As an extracellular matrix protein, secreted protein acidic and rich in cysteine (SPARC)-like 1 (SPARCL1) is involved in various cell functions. It was previously implicated in bovine skeletal muscle-derived satellite cell (MDSC) differentiation; however, the underlying mechanism remains unknown. In this study, immunoprecipitation and mass spectrometry revealed that integrin β1 (ITGB1) combines with SPARCL1. Further, co-immunoprecipitation demonstrated that SPARCL1 interacts with ITGB1. Cell scratch assays explored the influence of SPARCL1 on MDSC migration through ITGB1. In addition, desmin staining for myotube fusion rate and MyoD protein expression results showed that SPARCL1 promotes MDSC early differentiation through ITGB1. Furthermore, Western blotting results demonstrated that SPARCL1 regulates the expression of p-FAK, p-paxillin, vinculin, Cdc42, and Arp2/3 through ITGB1. These findings indicate that SPARCL1 may influence bovine MDSC migration and differentiation through an ITGB1-mediated cell signaling pathway. Herein, we elucidated the mechanism through which SPARCL1 affects MDSC differentiation. Our results provide insight into the molecular mechanism of muscle development and may in the future facilitate skeletal muscle regeneration and treatment.

中文翻译：

---

SPARCL1通过ITGB1介导的信号通路影响牛骨骼肌衍生的卫星细胞迁移和分化。

作为一种细胞外基质蛋白，酸性且富含半胱氨酸（SPARC）样1（SPARCL1）的分泌蛋白参与各种细胞功能。它先前与牛骨骼肌衍生卫星细胞（MDSC）的分化有关。但是，其潜在机制仍然未知。在这项研究中，免疫沉淀和质谱分析表明整合素β1（ITGB1）与SPARCL1结合。此外，免疫共沉淀证明SPARCL1与ITGB1相互作用。细胞刮擦试验探索了SPARCL1对MDSC通过ITGB1迁移的影响。此外，结蛋白染色的肌管融合率和MyoD蛋白表达结果表明SPARCL1通过ITGB1促进MDSC早期分化。此外，蛋白质印迹结果表明SPARCL1调节p-FAK，p-paxillin，纽扣蛋白，Cdc42和Arp2 / 3（通过ITGB1）。这些发现表明SPARCL1可能通过ITGB1介导的细胞信号传导途径影响牛MDSC迁移和分化。在本文中，我们阐明了SPARCL1影响MDSC分化的机制。我们的结果提供了对肌肉发育的分子机制的了解，并可能在将来促进骨骼肌的再生和治疗。