Senescence-associated heterochromatic foci-related proteins (SAHF-related proteins)

Senescence-associated heterochromatic foci (SAHF) are specialized domains of facultative heterochromatin that form in the nuclei of senescent cells to silence proliferation-promoting genes, such as E2F targets. The formation of SAHF is a multi-step process involving the HIRA/ASF1A histone chaperone complex, which deposits histone variants like macroH2A and facilitates the recruitment of heterochromatin protein 1 (HP1) and high mobility group A (HMGA) proteins. These proteins are considered therapeutic targets in the context of pro-senescence therapy for cancer or senolytic therapy to eliminate senescent cells that contribute to chronic inflammation. Drugs like histone deacetylase inhibitors (HDACis) can perturb SAHF structure, leading to the reactivation of DNA damage responses and subsequent apoptosis in senescent cells. Understanding the downstream expression patterns associated with SAHF is crucial for identifying biomarkers of cellular aging and developing targeted interventions for age-related pathologies. While SAHF formation is primarily a tumor-suppressive mechanism, the persistence of senescent cells can lead to tissue dysfunction, making the modulation of these chromatin structures a key area of research in longevity and oncology.

Other names

SAHF proteinsSenescence-associated heterochromatin proteinsHIRA-ASF1A complexHMGA proteinsHP1 proteins

Histone deacetylase inhibition and chromatin relaxation to induce apoptosis in senescent cells (senolysis).