POT1

POT1 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 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. Increased transcriptional expression of this gene is associated with stomach carcinogenesis and its progression.

Full Name

Protection of Telomeres 1

Function

Component of the telomerase ribonucleoprotein (RNP) complex that is essential for the replication of chromosome termini. Is a component of the double-stranded telomeric DNA-binding TRF1 complex which is involved in the regulation of telomere length by cis-inhibition of telomerase. Also acts as a single-stranded telomeric DNA-binding protein and thus may act as a downstream effector of the TRF1 complex and may transduce information about telomere maintenance and/or length to the telomere terminus. Component of the shelterin complex (telosome) that is involved in the regulation of telomere length and protection. Shelterin associates with arrays of double-stranded TTAGGG repeats added by telomerase and protects chromosome ends; without its protective activity, telomeres are no longer hidden from the DNA damage surveillance and chromosome ends are inappropriately processed by DNA repair pathways. Binds to two or more telomeric single-stranded 5'-TTAGGG-3' repeats (G-strand) and with high specificity to a minimal telomeric single-stranded 5'-TAGGGTTAG-3' sequence. Binds telomeric single-stranded sequences internally or at proximity of a 3'-end. Its activity is TERT dependent but it does not increase TERT activity by itself. In contrast, the ACD-POT1 heterodimer enhances telomere elongation by increasing telomerase processivity.

Biological Process

DNA duplex unwindingManual Assertion Based On ExperimentIDA:BHF-UCL
Establishment of protein localization to telomereManual Assertion Based On ExperimentIMP:BHF-UCL
Negative regulation of telomerase activityManual Assertion Based On ExperimentIDA:BHF-UCL
Negative regulation of telomere maintenance via telomeraseManual Assertion Based On ExperimentIGI:BHF-UCL
Positive regulation of DNA helicase activityManual Assertion Based On ExperimentIDA:BHF-UCL
Positive regulation of DNA strand elongationManual Assertion Based On ExperimentIDA:BHF-UCL
Positive regulation of helicase activityManual Assertion Based On ExperimentIDA:BHF-UCL
Positive regulation of telomerase activityManual Assertion Based On ExperimentIDA:BHF-UCL
Positive regulation of telomere maintenance1 PublicationIC:ComplexPortal
Positive regulation of telomere maintenance via telomeraseManual Assertion Based On ExperimentIDA:BHF-UCL
Regulation of DNA helicase activityManual Assertion Based On ExperimentIDA:BHF-UCL
Regulation of double-strand break repair via nonhomologous end joiningManual Assertion Based On ExperimentIDA:CACAO
Regulation of telomere maintenance via telomeraseManual Assertion Based On ExperimentIGI:BHF-UCL
Telomere assemblyManual Assertion Based On ExperimentIDA:BHF-UCL
Telomere cappingManual Assertion Based On ExperimentIDA:ComplexPortal
Telomere maintenance via telomeraseManual Assertion Based On ExperimentIDA:UniProtKB
Telomeric D-loop disassemblyManual Assertion Based On ExperimentIGI:BHF-UCL

Cellular Location

Nucleus
Chromosome, telomere
Colocalizes with telomeric DNA.

Involvement in disease

Melanoma, cutaneous malignant 10 (CMM10):
A malignant neoplasm of melanocytes, arising de novo or from a pre-existing benign nevus, which occurs most often in the skin but also may involve other sites.
Glioma 9 (GLM9):
Gliomas are benign or malignant central nervous system neoplasms derived from glial cells. They comprise astrocytomas and glioblastoma multiforme that are derived from astrocytes, oligodendrogliomas derived from oligodendrocytes and ependymomas derived from ependymocytes.