Article ; Online: Genomic instability caused by Arp2/3 complex inactivation results in micronucleus biogenesis and cellular senescence.
2023 Volume 19, Issue 1, Page(s) e1010045
Abstract: The Arp2/3 complex is an actin nucleator with well-characterized activities in cell morphogenesis and movement, but its roles in nuclear processes are relatively understudied. We investigated how the Arp2/3 complex affects genomic integrity and cell ... ...
| Abstract | The Arp2/3 complex is an actin nucleator with well-characterized activities in cell morphogenesis and movement, but its roles in nuclear processes are relatively understudied. We investigated how the Arp2/3 complex affects genomic integrity and cell cycle progression using mouse fibroblasts containing an inducible knockout (iKO) of the ArpC2 subunit. We show that permanent Arp2/3 complex ablation results in DNA damage, the formation of cytosolic micronuclei, and cellular senescence. Micronuclei arise in ArpC2 iKO cells due to chromatin segregation defects during mitosis and premature mitotic exits. Such phenotypes are explained by the presence of damaged DNA fragments that fail to attach to the mitotic spindle, abnormalities in actin assembly during metaphase, and asymmetric microtubule architecture during anaphase. In the nuclei of Arp2/3-depleted cells, the tumor suppressor p53 is activated and the cell cycle inhibitor Cdkn1a/p21 mediates a G1 arrest. In the cytosol, micronuclei are recognized by the DNA sensor cGAS, which is important for stimulating a STING- and IRF3-associated interferon response. These studies establish functional requirements for the mammalian Arp2/3 complex in mitotic spindle organization and genome stability. They also expand our understanding of the mechanisms leading to senescence and suggest that cytoskeletal dysfunction is an underlying factor in biological aging. |
|---|---|
| MeSH term(s) | Animals ; Mice ; Actin-Related Protein 2-3 Complex/genetics ; Actin-Related Protein 2-3 Complex/metabolism ; Actins/metabolism ; Cellular Senescence/genetics ; DNA/metabolism ; Genomic Instability/genetics ; Mitosis/genetics |
| Chemical Substances | Actin-Related Protein 2-3 Complex ; Actins ; DNA (9007-49-2) |
| Language | English |
| Publishing date | 2023-01-27 |
| Publishing country | United States |
| Document type | Journal Article ; Research Support, N.I.H., Extramural |
| ZDB-ID | 2186725-2 |
| ISSN | 1553-7404 ; 1553-7390 |
| ISSN (online) | 1553-7404 |
| ISSN | 1553-7390 |
| DOI | 10.1371/journal.pgen.1010045 |
| Database | MEDical Literature Analysis and Retrieval System OnLINE |
More links
Kategorien
Order via subito
This service is chargeable due to the Delivery terms set by subito. Orders including an article and supplementary material will be classified as separate orders. In these cases, fees will be demanded for each order.