Tat lysine mutants are expressed at different levels in cells.

<p>(A) 293T cells were transfected with various GFP-Tat plasmids or the empty vector, and the fluorescence of GFP was examined by fluorescence microscopy 24 hours after transfection. (B) Experiments were performed as in panel A, and the expression levels of the GFP fusion proteins were measured via the ImageJ software and normalized to the vector group. WT, wild-type; ND, not determined.