目的 观察槲皮素-7,4′-二硫酸酯二钠(SQDS)对重组人肌醇磷脂3-激酶(PI3-K)p110β催化亚基的直接作用。方法 通过基因工程技术的方法获得PI3-Kp110β催化亚基,用PtdIns(4,5)P2和[γ-32P]ATP与重组PI3-Kp110β催化亚基一起保温的方法测定PI3-K的活性;32P标记的磷脂用氯仿和甲醇抽提,加闪烁液于液闪计数仪计数。结果 SQDS对重组人PI3-Kp110β催化亚基有抑制作用,IC50为14.88μmol/L。结论 SQDS是PI3-K的抑制剂。重组人PI3-Kp110β催化亚基可作为一种较为简便地筛选和开发有效的PI3-K抑制剂的分子靶点。

Objective To study the effect of disodium quercetin-7,4′-disulfate (SQDS) on activity ofrecombinant human phosphoinositide 3-kinase (PI3-K) p110βcatalytic subunit. Methods Recombinanthuman PI3-K p110βcatalytic subunit was expressed by gene engineering. PI3-K activity was assayed byincubating recombinant PI3-K p110βwith phosphatidylinositol-4,5-bisphosphate and [γ-32P] ATP;the32P-radiolabeled lipids were extracted with chloroform and methanol,then assessed by scintillation counter.Results SQDS showed inhibition on the recombinant p110βcatalytic subunit with IC5014.88μmol/L.Conclusion SQDS is an inhibitor of PI3-K. The recombinant PI3-K p110βcatalytic subunit might be usedas a molecular target for simpler screening and development of more effective inhibitors of PI3-K.

广东省重点学科基金资助项目(9306);广东医学院青年基金资助项目(XQ9901)