Abstract: By incubation of virion with 〔α- 32P〕GTP, 〔α- 32P〕ATP, 〔α- 32P〕CTP and 〔α- 32P〕UTP and Northwestern blotting, the function of structural proteins from rice gall dwarf virus (RGDV) was determined. In the structural proteins, the P1 was the putative RNA-dependent RNA polymerase, which might play an important role in the synthesis of RGDV genomic dsRNAs;The P5 bound with GTP and UTP was a NTP binding protein with RNA guanylyltransferase activity that synthesized a cap structure (mGpppAmpGp) for mRNA of RGDV; The P6 was RNA binding protein and might play an important role in RGDV particle package, as a “key protein” for the assembly of genomic RGDV dsRNAs into the viral particle. The structural protein with the strongest binding ability to nucleic acid was the nucleic acid binding protein of the protein P7 in rice dwarf virus (RDV) which has the similar biological function with the structural protein of the protein P6 in RGDV; the second one was RNA-dependent RNA polymerase; and the lowest one was RNA guanylyltransferase. It indicated that the biological function of the three structural proteins of RDV or RGDV could be judged auxiliary by their binding ability to the nucleic acid.

Key words: rice gall dwarf virus, rice dwarf virus, RNA-dependent RNA polymerase, RNA guanyltransferase, RNA binding protein

摘要： 采用α-32P标记的三磷酸核苷酸与病毒粒子共浴的方法及Northwestern分子杂交方法，研究证明了RGDV结构蛋白中，P1蛋白可能是依赖于RNA的RNA聚合酶， P5蛋白可能具有RNA鸟苷酰转移酶功能,P6蛋白可能是核酸结合蛋白，是RGDV复制包装中的关键蛋白。与RGDV结构蛋白具有相同生物功能的RDV的核酸结合蛋白与核酸的结合能力最强，依赖于RNA的RNA聚合酶与核酸的结合能力次之，RNA鸟苷酰转移酶与核酸的结合能力最弱。结果暗示了可以根据与核酸的结合能力，辅助判断RDV或RGDV这3个结构蛋白的生物功能。

关键词: 水稻瘤矮病病毒, 水稻矮缩病病毒, 依赖于RNA的RNA聚合酶, RNA鸟苷酰转移酶, 核酸结合蛋白