Expression of a novel nuclear protein in activated and in tat-I expressing T cells

• Published in: The Journal of immunology (1950) Vol. 146; no. 3; pp. 1031 - 1036
• Main Authors: Bielinska, A, Baier, L, Hailat, N, Strahler, JR, Nabel, GJ, Hanash, S
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Am Assoc Immnol 01-02-1991; American Association of Immunologists
• Subjects: Analytical, structural and metabolic biochemistry; Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Genes, tat; Holoproteins; human immunodeficiency virus 1; Humans; Lymphocyte Activation; Nuclear proteins; Nuclear Proteins - analysis; Phosphoproteins - analysis; Proteins; T-Lymphocytes - chemistry; T-Lymphocytes - immunology; Tetradecanoylphorbol Acetate - pharmacology; Transfection; Cell culture; Lymphoid cell; HIV-1 virus; Molecular weight determination; Gel electrophoresis; Retroviridae; Identification; In vitro; Lymphoma; Virus; Cell line; Transfection; Isoelectric point; T-Lymphocyte; Lentivirinae; Human immunodeficiency virus; Nuclear protein
• ISSN: 0022-1767; 1550-6606
• DOI: 10.4049/jimmunol.146.3.1031

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.