SIRT1 suppresses LINE-1 retrotransposon activity by stabilizing heterochromatin-modifying complexes at the L1 promoter region. SIRT1 deficiency permits L1 transcription, which activates inflammatory pathways and accelerates cellular senescence—a hallmark of aging and age-related disease.
Key Points
- SIRT1 recruits Lamin B1 and KAP1 to silence L1 retrotransposons.
- L1 activation without SIRT1 triggers cGAS-STING pathway and senescence.
- L1 suppression delays senescence and genomic instability.
Longevity Analysis
This research identifies a direct molecular link between SIRT1 activity and genomic stability through the suppression of endogenous retrotransposons. When SIRT1 function declines—as occurs with age—L1 elements become transcriptionally active, triggering innate immune signaling that drives cells into permanent senescence. Because senescent cells accumulate with age and secrete pro-inflammatory factors, controlling L1 activity emerges as a mechanism by which SIRT1 extends healthy lifespan. The pathway suggests that interventions preserving SIRT1 function or directly suppressing L1 retrotransposition may slow the transition from genomic quiescence to the inflammatory state characteristic of aging.
Original published by Wiley Aging Cell, by Xiaona Wang, Tianbo Li, Huanyin Tang, Meng Xiao Liu, Qinghua Peng, Xiao Huang, Zhiyong Mao, Ying Jiang, Anke Geng .