MIR875: MIR875 is a microRNA that is transcribed from a tooth-specific transcription start site (TSS) in the chromosome 15qD1 region [PMC7080778]. The TSS of MIR875 can be accurately predicted using CAGE analysis [PMC7080778]. The promoter region of MIR875 can be bound by the transcription co-activator PRRX1/2, which induces the expression of MIR875 [PMC7080778]. The function of PRRX1/2 in the MIR875 promoter was confirmed using luciferase reporter vectors [PMC7080778]. Additionally, PRRX1 and PRRX2 were found to bind to the promoter region of MIR875 and induce its expression [PMC7080778]. The JASPAR database was used to identify potential transcription factors that can bind to the promoter region of MIR875 [PMC7080778]. Mutant reporter plasmids were constructed to study the function of specific sequences in the MIR875 promoter [PMC7080778]. qRT-PCR and RNA-sequence analysis confirmed the expression of MIR875 in tooth samples [PMC7080778]. The findings suggest that PRRXs regulate MIR875 expression and may play a role in dental mesenchymal cell differentiation during tooth development [PMC7080778]. Furthermore, it has been suggested that miRNAs, including MIR875, participate in different processes related to wood formation and tooth germ development [PMC9081728] [PMC8633455] . Overall, these findings indicate that MIR875 may be a critical regulator of dental mesenchymal migration and condensation during tooth morphogenesis, potentially through its interaction with PDGF signaling pathway via epithelial-mesenchymal interaction during tooth morphogenesis[ PMC9081728] . Additionally, PRRX1 has been implicated in tumor metastasis and can bind to the promoter region of MIR875 to stimulate the maturation of miR-875-5p and promote tumor cell migration [PMC8291965].