Platelet endothelial aggregation receptor-1 regulates bovine muscle satellite cell migration and differentiation via integrin beta-1 and focal adhesion kinase

PEAR1 is highly expressed at bovine MDSC differentiation. However, its biological function remains unclear. Western blotting results showed that PEAR1 increased between day 0 and day 2 of cell differentiation and decreased from day 3. Moreover, scratch test showed that wound healing rate increased after PEAR1 overexpression and decreased upon its suppression. Meanwhile, we found that, upon PEAR1 induction, both the expression of the focal adhesion-associated and MyoG, and the myotube fusion rate increased. However, when PEAR1 was suppressed, opposite results were obtained. Immunoprecipitation revealed an association between PEAR1 and ITGB1. Notably, inhibition of FAK and ITGB1 repressed cell differentiation. In conclusion, our study indicated that PEAR1 is involved in the regulation of bovine MDSC migration and differentiation.

血小板内皮聚集受体1（PEAR1）在牛髓系来源抑制细胞（myeloid-derived suppressor cells, MDSC）的分化过程中呈高表达，但其具体生物学功能仍未明确。蛋白质免疫印迹实验结果显示，PEAR1在细胞分化第0天至第2天期间表达量升高，自第3天起表达量下降。此外，划痕实验结果表明，过表达PEAR1可提升细胞创面愈合率，而抑制PEAR1的表达则会降低该愈合速率。同时，研究发现，诱导PEAR1表达后，黏着斑相关蛋白、肌细胞生成素（Myogenin, MyoG）的表达水平以及肌管融合率均有所提升；而当PEAR1的表达被抑制时，则会得到截然相反的实验结果。免疫共沉淀实验证实，PEAR1与整合素β1（Integrin β1, ITGB1）存在相互作用。值得注意的是，抑制黏着斑激酶（Focal Adhesion Kinase, FAK）与ITGB1的活性会阻碍细胞分化。综上，本研究表明PEAR1参与调控牛髓系来源抑制细胞的迁移与分化过程。