粉纹夜蛾核型多角体病毒诱导的胸苷激酶特性研究

Characterization of Thymidine Kinase Activity Associated with the Replication of Trichoplusia ni Nuclear Polyhedrosis Virus

粉纹夜蛾(Trichoplusia ni)核型多角体病毒(TnNPV)感染草地贪夜蛾(Spodop-tera frugiperda)细胞后能诱导提高胸苷激酶的活性。不论是正常或感染细胞中的胸苷激酶都可将脱氧胞苷磷酸化,酶活最适pH及Mg^(++)离子浓度值基本相同,DEAE-纤维素和Cibacron blue-sepharose柱层析所得酶活性图谱亦相似。TnNPV在胸苷激酶缺陷型的草地贪夜蛾细胞中能正常复制,但被感染细胞不具有胸苷激酶活性。由此可以确定,经TnNPV感染诱导后,活性有所提高的胸苷激酶不是病毒基因编码的。

Trichoplusia ni nuclear polyhedrosis virus(TnNPV) stimulated thymidine kinase(TK) activities in infected Spodoptera frugiperda cells. TK activities both in infected and uninfected cells are similar in their pH, Mg^(++) optima for assays and elution patterns on DEAE-cellulose and Cibacron-blue sepharose chromatography. The facts that TnNPV could replicate in TK^- S. frugiperda cells but no TK activity was detected in the infected cells implies that the virus-stimulated activity was not contributed by the virus-coded enzyme.