Empty Turnip yellow mosaic virus capsids as delivery vehicles to mammalian cells.

•Turnip yellow mosaic virus (TYMV) conjugated with Tat enters cells efficiently.•Tat-assisted transfection was more efficient and less harmful than lipofection.•TYMV particles can be made empty through a freezing and thawing process.•Empty TYMV can be internally loaded with fluorescein using interior Cys residues.•Fluorescein-loaded TYMV efficiently enters BHK cells when conjugated with Tat.