It is well established that during the early stages of infections, the proteins Tat, Rev, and Nef, encoded by the 1.8 kb intron-less mRNAs, are transported to the cytosol to facilitate the transition from early to late phases of infection, by enhancing transcription transactivation, nuclear export, and translation of the 4 kb and 9 kb mRNAs. Here, TAT is linked to infection.