MPO

Protein identityUniProt · HPA

UniProt accession

P05164

Gene

MPO

Ensembl

ENSG00000005381

Chromosome

17

Canonical length

745 aa

Protein class

Cancer-related genes, Candidate cardiovascular disease genes, Disease related genes, Enzymes, Human disease related genes, Metabolic proteins, Plasma proteins, Potential drug targets, Predicted intracellular proteins

Subcellular location

Nucleoplasm,Vesicles

Secretome location

Intracellular and membrane

Quaternary structure

Homodimer

OverviewNCBI Gene

Myeloperoxidase (MPO) is a heme protein synthesized during myeloid differentiation that constitutes the major component of neutrophil azurophilic granules. Produced as a single chain precursor, myeloperoxidase is subsequently cleaved into a light and heavy chain. The mature myeloperoxidase is a tetramer composed of 2 light chains and 2 heavy chains. This enzyme produces hypohalous acids central to the microbicidal activity of neutrophils. [provided by RefSeq, Nov 2014]

Canonical amino-acid sequenceUniProt

745 residues, UniProt reviewed canonical sequence.

>P05164|MPO
     1  MGVPFFSSLR CMVDLGPCWA GGLTAEMKLL LALAGLLAIL ATPQPSEGAA PAVLGEVDTS
    61  LVLSSMEEAK QLVDKAYKER RESIKQRLRS GSASPMELLS YFKQPVAATR TAVRAADYLH
   121  VALDLLERKL RSLWRRPFNV TDVLTPAQLN VLSKSSGCAY QDVGVTCPEQ DKYRTITGMC
   181  NNRRSPTLGA SNRAFVRWLP AEYEDGFSLP YGWTPGVKRN GFPVALARAV SNEIVRFPTD
   241  QLTPDQERSL MFMQWGQLLD HDLDFTPEPA ARASFVTGVN CETSCVQQPP CFPLKIPPND
   301  PRIKNQADCI PFFRSCPACP GSNITIRNQI NALTSFVDAS MVYGSEEPLA RNLRNMSNQL
   361  GLLAVNQRFQ DNGRALLPFD NLHDDPCLLT NRSARIPCFL AGDTRSSEMP ELTSMHTLLL
   421  REHNRLATEL KSLNPRWDGE RLYQEARKIV GAMVQIITYR DYLPLVLGPT AMRKYLPTYR
   481  SYNDSVDPRI ANVFTNAFRY GHTLIQPFMF RLDNRYQPME PNPRVPLSRV FFASWRVVLE
   541  GGIDPILRGL MATPAKLNRQ NQIAVDEIRE RLFEQVMRIG LDLPALNMQR SRDHGLPGYN
   601  AWRRFCGLPQ PETVGQLGTV LRNLKLARKL MEQYGTPNNI DIWMGGVSEP LKRKGRVGPL
   661  LACIIGTQFR KLRDGDRFWW ENEGVFSMQQ RQALAQISLP RIICDNTGIT TVSKNNIFMS
   721  NSYPRDFVNC STLPALNLAS WREAS

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against MPO 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

Intracellular

Secreted

No

Transmembrane segments

0

Mean surface accessibility (rSASA)

0.23

Highest tissue expression

3,250 nTPM

Expression across tissuesHPA

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about MPO.

Disease | AllUniProt

Conditions MPO is implicated in, by any mechanism.

• Myeloperoxidase deficiency (MPOD) MIM:254600

Disease | GeneticClinVar

16 pathogenic / likely-pathogenic of 159 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

• Myeloperoxidase deficiency
• MPO-related disorder
• Alzheimer disease type 1
• Acute myeloid leukemia

Disease | ImmuneIEDB

Conditions an epitope on MPO was assayed in.

• rheumatoid arthritis B and T cell
• systemic scleroderma B cell
• autoimmune vasculitis B and T cell
• osteoarthritis B cell
• acute myeloid leukemia T cell

Disease | AutoantibodyPubMed

Conditions in which antibodies against MPO are reported. Each links to that disease's full target list.

• Vasculitis 167
• Glomerulonephritis 158
• Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis 106
• Granulomatosis with Polyangiitis 74
• Lupus Erythematosus, Systemic 33
• Scleroderma, Systemic 24
• Kidney Diseases 21
• Glomerulonephritis, IGA 17
• Arthritis, Rheumatoid 14
• Anti-Glomerular Basement Membrane Disease 13
• Acute Kidney Injury 11
• Lung Diseases, Interstitial 11
• Graves Disease 10
• Colitis, Ulcerative 9
• Renal Insufficiency 9
• Arthritis 8
• Lupus Nephritis 7
• Glomerulonephritis, Membranous 6
• Kidney Failure, Chronic 6
• Nephritis 6

Showing 20 of 49 — disease pages carrying at least 10 antigens.

ReferencesPubMed · IEDB

Publications for MPO from three distinct lines of evidence, kept separate because they answer different questions: whether antibodies are directed at the protein, whether a B-cell epitope has been mapped on it, and whether a T-cell epitope has. Each is labelled with its source.

Sources: PubMed — antigen-level antibody evidence from a custom retrieval. Records matching a controlled set of autoantibody terms (the MeSH descriptors Autoantibodies and Autoantigens, with title and abstract term variants) were obtained through NCBI E-utilities, and their titles and abstracts parsed for constructions that direct an antibody at a named protein rather than for co-occurrence. Captured names were resolved against UniProt nomenclature and each antigen adjudicated individually against the source text. IEDB — curated epitope assays from the Immune Epitope Database (Vita et al., Nucleic Acids Research 2019). Bibliographic records from PubMed and MeSH, U.S. National Library of Medicine; citation metrics from NIH iCite (Hutchins et al., PLoS Biology 2016). Titles link to PubMed; abstracts are not reproduced here. The NLM does not endorse this analysis.

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)

1.15

gnomAD pLI

0

gnomAD missense Z

0.32

DepMap mean gene effect

-0.13

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

• defense response
• defense response to bacterium
• defense response to fungus
• hydrogen peroxide catabolic process
• low-density lipoprotein particle remodeling
• negative regulation of apoptotic process
• removal of superoxide radicals
• respiratory burst involved in defense response
• response to food
• response to gold nanoparticle
• response to lipopolysaccharide
• response to mechanical stimulus
• response to oxidative stress
• response to yeast
• hypochlorous acid biosynthetic process

Molecular functions

• chromatin binding
• heme binding
• heparin binding
• metal ion binding
• peroxidase activity

Cellular components

• azurophil granule
• azurophil granule lumen
• extracellular exosome
• extracellular region
• extracellular space
• lysosome
• nucleoplasm
• nucleus
• phagocytic vesicle lumen
• secretory granule

Protein domainsUniProt · Pfam · InterPro

• Haem peroxidase superfamily
• Haem peroxidase, animal-type
• Haem peroxidase domain superfamily, animal type
• Animal haem peroxidase

KeywordsUniProt

• Calcium
• Disulfide bond
• Glycoprotein
• Heme
• Hydrogen peroxide
• Iron
• Lysosome
• Metal-binding
• Oxidation
• Oxidoreductase
• Peroxidase
• Signal

InteractionsUniProt · HPA

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

• CP