| First Author | Kikuchi T | Year | 2003 |
| Journal | J Dent Res | Volume | 82 |
| Issue | 7 | Pages | 546-50 |
| PubMed ID | 12821717 | Mgi Jnum | J:187216 |
| Mgi Id | MGI:5435880 | Doi | 10.1177/154405910308200712 |
| Citation | Kikuchi T, et al. (2003) Cot/Tpl2 is essential for RANKL induction by lipid A in osteoblasts. J Dent Res 82(7):546-50 |
| abstractText | Lipopolysaccharide (LPS) is a pathogenic factor that increases bone resorption in periodontal diseases. LPS treatment of osteoblasts was shown to induce the receptor activator of NF-kappa B ligand (RANKL), an essential secretory or membrane-bound factor for osteoclast function, in a manner dependent on extracellular signal-regulated kinase (ERK) activation. However, the mechanisms regulating this process remained unknown. Here, we show that RANKL mRNA induction and ERK activation, when treated with synthetic lipid A (an active center of LPS), were markedly reduced in mouse osteoblasts lacking Cot/Tpl2, which was recently recognized as an essential kinase for the induction of TNF-alpha by LPS in macrophages. In contrast, c-Jun N-terminal kinase (JNK), p38 kinase, Raf-1, and NF-kappa B were normally activated in cot/tpl2-/- osteoblasts. These findings indicate that Cot/Tpl2 is essential for LPS-induced ERK activation and RANKL induction in osteoblasts. |
