Ziros Panos G, Basdra Efthimia K, Papavassiliou Athanasios G
Department of Biological Chemistry, Medical School, University of Athens, Athens 11527, Greece.
Int J Biochem Cell Biol. 2008;40(9):1659-63. doi: 10.1016/j.biocel.2007.05.024. Epub 2007 Jun 26.
Runx2 is a key transcriptional modulator of osteoblast differentiation that plays a fundamental role in osteoblast maturation and homeostasis. Runx2-null mice despite normal skeletal patterning have no osteoblasts and consequently bone tissue. Mutations of the runx2 gene in humans cause cleidocranial dysplasia. As a member of the Runx family of transcription factors, Runx2 operates by binding to the osteoblast-specific cis-acting element 2 (OSE2), which is found in the regulatory region of all main osteoblast-related genes controlling their expression. Its expression and/or activity are dictated by a number of different external cues while multiple signalling pathways that affect osteoblast function merge to and are integrated by Runx2. Among the various stimuli that modulate Runx2 activity, mechanical loading (strain/stretching) has been revealed to be one of the most critical signals that connect Runx2 with osteoblast function and bone remodelling through mechanotransduction.
Runx2是成骨细胞分化的关键转录调节因子，在成骨细胞成熟和体内平衡中起重要作用。Runx2基因敲除小鼠尽管骨骼模式正常，但没有成骨细胞，因此也没有骨组织。人类runx2基因的突变会导致锁骨颅骨发育不全。作为Runx转录因子家族的成员，Runx2通过与成骨细胞特异性顺式作用元件2（OSE2）结合发挥作用，OSE2存在于所有主要成骨细胞相关基因的调控区域，控制其表达。它的表达和/或活性由许多不同的外部信号决定，而影响成骨细胞功能的多个信号通路汇聚并由Runx2整合。在调节Runx2活性的各种刺激中，机械负荷（应变/拉伸）已被证明是通过机械转导将Runx2与成骨细胞功能和骨重塑联系起来的最关键信号之一。
