Purification and serology of virions of impatiens necrotic spot tospovirus

Impatiens necrotic spot tospovirus (INSV) virions were purified using a procedure devised for tomato spotted wilt tospovirus (TSWV) from systemically infected Nicotiana benthamiana plants grown at 33 degree C day/26 degree C night and a photoperiod of 14 hours. With plants grown at 24/18 degree C purification was unsuccessful. In SDS-PAGE the protein pattern of INSV was similar to that reported for TSWV, except the appearance of a single G2 protein band. A polyclonal antiserum, prepared against virions, reacted in Western blots with INSV nucleoprotein and glycoproteins but only with TSWV glycoproteins. In DAS ELISA the antiserum reacted with both INSV and TSWV infected plant sap and, after absorption with TSWV, only with INSV. In TAS ELISA the antiserum trapped both INSV and TSWV nucleoproteins and glycoproteins as detected by specific monoclonal antibodies, and, after absorption with TSWV, only the homologous proteins. This appears to be the first report of the purification of INSV virions and the production of an antiserum reacting with both nucleoprotein and glycoprotein antigens.