic

  1. NC_060927.1 Alternate T2T-CHM13v2.0

    Range
    25786612..25797297
    Download
    GenBank, FASTA, Sequence Viewer (Graphics)

mRNA and Protein(s)

  1. XM_054347030.1 → XP_054203005.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform X1

    UniProtKB/Swiss-Prot
    Q9NWU1

  2. XM_054347029.1 → XP_054203004.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform X1

    UniProtKB/Swiss-Prot
    Q9NWU1

  3. XM_054347031.1 → XP_054203006.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform X2

    UniProtKB/TrEMBL
    B4E3Q7

  4. XM_054347032.1 → XP_054203007.1  3-oxoacyl-[acyl-carrier-protein] synthase, mitochondrial isoform X2

    UniProtKB/TrEMBL
    B4E3Q7
Nucleotide Protein
Heading Accession and Version
Protein Accession Links
GenPept Link UniProtKB Link
Q9NWU1.1 GenPept UniProtKB/Swiss-Prot:Q9NWU1

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