Increased Telomere Mobility in Progeria is Restored by Isoprenylcysteine Carboxyl Methyltransferase Inhibition.

Hutchinson-Gilford Progeria Syndrome (HGPS) is a genetic disease characterized by the accumulation of progerin, a mutant form of lamin A, at the nuclear envelope. Progerin disrupts the stability of the nuclear lamina, leading to genome instability and accelerated aging phenotypes. While structural nuclear defects are well-documented, the impact of progerin on real-time chromatin dynamics and the ability of current therapeutics to rescue these dynamics remains poorly understood. In this work, we employ single-particle tracking to quantify telomere dynamics in HGPS patient fibroblasts. We demonstrate that HGPS cells exhibit significantly increased telomere dynamics, characterized by expanded scan areas, increased diffusion coefficients, and larger jump distances compared to healthy controls. We further evaluated the efficacy of two clinically relevant treatments, the farnesyltransferase inhibitor Lonafarnib and the ICMT inhibitor C75, to determine if emerging treatments can restore chromatin dynamics compared to healthy controls. Our results reveal that Lonafarnib partially rescues telomere dynamics, shifting chromatin motion back towards healthy control levels, and that C75 provides a complete rescue of the dynamics for all parameters quantified. These findings provide a quantitative framework for understanding how nuclear lamina mutations induce aberrant genome dynamics and the efficacy of HGPS therapies on restoring those dynamics.