Purification and characterization of turnip mosaic virus helper component protein

• Published in: Phytopathology Vol. 89; no. 7; pp. 564 - 567
• Main Authors: Wang, R.Y, Pirone, T.P
• Format: Journal Article
• Language: English
• Published: St. Paul, MN American Phytopathological Society 01.07.1999
• Subjects: Biological and medical sciences; Brassica rapa subsp. rapa; disease transmission; disease vectors; Fundamental and applied biological sciences. Psychology; insect pests; Lipaphis erysimi; Myzus persicae; Phytopathology. Animal pests. Plant and forest protection; Plant viruses and viroids; protein composition; purification; Systematics. Structure, properties and multiplication. Genetics; Turnip mosaic virus; viral proteins; Virus; Purification; Plant pathogen; Molecular weight determination; Turnip mosaic virus; Transmission; Molecular interaction; Species specificity; Potyvirus; Vector; Helper component; Potyviridae
• ISSN: 0031-949X; 1943-7684
• DOI: 10.1094/PHYTO.1999.89.7.564

The helper component (HC) protein of turnip mosaic virus (TuMV) was concentrated by differential centrifugation followed by ammonium sulfate precipitation. The partially purified HC was then loaded onto a Ni2(+)-resin column that bound the HC; a histidine tag was not required for binding. The HC eluted from the column migrated as a band of about 50 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In its native state, the HC did not pass through an ultrafiltration membrane with a molecular mass cutoff of 100 kDa, which suggested that the HC is in a multimeric form when it is biologically active. The molecular mass of the multimeric form was determined by gel filtration to be approximately 145 kDa. Purified HC retained its activity for several months at -20 degrees C. Using a protein blotting-overlay protocol, purified HC interacted in vitro with an aphid-transmissible TuMV isolate, but not with a non-aphid-transmissible isolate.