Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Molecular weight and serological comparisons of capsid proteins of grapevine virus A and a grapevine corky bark-associated virus.

Abstract

Closterovirus-like particles (CVLPs) of <800 nm long were purified from 2 grape cultivars affected with grapevine corky bark disease. Their capsid proteins were compared with those of 3 isolates of grapevine virus A [grapevine stem pitting associated closterovirus, GSPAV] from leafroll-affected grape cultivars. The MW of the capsid proteins of the CVLPs from the corky bark-affected cultivars was determined by SDS-PAGE and silver staining to be 25.7 kDa, compared with 27 kDa for the GSPAV capsid proteins. The capsid proteins were also serologically different in Western analysis. Rabbit anti-GVA serum detected the capsid proteins of all 3 isolates of GSPAV, but did not detect the capsid proteins of either corky bark-associated CVLP isolate. Conversely, antiserum prepared against 1 of the corky bark-associated CVLP isolates detected the capsid proteins of both corky bark-associated isolates, but did not detect the capsid proteins of any of the GSPAV isolates. The capsid proteins could be detected in extracts from infected grape tissues by Western analysis performed with the appropriate antiserum.