Fig. 1.

Expression of Nullbasic-mCherry (NB-mCh) and mCherry (mCh) in TZM-bl cells. a A schematic of the NB-mCh amino acid sequence. The basic domain of wild type Tat was mutated to glycine or alanine residues as shown (green) and other domains are labeled. b A schematic diagram of SIN γ-retroviral SRS11-SF-γC vector showing NB-mCh or mCh that are expressed by a SFFV internal promoter. Rous Sarcoma Virus (RSV) promoter is used to transcribe mRNA for packaging in VLPs. The woodchuck hepatitis virus post transcription regulatory element (WPRE) was inserted adjacent to NB-mCh or mCh to enhance gene expression. c Purity of selected TZM-bl cells expressing NB-mCh or mCh analyzed by flow cytometry. d NB-mCh and mCh expression in TZM-bl cells was detected by a Western Blot using anti-mCherry antibody. The blot was also stained with an anti-β tubulin antibody