Inositol monophosphatase 1

IMPA1
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1AWB, 1IMA, 1IMB, 1IMC, 1IMD, 1IME, 1IMF, 2HHM, 4AS4
Identifiers
Aliases	IMPA1, IMP, IMPA, inositol monophosphatase 1, MRT59
External IDs	OMIM: 602064 MGI: 1933158 HomoloGene: 4043 GeneCards: IMPA1
EC number	3.1.3.94
Gene location (Human) Chr. Chromosome 8 (human)[1] Band 8q21.13 Start 81,656,914 bp[1] End 81,686,331 bp[1]
Gene location (Mouse) Chr. Chromosome 3 (mouse)[2] Band 3|3 A1 Start 10,377,016 bp[2] End 10,396,499 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in secondary oocyte jejunal mucosa endothelial cell tibia right ventricle Brodmann area 23 bronchial epithelial cell retinal pigment epithelium middle temporal gyrus rectum Top expressed in motor neuron ciliary body retinal pigment epithelium iris Paneth cell facial motor nucleus conjunctival fornix external carotid artery primitive streak epithelium of stomach More reference expression data BioGPS More reference expression data
Gene ontology Molecular function inositol monophosphate phosphatase activity manganese ion binding protein homodimerization activity metal ion binding lithium ion binding protein binding identical protein binding hydrolase activity magnesium ion binding inositol monophosphate 1-phosphatase activity inositol monophosphate 4-phosphatase activity inositol monophosphate 3-phosphatase activity Cellular component cytoplasm cytosol Biological process inositol metabolic process inositol biosynthetic process inositol phosphate metabolic process phosphatidylinositol phosphate biosynthetic process phosphate-containing compound metabolic process phosphatidylinositol biosynthetic process signal transduction inositol phosphate dephosphorylation Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 3612 55980 Ensembl ENSG00000133731 ENSMUSG00000027531 UniProt P29218 O55023 RefSeq (mRNA) NM_005536 NM_001144878 NM_001144879 NM_018864 NM_001310433 RefSeq (protein) NP_001138350 NP_001138351 NP_005527 n/a Location (UCSC) Chr 8: 81.66 – 81.69 Mb Chr 3: 10.38 – 10.4 Mb PubMed search [3] [4]
Wikidata
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Inositol monophosphatase 1 is an enzyme that in humans is encoded by the IMPA1 gene.^[5][6]

Interacting partners

IMPA1 has been shown to interact with Bergmann glial S100B^[7] and calbindin.^[8][9]

Chemical inhibitors

L-690,330 is a competitive inhibitor of IMPase activity with very good activity in vitro however with limited bioavailability in vivo.^[10] Due to its increased specificity compared to Lithium, L-690,330 has been used extensively in characterizing the results of IMPase inhibition in various cell culture models. L-690,488, a prodrug or L-690,330, has also been developed which has greater cell permeability. Treatment of cortical slices with L-690,488 resulted in accumulation of inositol demonstrating the activity of this inhibitor in tissue.^[11]

Inhibition of IMPA1 activity can have pleiotropic effects on cellular function, including altering phosphoinositide signalling,^[12] autophagy, apoptosis,^[13] and other effects.

Bipolar disorder

Initially it was noticed that several drugs useful in treatment of bipolar disorder such as lithium, carbamazepine and valproic acid had a common mechanism of action on enzymes in the phosphatidylinositol signalling pathway^[14] and the inositol depletion hypothesis for the pathophysiology of bipolar disorder was suggested. Intensive research has so far not confirmed this hypothesis, partly because lithium can also act on a number of other enzymes in this pathway, complicating results from in vitro studies.

References

Further reading

External links

• PDBe-KB provides an overview of all the structure information available in the PDB for Human Inositol monophosphatase 1