Senescence-induced Spatio-temporal Re-organization of the Nuclear Lamina Dynamic Landscape at Single-molecule Level in Live Human RPE Cells
Year: 2026
Type: preprint
Abstract: ABSTRACT A defining hallmark of cellular senescence is the extensive remodeling of the nuclear lamina (NL) in both structure, composition, and its interactions with lamina-associated genomic domains. However, how such senescence-induced changes could quantitatively impact the spatio-temporal dynamics of NL interactions at the single-molecule level remain poorly understood. Herein, using human retinal pigment epithelium (RPE) cells as model system, we establish a robust, chemically inducible cellular senescence model capable of recapitulating key signatures of the senescence-associated phenotype. Senescent RPE cells exhibit distinct alteration patterns in the expression of various NL components, including lamin B receptor (LBR) and emerin, two key mediators of NL– chromatin interactions. Importantly, live-cell diffusion measurements via imaging FCS reveal globally enhanced mobility for both LBR and emerin, indicative of weakened NL anchoring in senescent cells. Single-molecule tracking and super-resolved STAR mapping further unveil distinct, multi-modal re-organization of their NL-binding dynamics in both space and time (especially in the form of LBR binding “hotspots” where multiple stable binding events cluster to effect more extended and prolonged interaction), in line with their respective expression-level alterations and differential lamin interactions. Moreover, correlative mapping uncovers a strong spatial coupling between reduced LBR mobility and highly condensed constitutive heterochromatin domains at the NL, which become dispersed during senescence. Collectively, these findings demonstrate the re-organization of NL dynamic landscape at single-molecule level as a critical and previously under-explored facet of senescence-induced NL remodeling, and point to a synergistic interplay between physical de-anchoring, dynamic attenuation of stable NL-binding and spatial restructuring of chromatin architecture in modulating NL–heterochromatin contacts to potentially effect global changes in senescence-associated gene expression. STATEMENT OF SIGNIFICANCE In this study, we combine a suite of quantitative imaging and transcriptomic profiling approaches with complementary capabilities and perform, to our knowledge, the first rigorous characterization of the impact of cellular senescence on the spatio-temporal dynamics of NL interactions at the single-molecule level in live human cells. Our findings not only reveal a key and previously overlooked dimension of NL remodeling during cellular senescence, but also shed first-of-its-kind quantitative insights into a mechanism by which the multi-modal binding landscape at the NL work in concert with higher-order chromatin architecture and NL–chromatin anchoring to modulate the contacts between NL and heterochromatin, which can in turn alter the global gene expression program to drive senescence.
Institutions: National University of Singapore, Mechanobiology Institute
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: green
Award: G1213292995
OpenAlex ID: W7221128986