DNA and RNA polymerase activities of nuclei and hypotonic extracts of nuclei isolated from tomato golden mosaic virus infected tobacco leaves
Author
Coutts, Robert H.A.
Buck, K.W.
Attention
2299/11116
Abstract
Nuclei and hypotonically leached extracts of nuclei prepared from tomato golden mosaic virus (TGMV)-infected Nicotiana benthamiana leaves have been used in in vitro DNA and RNA polymerisation reactions. The synthesis of virus-specific DNA was resistant to aphidicolin, sensitive to N-ethylmaleimide and dideoxy TTP, and stimulated by KCl and ATP. Variably virion (+) and complementary (-) strand DNA of both the A and B genomic components were synthesised. Virus-specific RNA was synthesised in reactions which were initiated prior to nuclei isolation and leaching. From inhibitor studies and salt requirements RNA synthesis appeared to be catalysed by a DNA-dependent RNA polynerase type II enzyme. Both components of the TGMV genome were transcribed in a bidirectional fashion with a prevalence in some experiments of transcripts derived from DNA component A.