China Agricultural University, Beijing, Peoples Republic of China.
Cell Biol Int. 2010 Nov;34(11):1119-27. doi: 10.1042/CBI20090351.
Fusion of monomyoblasts to form multinucleated myotubes is a prerequisite for skeletal myogenesis, and muscle fibroblast-myoblast interaction plays an important role in the process; however, relative studies are limited. In the current study, SLD (sex-linked dwarf) chicken, a myogenic deficient model caused by GH (growth hormone)-IGF-I axis deficiency due to dw gene mutation, was introduced to study effects of fibroblasts on myodifferentiation. Using a membrane insert co-culture system, we identified that, compared with SLD fibroblasts, normal fibroblasts promoted myogenesis of primary SLD myoblasts by improving their differentiation potential in a paracrine fashion, and this effect was involved in both primary and secondary fusions. This process was also coupled with up-regulation of β1 integrin, and reduced myogenesis, resulting from siRNA interference demonstrated that β1 integrin was required for the response. Further, in terms of genetic discrepancy between normal and SLD fibroblasts, GH-IGF-I signalling might play a role in this paracrine control.
成肌细胞融合形成多核肌管是骨骼肌发生的前提条件，而肌肉成纤维细胞-成肌细胞的相互作用在该过程中起着重要作用；然而，相关研究有限。在本研究中，引入了性连锁矮小（SLD）鸡，这是一种由于 dw 基因突变导致 GH（生长激素）-IGF-I 轴缺陷引起的肌生成缺陷模型，用于研究成纤维细胞对成肌分化的影响。使用膜插入共培养系统，我们确定与 SLD 成纤维细胞相比，正常成纤维细胞通过旁分泌方式改善其分化潜能来促进原代 SLD 成肌细胞的成肌分化，这种作用涉及到原代和次代融合。这一过程还伴随着 β1 整合素的上调，而 siRNA 干扰导致的成肌减少表明，β1 整合素是这种反应所必需的。此外，就正常和成纤维细胞之间的遗传差异而言，GH-IGF-I 信号可能在这种旁分泌控制中发挥作用。
