POT1

Protection of telomeres protein 1 is a protein that in humans is encoded by the POT1 gene.^[5][6][7]

POT1
Available structures PDB Ortholog search: PDBe RCSB List of PDB id codes 1XJV, 3KJO, 3KJP
Identifiers
Aliases	POT1, CMM10, HGLM9, protection of telomeres 1
External IDs	OMIM: 606478; MGI: 2141503; HomoloGene: 32263; GeneCards: POT1; OMA:POT1 - orthologs
Gene location (Human) Chr. Chromosome 7 (human)[1] Band 7q31.33 Start 124,822,386 bp[1] End 124,929,983 bp[1]
Gene location (Mouse) Chr. Chromosome 6 (mouse)[2] Band 6|6 A3.1 Start 25,743,736 bp[2] End 25,809,245 bp[2]
RNA expression pattern Bgee Human Mouse (ortholog) Top expressed in secondary oocyte germinal epithelium Achilles tendon sperm Epithelium of choroid plexus gastric mucosa gonad tibia ventricular zone retinal pigment epithelium Top expressed in genital tubercle tail of embryo zygote cumulus cell Gonadal ridge renal corpuscle ventricular zone primitive streak epiblast thymus More reference expression data BioGPS More reference expression data
Gene ontology Molecular function DNA binding telomeric DNA binding single-stranded telomeric DNA binding DEAD/H-box RNA helicase binding protein binding G-rich strand telomeric DNA binding telomerase inhibitor activity G-rich single-stranded DNA binding telomeric D-loop binding telomeric G-quadruplex DNA binding 8-hydroxy-2'-deoxyguanosine DNA binding Cellular component nuclear telomere cap complex nucleoplasm chromosome telomere nucleus shelterin complex Biological process negative regulation of telomerase activity DNA duplex unwinding positive regulation of helicase activity positive regulation of telomerase activity establishment of protein localization to telomere telomere assembly positive regulation of DNA strand elongation telomere maintenance telomere capping regulation of DNA helicase activity positive regulation of DNA helicase activity telomeric D-loop disassembly telomere maintenance via telomerase regulation of telomere maintenance via telomerase negative regulation of telomere maintenance via telomerase positive regulation of telomere maintenance via telomerase Sources:Amigo / QuickGO
Orthologs Species Human Mouse Entrez 25913 101185 Ensembl ENSG00000128513 ENSMUSG00000029676 UniProt Q9NUX5 Q91WC1 RefSeq (mRNA) NM_001042594 NM_015450 NM_133931 RefSeq (protein) NP_001036059 NP_056265 NP_001036059.1 NP_598692 Location (UCSC) Chr 7: 124.82 – 124.93 Mb Chr 6: 25.74 – 25.81 Mb PubMed search [3] [4]
Wikidata
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Function

This gene is a member of the telombin family and encodes a nuclear protein involved in telomere maintenance. Specifically, this protein functions as a member of a multi-protein complex known as shelterin, that binds to the TTAGGG repeats of telomeres, regulating telomere length and protecting chromosome ends from illegitimate recombination, catastrophic chromosome instability, and abnormal chromosome segregation. Alternatively spliced transcript variants have been described.^[7]

The absence of POT1 in mouse embryonic fibroblasts and chicken cells leads to a detrimental DNA damage response on telomeres resulting in telomere dysfunction-induced foci (TIFs). POT1 is required for telomere protection because it allows for telomere inhibition of DNA damage response factors. The protein also serves a role in the regulation of telomerase activity on telomeres. In vitro experiments utilizing human POT1 have shown that reduction in POT1 levels result in the elongation of telomeres.^[8]

Interactions

POT1 has been shown to interact with ACD^[9][10][11] and TINF2.^[10][11][12]

Pathology

• Increased transcriptional expression of this gene is associated with stomach carcinogenesis and its progression.
• Mutations in this gene have also been associated to the acquisition of the malignant features of chronic lymphocytic leukemia.^[13]
• POT1 loss-of-function variants predispose to familial melanoma^[14] and glioma.^[15]