Department of Periodontology, Nihon University School of Dentistry at Matsudo, Chiba, 271-8587, Japan.
Gene. 2011 May 1;476(1-2):46-55. doi: 10.1016/j.gene.2011.01.016. Epub 2011 Jan 26.
Interleukin-11 (IL-11) is a stromal cell-derived cytokine that belongs to the interleukin-6 family of cytokines. IL-11 has many biological activities and has roles in hematopoiesis, immune responses, the nervous system and bone metabolism. Bone sialoprotein (BSP) is a mineralized tissue-specific protein expressed in differentiated osteoblasts that appears to function in the initial mineralization of bone. IL-11 (20 ng/ml) increased BSP mRNA and protein levels at 12h in osteoblast-like ROS 17/2.8 cells. In a transient transfection assay, IL-11 (20 ng/ml) increased luciferase activity of the construct (-116 to +60) in ROS 17/2.8 cells and rat bone marrow stromal cells. Introduction of 2 bp mutations to the luciferase constructs showed that the effects of IL-11 were mediated by a cAMP response element (CRE), a fibroblast growth factor 2 response element (FRE) and a homeodomain protein-binding site (HOX). Luciferase activities induced by IL-11 were blocked by protein kinase A inhibitor, tyrosine kinase inhibitor and ERK1/2 inhibitor. Gel shift analyses showed that IL-11 (20 ng/ml) increased nuclear protein binding to CRE, FRE and HOX. CREB1, phospho-CREB1, c-Fos, c-Jun, JunD and Fra2 antibodies disrupted the formation of CRE-protein complexes. Dlx5, Msx2, Runx2 and Smad1 antibodies disrupted FRE- and HOX-protein complex formations. These studies demonstrate that IL-11 stimulates BSP transcription by targeting CRE, FRE and HOX sites in the proximal promoter of the rat BSP gene. Moreover, phospho-CREB1, c-Fos, c-Jun, JunD, Fra2, Dlx5, Msx2, Runx2 and Smadl transcription factors appear to be key regulators of IL-11 effects on BSP transcription.
白细胞介素-11（IL-11）是一种基质细胞衍生的细胞因子，属于白细胞介素-6 细胞因子家族。IL-11 具有多种生物学活性，在造血、免疫反应、神经系统和骨代谢中发挥作用。骨涎蛋白（BSP）是一种矿化组织特异性蛋白，在分化的成骨细胞中表达，似乎在骨的初始矿化中发挥作用。在成骨样 ROS 17/2.8 细胞中，IL-11（20ng/ml）在 12 小时增加 BSP mRNA 和蛋白水平。在瞬时转染测定中，IL-11（20ng/ml）增加了 ROS 17/2.8 细胞和大鼠骨髓基质细胞中构建体（-116 至+60）的荧光素酶活性。荧光素酶构建体中的 2bp 突变引入表明，IL-11 的作用是通过 cAMP 反应元件（CRE）、成纤维细胞生长因子 2 反应元件（FRE）和同源盒蛋白结合位点（HOX）介导的。蛋白激酶 A 抑制剂、酪氨酸激酶抑制剂和 ERK1/2 抑制剂阻断了由 IL-11 诱导的荧光素酶活性。凝胶移位分析表明，IL-11（20ng/ml）增加了核蛋白与 CRE、FRE 和 HOX 的结合。CREB1、磷酸化 CREB1、c-Fos、c-Jun、JunD 和 Fra2 抗体破坏了 CRE-蛋白复合物的形成。Dlx5、Msx2、Runx2 和 Smad1 抗体破坏了 FRE 和 HOX-蛋白复合物的形成。这些研究表明，IL-11 通过靶向大鼠 BSP 基因近端启动子中的 CRE、FRE 和 HOX 位点刺激 BSP 转录。此外，磷酸化 CREB1、c-Fos、c-Jun、JunD、Fra2、Dlx5、Msx2、Runx2 和 Smad1 转录因子似乎是 IL-11 对 BSP 转录影响的关键调节剂。
