The N-CTD nucleic acid-binding domain may also transactivate other viruses containing TAR-like sequences, similar to the lentiviral Tat-binding domains to TAR and, as exemplified by the transactivation of JCV, by HIV-1 Tat leading to the development of progressive multifocal leukoencephalopathy. The gene discussed is RBM8A; the disease is progressive multifocal leukoencephalopathy.