In this installment of the Longevity & Aging Series, Dr. Julia Sidorova from the Department of Laboratory Medicine and Pathology at the University of Washington (Seattle, WA) joined host Dr. Evgeniy Galimov to discuss her co-authored research paper from Volume 16, Issue 20 of Aging (Aging-US), titled “Werner syndrome RECQ helicase participates in and directs maintenance of the protein complexes of constitutive heterochromatin in proliferating human cells.” DOI - https://doi.org/10.18632/aging.206132 Corresponding Author - Julia M. Sidorova - julias@uw.edu Video interview - https://www.youtube.com/watch?v=3yn8O-JA6GE Abstract Werner syndrome of premature aging is caused by mutations in the WRN RECQ helicase/exonuclease, which functions in DNA replication, repair, transcription, and telomere maintenance. How the loss of WRN accelerates aging is not understood in full. Here we show that WRN is necessary for optimal constitutive heterochromatin levels in proliferating human fibroblasts. Locally, WRN deficiency derepresses SATII pericentromeric satellite repeats but does not reduce replication fork progression on SATII repeats. Globally, WRN loss reduces a subset of protein-protein interactions responsible for the organization of constitutive heterochromatin in the nucleus, namely, the interactions involving Lamin B1 and Lamin B receptor, LBR. Both the mRNA level and subcellular distribution of LBR are affected by WRN deficiency, and unlike the former, the latter phenotype does not require WRN catalytic activities. The phenotypes of heterochromatin disruption seen in WRN-deficient proliferating fibroblasts are also observed in WRN-proficient fibroblasts undergoing replicative or oncogene-induced senescence. WRN interacts with histone deacetylase 2, HDAC2; WRN/HDAC2 association is mediated by heterochromatin protein alpha, HP1α, and WRN complexes with HP1α and HDAC2 are downregulated in senescing cells. The data suggest that the effect of WRN loss on heterochromatin is separable from senescence program, but mimics at least some of the heterochromatin changes associated with it. Sign up for free Altmetric alerts about this article - https://aging.altmetric.com/details/email_updates?id=10.18632%2Faging.206132 Subscribe for free publication alerts from Aging - https://www.aging-us.com/subscribe-to-toc-alerts Keywords - aging, Werner progeria, heterochromatin, senescence, nuclear lamina, satellite repeats About Aging-US The mission of the journal is to understand the mechanisms surrounding aging and age-related diseases, including cancer as the main cause of death in the modern aged population. The journal aims to promote 1) treatment of age-related diseases by slowing down aging, 2) validation of anti-aging drugs by treating age-related diseases, and 3) prevention of cancer by inhibiting aging. (Cancer and COVID-19 are age-related diseases.) Please visit our website at https://www.Aging-US.com​​ and connect with us: Facebook - https://www.facebook.com/AgingUS/ X - https://twitter.com/AgingJrnl Instagram - https://www.instagram.com/agingjrnl/ YouTube - https://www.youtube.com/@AgingJournal LinkedIn - https://www.linkedin.com/company/aging/ Pinterest - https://www.pinterest.com/AgingUS/ Spotify - https://open.spotify.com/show/1X4HQQgegjReaf6Mozn6Mc MEDIA@IMPACTJOURNALS.COM