TAT and viral infectious disease: RSK2 has been implicated in other viral infections, such as HIV, HCV, and influenza.15, 16 Kaposi's sarcoma‐associated herpes virus ORF45 mediates transcriptional activation of the HIV‐1 long terminal repeat via RSK2.17, 18, 19 HIV Tat protein interacts with RSK2 and activated RSK2 kinase activity in cells, and might serve to induce early changes in the chromatin organization of the HIV LTR.20 The regulation and function of RSK2 may explain its role in HBx enhancement of HBV replication.