用二维电泳和质谱技术筛选4.5 Gy照射比格犬差异表达蛋白质的初步研究

Initial research of screening for the differentially expressed proteins in beagles irradiated with 4.5 Gy^60 CO γ-rays by two-dimensional gel electrophoresis and mass spectrometry

目的 从分子水平探索细胞因子治疗急性放射病的作用机制.方法 4.5 Gy γ射线照射后收集不同时间点细胞因子治疗组比格犬血清,应用二维电泳分离血清中差异表达的蛋白质,找出其中差异显著的蛋白质点进行质谱分析,并确定蛋白质的氨基酸序列.结果 获得了分辨率较高的凝胶蛋白图谱.共筛选出6个差异表达蛋白质点,成功鉴定出其中的4个蛋白质点.经氨基酸序列分析发现其中一个较有意义的蛋白质是相对分子质量为13 077、等电点为6.26的血清淀粉样蛋白A（SAA）.该蛋白在照射前及照后36 d均无表达,照射后1 d略有增强（吸光度为0.2166）,14 d显著增强（吸光度为0.4577）.结论 SAA的表达变化与病程进展相一致,可能对病情的转归有重要的提示意义.

Objective To explore the mechanisms of cytokines on acute radiation disease in irradiated beagles.Methods The sera of beagles irradiated with 4.5 Gy γ-rays with cytokines treatment was collected at different time points post irradiation.The two-dimensional gel electrophoresis（2-DE）was used to isolate and compare the differentially expressed proteins in sera.HD-MS was used to analyze the differentially expressed proteins with significance,and the amino acid sequences should be determined. Results High resolution 2-DE gel map was obtained.There were six differentially expressed proteins in sera of irradiated beagles at different time points.Four protein spots were successfully identified by MS.A significant spot was identified as serum amyloid A（SAA）by HD-MS,with relative molecular mass of 13 077 and isoelectfie point of 6.26.Expression of SAA was not found 1 d pre-irradiation and 36 d postirradiation,but increased slightly 1 d（0.2166）and significantly 14 d post-irradiation（0.4577）. Conclusions The expression of serum amyloid A was consistent with the process of acute radiation injury,which might indicate the turnover of the disease.