Abstract

Objective We aimed to explore the role of Heterogeneous Nuclear Ribonucleoprotein L(hnRNP L ) in enamel organ development through hnRNP L conditional knockout mice and knockdown of hnRNP L expression in mouse ameloblast-lineage cells (mALCs) Methods We created K14cre-mediated hnRNP L conditional knockout mice ( hnRNP L K14/fl ) and silenced the expression of hnRNP L in mALCs to investigate the role of hnRNP L in enamel organ development. Results We found that hnRNP L K14/fl mice presented enamel organ development defects with reduced number of inner enamel epithelium (IEE) cells. The proliferation and differentiation of the IEE cells/ameloblasts were suppressed. The cell proliferation and mineralization ability were also decreased after hnRNP L knockdown. Further studies showed that Bone Morphogenetic Protein (BMP) signaling pathway was attenuated after the knockdown of hnRNP L expression both in vivo and in vitro. Conclusions These findings suggest that hnRNP L plays a critical role in enamel organ development by promoting the IEE cell/ameloblast proliferation and differentiation. BMP signaling pathway may be involved in the process.