Table 3.
CRISPR/Cas9 for bone repair.
| Target gene | Repair Mechanism | Research progress | Literature |
|---|---|---|---|
| ELMO1 | ELMO1 promotes enhanced osteoclast activity and increases bone resorption activity. Knock-out. | Deleted the ELMO1 gene in Hoxb8 macrophages (osteoclast precursor cells) via CRISPR/Cas9 and sgRNA. Then the transfected macrophages developed functional defects. | Arandjelovic et al., [86] 2021 |
| Noggin | High expression of BMP2 upregulates the expression of osteogenic genes and induces differentiation of stem cells into osteoblasts. Noggin can bind BMP2 and prevent its docking with stem cell surface receptors. Knock-down. | Gene editing mediated by a hybrid baculovirus system that prolongs BMP2 expression and reduces Noggin expression. | Hsu et al., [89] 2020 |
| BMP9 | BMP9 induces differentiation of stem cells to osteoblasts by activating Smad-dependent signaling pathways. Upregulation. | MSCs were genetically edited to overexpress BMP9 using the CRISPR/Cas9 system. | Freitas et al., [92] 2021 |
| Sox9 and PPAR-γ | Sox9 and PPAR-γ act as major transcription factors for cartilage and adipose formation respectively, and PPAR-γ inhibits the action of Sox9. Activation of Sox9 while inhibiting PPAR-γ promotes bone healing. Knock-down. | The CRISPRai system was constructed using the large capacity of the baculovirus vector. CRISPRai could be combined to stimulate tissue regeneration for bidirectional regulation. | Truong et al., [93] 2019 |
| USP11 | USP11 overexpression enhances the expression of osteogenic factors in BMSCs. MSX1 balances the level of protein degradation during normal osteogenesis. Upregulation. | Used the CRISPR/Cas9 system to screen for deubiquitinating enzymes (DUBs) that regulate MSX1 protein. | Kaushal et al., [95] 2022 |
| Wnt16 | The Wnt pathway plays an important role in the osteogenic differentiation of BMSCs. Wnt16 is a ligand that affects stem cell proliferation, differentiation and migration through the Wnt pathway. Knock-out. | Generated stable Wnt16 −/− mutant zebrafish lines using CRISPR/Cas9 technology to study their effects on bone tissue using tissue mineral density (TMD) as an observation. | McGowan et al., [98] 2021 |
| Satb2 | Deletion of Satb2 may result in incomplete expression of osteogenic genes or poor skeletal development. Mutation. | Used the CRISPR/Cas9 system to induce mutations in the Satb2 gene in MC3T3-E1 cells. When Satb2 expression is reduced, the growth rate of osteoblasts is slowed down. | Dowrey et al., [100] 2019 |