Histamine H 4 receptor
| Histamine H 4 receptor | ||
|---|---|---|
| Properties of human protein | ||
| Mass / length primary structure | 390 AS ; 44.5 kDa | |
| Secondary to quaternary structure | 7TM | |
| Identifier | ||
| Gene name | HRH4 | |
| External IDs | ||
| Occurrence | ||
| Parent taxon | Vertebrates | |
The histamine H 4 receptor (abbreviated H 4 receptor ) is a protein from the family of histamine receptors that by the body's tissue hormone histamine can be activated. In the human body, the H 4 receptor is found in particular on cells of the blood-forming system and the immune system . The receptor is involved in allergic reactions .
biochemistry
genetics
The human H 4 receptor was first cloned in 2000 by various research groups as a homologue of the histamine H 3 receptor . It is encoded by a gene on chromosome 18 on the gene locus 18q11.2. The coding DNA sequence contains three exons and two introns and shows the highest homology to the histamine H 3 receptor.
Protein structure
The human H 4 receptor protein consists of 390 amino acids . Other variants of the H 4 receptor that arise from alternative splice variants are functionally inactive. As for many other receptors from the family of G protein-coupled receptors , a structure with seven helical transmembrane domains is assumed for the H 4 receptor ( heptahelical receptor ).
Signal transduction
At the molecular level, stimulation of H 4 receptors leads to activation of G i / o proteins , inhibition of adenylyl cyclase and opening of calcium channels .
function
H 4 receptors are involved in the targeted migration of immune cells such as eosinophil granulocytes , T lymphocytes and monocytes to sources of histamine. Therefore, it is believed that this receptor plays an important role in the recruitment of leukocytes during an immune response, particularly allergic reactions.
pharmacology
Histamine antagonists at the H 4 receptor, such as JNJ 7777120, are currently being investigated for their therapeutic potential in the treatment of allergic diseases. 4-methylhistamine and VUF-8430 could be identified as selective agonists .
Individual evidence
- ^ Van Rijn RM, van Marle A, Chazot PL, Langemeijer E, Qin Y, Shenton FC, Lim HD, Zuiderveld OP, Sansuk K, Dy M, Smit MJ, Tensen CP, Bakker RA, Leurs R: Cloning and characterization of dominant negative splice variants of the human histamine H4 receptor . In: Biochem J . 414, No. 1, 2008, pp. 121-131. PMID 18452403 .