TAT and AIDS: Sun et al. explored the effects of the human immmunodeficiency virus-1/acquired immunodeficency syndrome (HIV-1/AIDS) trans-activator of transcription (Tat) protein on human rhabdomyosarcoma cellular responses to ionizing radiation and found that HIV-1 Tat protein sensitizes cells to ionizing radiation via depressing DNA repair and dysregulating cell cycle checkpoints27.