PML2‐mediated thread‐like nuclear bodies mark late senescence in Hutchinson–Gilford progeria syndrome [RNA-seq]

Regular nuclear structure is critical for genome maintenance and proper gene expression, disorder of which has a causal role in aging. Accumulation of Progerin in Hutchinson-Gilford progeria syndrome (HGPS) disrupts the integrity of nuclear lamina and causes nuclear structure abnormalities, leading to premature aging. However, the nuclear structure/function relationships in HGPS cells have not been well addressed, and roles of nuclear sub-compartments for HGPS pathogenesis are rarely reported. Here, evidence reveals that classical dot-like PML nuclear bodies (PML NBs) are reorganized into thread-like morphology in HGPS cells, and these irregular NBs are strongly associated with cell senescence. We demonstrate that farnesylated Progerin interacts with PML isoform 2 specifically, which accounts for the formation of thread-like PML NBs. Moreover, our findings uncover that irregular PML NBs perturb NBs-associated DNA repair and gene transcription, thereby promoting HGPS cell senescence. Thus, our work helps to clarify the roles of nuclear structure and sub-compartments such as PML NBs in cell aging, and evidence presented in this study strongly support that thread-like PML NBs could be a novel biomarker of human cell senescence.