【摘要】 从猪血中分离得到血小板,经反复洗涤后用Triton X-100(1％)溶解血小板,以DEAE纤维素作离子交换层析,经梯度洗脱后,洗脱组分以Dot-blotting放射自显影法进行钙结合活性测定,收集钙结合活性最强的洗脱组分,再以羟基磷灰石作吸附层析,用磷酸缓冲液作梯度洗脱,分离纯化了一种具有较强钙结合活性的蛋白质。SDS-聚丙烯酰胺凝胶电泳(PAGE)测定其分子量为5.4×10~4。该蛋白质能够促进天然磷脂酰丝氨酸(PS)脂质体聚集,并且这种作用依赖钙离子的存在。提示该蛋白质可能属于一类新的钙结合蛋白——Annexins,其功能可能与钙调节的血小板分泌有关,或在血小板骨架成分与膜相互作用时起关键的桥梁作用。更多还原

【Abstract】 Porcine platelet was washed repeatedly with PWS B, then dissolved in Triton X-100. The platelet lysate was applied on DEAE ion-exchange column and eluated with linear gradient eluation. The calcium binding activity of the fraction was assayed by Dot-blotting autoradiography. The active fraction was purified further on hydroxy apatite column, eluated with linear gradient eluation of phosphate buffer. A calcium binding protein was found in this eluant. The molecular weight of this protein is MW 5.4×104 as determined by SDS-polyacrylamide gel electrophoresis (PAGE). This protein was shown to enhance Ca2+-induced aggregation of phosphatidylserine (PS) lipoSome. It indicates thatthis protein may be a member of a new class of calcium binding protein-----Anne-xin. Its function may be related to the calcium regulated platelet secretion, or to play an important role in the interaction between platelet cytoskeleton and membrane.更多还原