p17 and p17-containing gag precursors of input human immunodeficiency virus are transported into the nuclei of infected cells.

Subcellular localization of input human immunodeficiency virus type 1 (HIV-1) gag proteins was determined in infected H9 and Jurkat tat cells. Infected cells were fractionated at intervals, and the proteins in cell fraction were identified by immunoblotting using pooled sera from acquired immunodeficiency syndrome (AIDS) patients and monoclonal antibodies. Cycloheximide was added at 0 time to prove that the proteins detected were not nascent ones. Gag proteins p55, p41, p39 (in the most essential relative concentrations), and p17 were found in the cell nuclei for at least 4 h after infection. However, p24 was not found in the cell nuclei and was accumulated in the nuclear washing buffer. The data presented confirm the presence of karyotypic signal at the N terminus of p55 gag precursor. The potential role of nuclear localization of gag precursor is discussed.