Siebens-Drake Research Institute, 1400 Western Road, London, Ontario N6G 2 V4, Canada.
Cell Commun Signal. 2014 Jan 11;12:5. doi: 10.1186/1478-811X-12-5.
Dual oxidase maturation factor 1 (DUOXA1) has been associated with the maturation of the reactive oxygen species (ROS) producing enzyme, dual oxidase 1 (DUOX1) in the adult thyroid. However, ROS have also been implicated in the development of several tissues. We found that activated muscle satellite cells and primary myoblasts isolated from mice express robust levels of DUOXA1 and that its levels are altered as cells differentiate.
To determine whether DUOXA1 levels affect muscle differentiation, we used an adenoviral construct (pCMV5-DUOXA1-GFP) to drive constitutive overexpression of this protein in primary myoblasts. High levels of DUOXA1 throughout myogenesis resulted in enhanced H2O2 production, fusion defects, reduced expression of early (myogenin) and late (myosin heavy chain) markers of differentiation, and elevated levels of apoptosis compared to control cells infected with an empty adenoviral vector (pCMV5-GFP). DUOXA1 knockdown (using a DUOXA1 shRNA construct) resulted in enhanced differentiation compared to cells subjected to a control shRNA, and subjecting DUOXA1 overexpressing cells to siRNAs targeting DUOX1 or apoptosis signal-regulating kinase 1 (ASK1) rescued the phenotype.
This study represents the first to demonstrate the importance of DUOXA1 in skeletal muscle myoblasts and that DUOXA1 overexpression in muscle stem cells induces apoptosis and inhibits differentiation through DUOX1 and ASK1.
双氧化酶成熟因子 1(DUOXA1)与活性氧(ROS)产生酶——双氧化酶 1(DUOX1)在成人甲状腺中的成熟有关。然而,ROS 也与几种组织的发育有关。我们发现,激活的肌肉卫星细胞和从小鼠分离的原代成肌细胞表达高水平的 DUOXA1,并且随着细胞分化,其水平发生改变。
为了确定 DUOXA1 水平是否影响肌肉分化,我们使用腺病毒构建体(pCMV5-DUOXA1-GFP)在原代成肌细胞中驱动该蛋白的组成型过表达。在整个成肌过程中 DUOXA1 的高水平导致 H2O2 产生增加、融合缺陷、早期(肌生成素)和晚期(肌球蛋白重链)分化标志物的表达减少以及凋亡水平升高,与感染空腺病毒载体(pCMV5-GFP)的对照细胞相比。与接受对照 shRNA 的细胞相比,DUOXA1 敲低(使用 DUOXA1 shRNA 构建体)导致分化增强,并且用靶向 DUOX1 或凋亡信号调节激酶 1(ASK1)的 siRNAs 处理过表达 DUOXA1 的细胞挽救了表型。
这项研究首次证明了 DUOXA1 在骨骼肌成肌细胞中的重要性,并且在肌肉干细胞中过表达 DUOXA1 通过 DUOX1 和 ASK1 诱导凋亡并抑制分化。