Histamine N-methyltransferase

Histamine N-methyltransferase
Crystallographic structure of human histamine N-methyltransferase.[1]
Available structures PDB Ortholog search: PDBe, RCSB List of PDB id codes 1ICZ​, 1JQD​, 1JQE​, 2AOT​, 2AOU​, 2AOV​, 2AOW​, 2AOX​
Identifiers
Symbols	HNMT ; HMT; HNMT-S1; HNMT-S2
External IDs	OMIM: 605238 HomoloGene: 5032 GeneCards: HNMT Gene
EC number	2.1.1.8
Gene ontology Molecular function • histamine N-methyltransferase activity Cellular component • nucleoplasm • cytoplasm • neuron projection • extracellular exosome Biological process • response to tumor cell • hyperosmotic response • brain development • respiratory gaseous exchange • response to amine • methylation • response to immobilization stress • response to cocaine • response to glucocorticoid • response to interleukin-1 • positive regulation of protein targeting to mitochondrion Sources: Amigo / QuickGO
Orthologs
Species	Human	Mouse
Entrez	3176	140483
Ensembl	ENSG00000150540	ENSMUSG00000026986
UniProt	P50135	Q91VF2
RefSeq (mRNA)	NM_001024074	NM_080462
RefSeq (protein)	NP_001019245	NP_536710
Location (UCSC)	Chr 2: 137.96 – 138.02 Mb	Chr 2: 24 – 24.05 Mb
PubMed search

histamine N-methyltransferase
Identifiers
EC number	2.1.1.8
CAS number	9029-80-5
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / EGO
Search PMC articles PubMed articles NCBI proteins

Histamine N-methyltransferase (HMT, HNMT) is an enzyme that in humans is encoded by the HNMT gene.^[2]

Histamine N-methyltransferase is one of two enzymes involved in the metabolism of histamine, the other being diamine oxidase. Histamine N-methyltransferase catalyzes the methylation of histamine in the presence of S-adenosylmethionine (SAM) forming N-methylhistamine. HMT is present in most body tissues but is not present in serum.^[3] Histamine N-methyltransferase is encoded by a single gene which has been mapped to chromosome 2.

Function

In mammals, histamine is metabolized by two major pathways: N(tau)-methylation via histamine N-methyltransferase and oxidative deamination via diamine oxidase. This gene encodes the first enzyme which is found in the cytosol and uses S-adenosyl-L-methionine as the methyl donor. In the mammalian brain, the neurotransmitter activity of histamine is controlled by N(tau)-methylation as diamine oxidase is not found in the central nervous system. A common genetic polymorphism affects the activity levels of this gene product in red blood cells.^[2]

References

1. PDB: 1JQD​; Horton JR, Sawada K, Nishibori M, Zhang X, Cheng X (September 2001). "Two polymorphic forms of human histamine methyltransferase: structural, thermal, and kinetic comparisons". Structure 9 (9): 837–49. doi:10.1016/S0969-2126(01)00643-8. PMID 11566133.
2. "Entrez Gene: Histamine N-methyltransferase".
3. Brown DD, Tomchick R, Axelrod J (November 1959). "The distribution and properties of a histamine-methylating enzyme" (pdf). J. Biol. Chem. 234 (11): 2948–50. PMID 13804910.

Further reading

• Wang L, Thomae B, Eckloff B, Wieben E, Weinshilboum R (August 2002). "Human histamine N-methyltransferase pharmacogenetics: gene resequencing, promoter characterization, and functional studies of a common 5'-flanking region single nucleotide polymorphism (SNP)". Biochem. Pharmacol. 64 (4): 699–710. doi:10.1016/s0006-2952(02)01223-6. PMID 12167489.
• García-Martín E, Martínez C, Benito-León J, Calleja P, Díaz-Sánchez M, Pisa D, Alonso-Navarro H, Ayuso-Peralta L, Torrecilla D, Agúndez JA, Jiménez-Jiménez FJ (February 2010). "Histamine-N-methyl transferase polymorphism and risk for multiple sclerosis". Eur. J. Neurol. 17 (2): 335–8. doi:10.1111/j.1468-1331.2009.02720.x. PMID 19538200.
• Ross CJ, Katzov-Eckert H, Dubé MP, Brooks B, Rassekh SR, Barhdadi A, Feroz-Zada Y, Visscher H, Brown AM, Rieder MJ, Rogers PC, Phillips MS, Carleton BC, Hayden MR (December 2009). "Genetic variants in TPMT and COMT are associated with hearing loss in children receiving cisplatin chemotherapy". Nat. Genet. 41 (12): 1345–9. doi:10.1038/ng.478. PMID 19898482.
• Seip RL, Volek JS, Windemuth A, Kocherla M, Fernandez ML, Kraemer WJ, Ruaño G (2008). "Physiogenomic comparison of human fat loss in response to diets restrictive of carbohydrate or fat". Nutr Metab (Lond) 5: 4. doi:10.1186/1743-7075-5-4. PMC 2270845. PMID 18254975.
• Chen GL, Zhu B, Nie WP, Xu ZH, Tan ZR, Zhou G, Liu J, Wang W, Zhou HH (September 2004). "Single nucleotide polymorphisms and haplotypes of histamine N-methyltransferase in patients with gastric ulcer". Inflamm. Res. 53 (9): 484–8. doi:10.1007/s00011-004-1290-0. PMID 15551002.
• Szczepankiewicz A, Bręborowicz A, Sobkowiak P, Popiel A (2010). "Polymorphisms of two histamine-metabolizing enzymes genes and childhood allergic asthma: a case control study". Clin Mol Allergy 8: 14. doi:10.1186/1476-7961-8-14. PMC 2990726. PMID 21040557.
• Stevenson J, Sonuga-Barke E, McCann D, Grimshaw K, Parker KM, Rose-Zerilli MJ, Holloway JW, Warner JO (September 2010). "The role of histamine degradation gene polymorphisms in moderating the effects of food additives on children's ADHD symptoms". Am J Psychiatry 167 (9): 1108–15. doi:10.1176/appi.ajp.2010.09101529. PMID 20551163.
• Aksoy S, Raftogianis R, Weinshilboum R (February 1996). "Human histamine N-methyltransferase gene: structural characterization and chromosomal location". Biochem. Biophys. Res. Commun. 219 (2): 548–54. doi:10.1006/bbrc.1996.0271. PMID 8605025.
• Horton JR, Sawada K, Nishibori M, Zhang X, Cheng X (September 2001). "Two polymorphic forms of human histamine methyltransferase: structural, thermal, and kinetic comparisons". Structure 9 (9): 837–49. doi:10.1016/S0969-2126(01)00643-8. PMID 11566133.

External links

• Histamine N-Methyltransferase at the US National Library of Medicine Medical Subject Headings (MeSH)

This article incorporates text from the United States National Library of Medicine, which is in the public domain.