Craniosynostosis-associated gene nell-1 is regulated by runx2.

摘要: We studied the transcriptional regulation of NELL-1, a craniosynostosis-related gene. identitifed three OSE2 elements in NELL-1 promoter that are directly bound and transactivated by Runx2. Forced expression Runx2 induces rat calvarial cells. Introduction: previously reported upregulation human craniosynostosis overexpression Nell-1 transgenic animals induced premature suture closure associated with increased osteoblast differentiation. To study we analyzed 5′ flanking region identified specific binding 2 (OSE2) sites (A, B, C) within 2.2 kb upstream transcription start site further functionality these sites. Materials Methods: An area truncated 325 bp, which lacked OSE sites, were cloned into luciferase reporter gene, co-transfected plasmid. The individually mutated plasmid Saos2 cells. Gel shifts supershifts antibodies used to determine sites. CHIP assays vivo promoter. was transfected wildtype Runx2−/− Nell-1, osteocalcin, levels measured using RT-PCR. Results: Addition dose-dependently activity promoter-luciferase p2213. p325 construct showed significantly lower basal level activity. Nuclear extract from cells formed complexes A, C probes supershifted antibody. Mutation decreased Furthermore, mutation B had blunted response Runx2, whereas A lesser effect. vivo. Transfection osteoblasts upregulated Ocn expression, null cells, both rescued. Conclusions: binds transactivates These results suggest is likely downstream target findings may also extend our understanding molecular mechanisms governing pathogenesis craniosynostosis.