人工构建镉盐污染源,选用差速离心结合双向凝胶电泳(2D—PAGE)法,高效提取、分离和筛选牙鲆(Paralichthys olivaceus,PO)受镉盐胁迫后的肝脏全蛋白和差异蛋白质。实验结果表明:选用直接裂解法提取牙鲆肝(PO liver POL)全蛋白质且用2D—PAGE分离,可获得约800个蛋白斑点,其中镉盐诱导了11个差异蛋白斑点。以相对离心力为1000×g、12000×g和100000×g的差速离心法,分别制备了3种沉淀蛋白和1种胞浆蛋白,称为POL组分Ⅰ、POL组分Ⅱ、POL组分Ⅲ和POL组分Ⅳ(胞浆蛋白),蛋白斑点数目分别为380、550、500和850个,总计2280个,明显高于直接裂解法。比较分析法发现,差速离心结合2D—PAGE分离技术可获得牙鲆肝脏受镉盐胁迫后表达的54个差异蛋白质,并适合于用肽质量指纹(peptide mass fingerprint,PMF)图谱技术鉴定。本实验所建立的差速离心结合蛋白质组学技术可高效提取、分离和鉴定组织全蛋白或差异蛋白,并能有效地筛选出蛋白指示物。
Both total proteome and differential proteins were effectively extracted, separated and selected by a combined approach of both differential centrifugation and 2D-PAGE in liver of Paralichtys olivaceus (POL) under the stress of cadmium chloride as an artificial pollution source. Approximately 800 spots for extraction of whole protein separated with 2D-PAGE were obtained by direct lysis in the POL. In addition, approximately 11 differential proteins in POL were also obtained under the stress of cadmium chloride. The differential centrifugal were used to prepare three sedimentation and a plasmolysis proteins, called POL component Ⅰ, POL component Ⅱ, POL component Ⅲ, and POL component IV (plasmolysis protein), respectively. Total protein spots for each gel were calculated to have 380,550, 500, and 850, respectively, approximately 2280 spots in sum, while total spots are much higher than those by direct lysis approach. Using the comparison method, approximately 54 differential proteins in POL were obtained by a combined technology of both differential and two dimensional polyacylaminde gel electrophoresis(2D-PAGE) methods under the stress of cadmium chloride. In addition, these differential proteins can be further identified by peptide mass fingerprint (PMF). Here, these combined techniques can be effectively used to extract, separate and identify the whole proteins and the differential proteins including protein markers in the biological tissue.