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Characterization of PAXIP1 in alternative lengthening of telomeres

ABSTRACT: Telomere length maintenance is essential for cellular immortalization and tumorigenesis. About 10% − 15% of human cancers rely on the recombination-based alternative lengthening of telomeres (ALT) to sustain their replicative immortality, yet the underlying molecular mechanism remains incompletely understood. Here we found the chromatin binding protein PAXIP1 as a novel ALT regulator and identified PAGR1 as its main functional protein partner. Mechanistically, we show that PAXIP1/PAGR1 complex complements with the PML nuclear body scaffold protein to promote ALT-directed telomere maintenance, independently from its MLL3/MLL4 complex-associated transcriptional function. We propose PAXIP1/PAGR1 complex as a functional component of break-induced telomere repair.

ORGANISM(S): Homo sapiens

PROVIDER: GSE314012 | GEO | 2026/01/01

REPOSITORIES: GEO

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