| First Author | Ludwik KA | Year | 2020 |
| Journal | Cell Rep | Volume | 32 |
| Issue | 3 | Pages | 107931 |
| PubMed ID | 32697984 | Mgi Jnum | J:300608 |
| Mgi Id | MGI:6488854 | Doi | 10.1016/j.celrep.2020.107931 |
| Citation | Ludwik KA, et al. (2020) RSK2 Maintains Adult Estrogen Homeostasis by Inhibiting ERK1/2-Mediated Degradation of Estrogen Receptor Alpha. Cell Rep 32(3):107931 |
| abstractText | In response to estrogens, estrogen receptor alpha (ERalpha), a critical regulator of homeostasis, is degraded through the 26S proteasome. However, despite the continued presence of estrogen before menopause, ERalpha protein levels are maintained. We discovered that ERK1/2-RSK2 activity oscillates during the estrous cycle. In response to high estrogen levels, ERK1/2 is activated and phosphorylates ERalpha to drive ERalpha degradation and estrogen-responsive gene expression. Reduction of estrogen levels results in ERK1/2 deactivation. RSK2 maintains redox homeostasis, which prevents sustained ERK1/2 activation. In juveniles, ERK1/2-RSK2 activity is not required. Mammary gland regeneration demonstrates that ERK1/2-RSK2 regulation of ERalpha is intrinsic to the epithelium. Reduced RSK2 and enrichment in an estrogen-regulated gene signature occur in individuals taking oral contraceptives. RSK2 loss enhances DNA damage, which may account for the elevated breast cancer risk with the use of exogenous estrogens. These findings implicate RSK2 as a critical component for the preservation of estrogen homeostasis. |
