LGI1

Leucine-rich, glioma inactivated 1, also known as LGI1, is a protein which in humans is encoded by the LGI1 gene.^[5] It may be a metastasis suppressor.

LGI1
Identifiers
Aliases	LGI1, ADLTE, ADPAEF, ADPEAF, EPITEMPIN, EPT, ETL1, IB1099, leucine-rich, glioma inactivated 1, leucine rich glioma inactivated 1
External IDs	OMIM: 604619; MGI: 1861691; HomoloGene: 3737; GeneCards: LGI1; OMA:LGI1 - orthologs
Gene location (Human) Chr. Chromosome 10 (human)[1] Band 10q23.33 Start 93,757,840 bp[1] End 93,806,272 bp[1]
Gene location (Mouse) Chr. Chromosome 19 (mouse)[2] Band 19|19 C3 Start 38,252,984 bp[2] End 38,300,662 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in pons Brodmann area 23 endothelial cell caudate nucleus putamen middle temporal gyrus Epithelium of choroid plexus nucleus accumbens lateral nuclear group of thalamus superior frontal gyrus Top expressed in dentate gyrus dentate gyrus of hippocampal formation granule cell hippocampus proper primary visual cortex temporal lobe amygdala superior frontal gyrus subdivision of hippocampus subiculum Region I of hippocampus proper More reference expression data BioGPS More reference expression data
Gene ontology Molecular function signaling receptor binding protein binding Cellular component extracellular region cell junction synapse extracellular space membrane synaptic cleft glutamatergic synapse Biological process positive regulation of cell growth cell population proliferation neuron projection development positive regulation of synaptic transmission protein homooligomerization nervous system development axon guidance neurotransmitter receptor localization to postsynaptic specialization membrane Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 9211 56839 Ensembl ENSG00000108231 ENSMUSG00000067242 UniProt O95970 Q9JIA1 RefSeq (mRNA) NM_001308275 NM_001308276 NM_005097 NM_020278 RefSeq (protein) NP_001295204 NP_001295205 NP_005088 NP_064674 Location (UCSC) Chr 10: 93.76 – 93.81 Mb Chr 19: 38.25 – 38.3 Mb PubMed search [3] [4]
Wikidata
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Function

The leucine-rich glioma inactivated -1 gene is rearranged as a result of translocations in glioblastoma cell lines. The protein contains a hydrophobic segment representing a putative transmembrane domain with the amino terminus located outside the cell. It also contains leucine-rich repeats with conserved cysteine-rich flanking sequences. This gene is predominantly expressed in neural tissues and its expression is reduced in low grade brain tumors and significantly reduced or absent in malignant gliomas.^[5]

Clinical significance

Since its earliest discovery, the LGI1 gene has been implicated in the control of cancer metastasis and in a predisposition to epilepsy. Following genetic linkage studies placing the hereditary form of autosomal dominant partial epilepsy with auditory features (ADPEAF) on chromosome region 10q24^[6][7] mutation analysis of affected members in these families^[8][9][10] demonstrated LGI1 was a major cause of the disease.

More recently, LGI1 has been shown to be the major target of human autoantibodies^[11][12][13] which immunoprecipitate voltage-gated potassium channel complexes from mammalian brain tissue. LGI1 antibodies are found in patients with limbic encephalitis and in patients with faciobrachial dystonic seizures (FBDS). FBDS are a recently described form of epilepsy which is characterized by frequent, brief seizures which affect the arm and face. They appear to be preferentially responsive to immunotherapy over anti-epileptic drugs.

Interactions

LGI1 has been shown to interact with ADAM22,^[14] and DLG4.^[14]