CUT - Tag detection results for H3K9la, H4K8la, and H4K16la in tenocyte

We found that lactate and lactylation were significantly elevated in rotator cuff tears, and lactylation primarily regulates histones in tenocytes. Therefore, we screened for histone lactylation and identified that H3K9, H4K8, and H4K16 had the most prominent increases. Subsequently, we conducted CUT - Tag assays on them. The results indicated that H3K9la was enriched at the promoters of ENO3 and COL1, while H4K16la was enriched at the promoter of TNMD, which induced the transcriptional expression of these genes. Moreover, as a glycolytic enzyme, ENO3 is further involved in the H3K9la–Eno3–lactate–H3K9la positive feedback loop to maintain a high lactate level. This feedback loop continuously drives the H3K9 - COL1 and H4K16 - TNMD regulatory axes, ultimately promoting the repair of rotator cuff tear injuries.我们发现，肩袖撕裂 (rotator cuff tears) 病变组织中乳酸 (lactate) 与乳酸化 (lactylation) 水平显著升高，且乳酸化主要调控肌腱细胞 (tenocytes) 内的组蛋白。因此，我们针对组蛋白乳酸化 (histone lactylation) 进行筛选，鉴定出H3K9、H4K8及H4K16的乳酸化修饰水平升高最为显著。随后，我们针对这三个位点开展了CUT-Tag实验。结果显示，H3K9乳酸化修饰 (H3K9la) 富集于ENO3与COL1的启动子区域，而H4K16乳酸化修饰 (H4K16la) 则富集于TNMD的启动子区域，进而诱导上述基因的转录表达。此外，作为糖酵解酶的ENO3还参与构建H3K9la-ENO3-乳酸-H3K9la正反馈环路，以维持高乳酸水平；该正反馈环路持续驱动H3K9-COL1与H4K16-TNMD调控轴发挥功能，最终促进肩袖撕裂损伤的修复。