title: Creation of a bi-directional protein transduction system for suppression of HIV-1 expression by p27SJ.
abstract: p27SJ is a novel protein from a callus culture of St. John's wort that modulates transcription of the HIV-1 promoter in several mammalian cells [Darbinian-Sarkissian, N., Darbinyan, A., Otte, J., Radhakrishnan, S., Sawaya, B.E., Arzumanyan, A., Chipitsyna, G., Popov, Y., Rappaport, J., Amini, S., Khalili, K., 2006. p27(SJ), a novel protein from St. John's wort, that suppresses expression of HIV-1 genome. Gene Ther. 13, 288-295]. Here, we armed p27SJ with signals from Ig-kappa light chain that allow its efficient excretion from the cells, and from HIV-1 Tat that facilitates its uptake by other cells for its utilization by a protein transduction method. We demonstrate that treatment of cells containing the HIV-1 LTR with conditioned media from cells expressing the armed p27SJ ((exc)p27SJ(upt)) results in suppression of the viral activation by the C/EBPbeta transcription factor. Once imported into the cells, (exc)p27SJ(upt) impacts the nuclear localization of C/EBPbeta and by retaining the protein in the cytoplasm affects its DNA binding and hence transcriptional activity. The armed p27SJ also inhibits Tat-induced activation of the LTR and decreases the level of viral replication in promonocytic cells including U-937 and T-lymphocytic cells. Our observations introduce a new bi-directional protein transduction system with a broad spectrum of applications for manufacturing therapeutic peptides by a specific group of cells called donor, and delivery to the target cells named recipient. Furthermore, our results support the utility of soluble p27SJ in suppressing transcription and replication of HIV-1 by interfering with the function of cellular proteins such as C/EBPbeta and viral activators including Tat.
authors: Department of Neuroscience, Temple University School of Medicine, 1900 North 12th Street, 015-96, Room 203, Philadelphia, PA 19122, United States.
authors: Nune
authors: N
authors: Darbinian
authors: Yuri
authors: Y
authors: Popov
authors: Kamel
authors: K
authors: Khalili
authors: Shohreh
authors: S
authors: Amini
mesh_terms: D019380:Anti-HIV Agents / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D001253:Astrocytes / Q000821:virology; D022782:CCAAT-Enhancer-Binding Protein-beta / Q000037:antagonists & inhibitors; D002460:Cell Line; D002478:Cells, Cultured; D016655:HIV Core Protein p24 / Q000096:biosynthesis; D015497:HIV-1 / Q000187:drug effects*; D006801:Humans; D020902:Hypericum / Q000737:chemistry*; D017628:Microglia / Q000821:virology; D009000:Monocytes / Q000821:virology; D010940:Plant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism* / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000821:virology; D014158:Transcription, Genetic; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000037:antagonists & inhibitors
chemical_list: D019380:Anti-HIV Agents; D022782:CCAAT-Enhancer-Binding Protein-beta; D016655:HIV Core Protein p24; D010940:Plant Proteins; D054322:tat Gene Products, Human Immunodeficiency Virus