干细胞与材料之间的相互作用对细胞分化和组织再生的影响是当前再生医学研究中的热点，细胞骨架是细胞与材料之间相互作用的主要因素，然而基于生物材料的生物牙根再生分子机制尚不清楚。申请人前期研究发现（Exp Cell Res. 2016），细胞骨架结合蛋白l-CaD等可能是牙源性干细胞分化及牙根再生的重要调控分子。处理牙本质基质（TDM）是一种具有成牙本质诱导功能的天然细胞外基质（ECM）类材料，然而l-CaD在TDM与牙源性干细胞之间的相互作用中的功能和调控机制尚不清楚。本研究拟通过TDM与牙周膜细胞共培养体系，研究l-CaD在TDM诱导牙周膜细胞成牙本质分化中的作用，以肌动蛋白细胞骨架的动态变化为切入点，阐明l-CaD在牙周膜细胞成牙本质分化过程中的机制，并分析l-CaD在牙胚发育中的作用。本研究将为牙源性干细胞分化提供新的分子机制，并为TDM诱导细胞成牙本质分化和组织再生提供理论依据。

The interaction between stem cells and materials on cell differentiation and tissue regeneration is one of the hot topic in regenerative medicine. The cytoskeleton is the major factor in cell-material interaction. However, the mechanism of the biomaterials based bio-root regeneration is still unclear. Our previous study (Exp Cell Res. 2016) found that the cytoskeleton binding proteins such as low molecular weight caldesmon (l-CaD) may be the key regulator in dental derived stem cell differentiation and tooth root regeneration. Treated dentin matrix (TDM) is a natural extracellular matrix (ECM) material with odontogenic differentiation ability. However, the function and molecular mechanism of l-CaD in the interaction between TDM and dental derived stem cells are still unclear. In this study, the role of l-CaD in TDM-induced periodontal ligament cells differentiation will be investigated through TDM and periodontal ligament cell co-culture system. The dynamic changes of actin cytoskeleton will be used as the starting point to elucidate the mechanism of l-CaD in the process of odontogenic differentiation of periodontal ligament cells. In addition, the role of l-CaD in tooth development will be discussed. This study will provide new molecular mechanism for the differentiation of dental derived stem cells and further provide theoretical basis for TDM-induced odontogenic differentiation and tissue regeneration.