Expression of a novel nuclear protein in activated and in tat-I expressing T cells.
The intracellular events that occur in T lymphoid cells after activation or after infection with HIV-1 are not well defined. In the case of HIV-1 infection, it is unknown whether the tat-I gene, an essential gene for viral replication, affects host cell nuclear factors. Using two-dimensional PAGE, we have identified a novel nuclear protein, designated nuclear protein-28,000 (NP-28), which is induced in Jurkat T cells by stimulation with PMA and/or PHA or ionomycin. This nuclear protein has an apparent molecular mass of 28,000 Da and an isoelectric point of 4.6. Interestingly, Jurkat cells transfected with tat-I express higher levels of NP-28 constitutively, without added stimulation. Incubation of Jurkat cells expressing tat-I with PMA and/or PHA or ionomycin causes superinduction of NP-28. We have therefore identified a novel lymphoid nuclear protein induced by T cell activation that occurs in tat-I expressing cells in the absence of activating agents.
Bielinska
A
A
Howard Hughes Medical Institute, Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109.
Baier
L
L
Hailat
N
N
Strahler
J R
JR
Nabel
G J
GJ
Hanash
S
S
D015756:Genes, tat; D006801:Humans; D008213:Lymphocyte Activation; D009687:Nuclear Proteins / Q000032:analysis*; D010750:Phosphoproteins / Q000032:analysis; D013601:T-Lymphocytes / Q000737:chemistry* / Q000276:immunology; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D014162:Transfection
D009687:Nuclear Proteins; D010750:Phosphoproteins; D013755:Tetradecanoylphorbol Acetate