ApoE/LDLR双基因突变小鼠肝脏差异表达蛋白组研究

Differential proteomic analysis of liver in apoE/LDLR double-gene mutant mice

目的:分析脂代谢相关双基因突变(apoE-/-/LDLR-/-)小鼠肝脏蛋白质表达特点,研究差异表达蛋白与基因突变小鼠血脂代谢紊乱和动脉粥样硬化的关系。方法:应用双向电泳及质谱技术对5周龄双基因突变和野生型小鼠肝组织差异蛋白进行比较研究。结果:双基因突变和野生型小鼠肝脏中分别检测到(928±15)和(1 017±50)个蛋白点(n=3),两者之间的平均匹配率分别为78.7%和83.2%。双基因突变小鼠有108个蛋白点未能与野生型小鼠匹配,相差5倍以上的上调点和下调点分别为10个和45个,取其中6个点做质谱分析,鉴定为endoplasmin precursor,acidic leucin-rich nuclear phosphoprotein 32 family member A,serotransferrin precursor,stress-70 protein precursor,fibronectin precursor,complement C3 precursor,fibrinogen gamma polypeptide 7种蛋白质。结论:双基因突变小鼠与野生型小鼠的肝脏蛋白表达谱有明显差异,推测这些蛋白在脂代谢相关双基因突变引发的小鼠血脂代谢紊乱在动脉粥样硬化的发生发展中可能发挥重要作用。

AIM： To comparatively study the differential expression of protein profiles of liver between double lipid metabolism genes mutant （apoE ^-/-/LDLR^ -/- ） and wild type（WT） mice. The key proteins related to atherosclerosis and dysfunction of lipid metabolism were also characterized. METHODS ： Two - dimensional gel electrophoresis and mass spectrometry were used to analyze the differential displayed proteomics of 5 - week - old double - gene mutants and wild type mice fed a regular chow for 2 weeks. RESULTS： Approximately （928 ± 15） spots and （ 1 017 ±50） spots were detected in apoE-/-/LDLR-/- mice （n = 3） and WT mice livers （n = 3）, respectively. The average matched ratio was 78. 7% and 83.2%. The differential expression analysis showed that the matched spots between apoE -/-/LDLR -/- mice and WT mice existed. Compared with the wild type, 108 spots were not matched in apoE^ -/-/LDLR^-/- mice. 10 over expression spots （ 〉5 fold） and 45 lower expression spots （ 〉5 fold） were noted. Six significant differential proteins in gel were identified by LTQ - ESI, e.g. endoplasmin precursor, acidic leucin - rich nuclear phosphoprotein 32 family member A, serotransferrin precursor, stress- 70 protein precursor, fibronectin precursor, complement C3 precursor, fibrinogen gamma polypeptide. CONCLUSION： The protein profile of apoE ^-/-/LDLR ^-/- mouse liver exhibits significant difference compared to that of WT mice. The results imply that lipid metabolism relative polygenetic mutation contributes to the alteration of mouse liver protein expression profile, especially that lipid metabolism related perhaps participates in dysfunction in lipid metabolism during atherogenesis.