人牙本质磷蛋白功能片段的原核表达

Prokaryotic Expression of human dentin phosphoprotein domain

目的本研究旨在利用分子生物学技术原核表达包含功能区的人DPP片段。方法首先构建带有人DPP基因5′端序列的GST融合蛋白表达质粒。经IPTG诱导表达,SDS-PAGE电泳。结果人牙本质磷蛋白基因5′端序列可在原核表达系统中进行不溶性表达,表达的融合蛋白分子量约为43KDa,进行初步纯化后,经SDS-PAGE证实,在预期位置出现了纯化蛋白条带。结论利用GST融合蛋白表达系统表达了人DPP功能片段。为进一步通过对人DPP功能片段的研究揭示DPP在牙齿发育和牙髓修复中的作用及其机制奠定基础。

Objective To clone and express the human DPP domain containing DSS was cloned and expressed using genetic engineering in prokaryotic expression system. Methods The 50d-bp long fragment of human DPP gene was isolated from plasmid pT-DPP-N and subcloned into a GST （fusion protein） expression vector pGEX-5X-1. Results SDS-PAGE assays yielded a roughly 43000 Da expressed protein at the expected mobility position, which presented in inclusion body. After lysed with urea solution, the expressed proteins were separated from bacteria lysates with a commercially supplied chromatography sepharose 4B. Conclusion Human DPP domain is cloned and expressed using GST （ fusion protein） expression system, which will lay a foundation for further study on the role of DPP in tooth development and pulp restoration.