| [ Summary ] |
AP-1 (activator protein-1) is a collection of stress-responsive dimeric transcription factors typically composed of Fos and Jun proteins. Deletion or overexpression of AP-1 family members in mice often dramatically affect osteoclastic or osteoblastic differentiation. Since AP-1 also regulates expression of a number of inflammatory cytokines, chemokines and other immune mediators, mice lacking or overexpressing an AP-1 gene frequently show impaired innate and acquired immune responses. Thus, AP-1 is a pivotal transcription factor functioning in both bone metabolism and immune defense. |