Fukushima Taku, Hasegawa Yuka, Kuse Sachi, Fujioka Taiju, Nikawa Takeshi, Masubuchi Satoru, Sakakibara Iori
Department of Physiology, School of Medicine, Aichi Medical University, Nagakute, Aichi, Japan.
Department of Nutritional Physiology, Institute of Medical Nutrition, Tokushima University Graduate School, Tokushima, Japan.
PLoS One. 2024 May 3;19(5):e0301690. doi: 10.1371/journal.pone.0301690. eCollection 2024.
Myogenesis is regulated mainly by transcription factors known as Myogenic Regulatory Factors (MRFs), and the transcription is affected by epigenetic modifications. However, the epigenetic regulation of myogenesis is poorly understood. Here, we focused on the epigenomic modification enzyme, PHF2, which demethylates histone 3 lysine 9 dimethyl (H3K9me2) during myogenesis. Phf2 mRNA was expressed during myogenesis, and PHF2 was localized in the nuclei of myoblasts and myotubes. We generated Phf2 knockout C2C12 myoblasts using the CRISPR/Cas9 system and analyzed global transcriptional changes via RNA-sequencing. Phf2 knockout (KO) cells 2 d post differentiation were subjected to RNA sequencing. Gene ontology (GO) analysis revealed that Phf2 KO impaired the expression of the genes related to skeletal muscle fiber formation and muscle cell development. The expression levels of sarcomeric genes such as Myhs and Mybpc2 were severely reduced in Phf2 KO cells at 7 d post differentiation, and H3K9me2 modification of Mybpc2, Mef2c and Myh7 was increased in Phf2 KO cells at 4 d post differentiation. These findings suggest that PHF2 regulates sarcomeric gene expression via epigenetic modification.
肌生成主要由称为肌源性调节因子（MRFs）的转录因子调控，且转录受表观遗传修饰影响。然而，肌生成的表观遗传调控仍知之甚少。在此，我们聚焦于表观基因组修饰酶PHF2，其在肌生成过程中使组蛋白3赖氨酸9二甲基化（H3K9me2）去甲基化。Phf2 mRNA在肌生成过程中表达，且PHF2定位于成肌细胞和肌管的细胞核中。我们使用CRISPR/Cas9系统构建了Phf2基因敲除的C2C12成肌细胞，并通过RNA测序分析全局转录变化。对分化后2天的Phf2基因敲除（KO）细胞进行RNA测序。基因本体（GO）分析显示，Phf2基因敲除损害了与骨骼肌纤维形成和肌肉细胞发育相关基因的表达。在分化后7天，Phf2基因敲除细胞中肌节基因如Myhs和Mybpc2的表达水平严重降低，且在分化后4天，Phf2基因敲除细胞中Mybpc2、Mef2c和Myh7的H3K9me2修饰增加。这些发现表明，PHF2通过表观遗传修饰调节肌节基因表达。
