Constitutive Expression of Human Ribosomal Protein L7 Arrests the Cell Cycle in G1and Induces Apoptosis in Jurkat T-Lymphoma Cells

doi:10.1006/excr.1996.3417

Experimental Cell Research

Volume 230, Issue 2, 1 February 1997, Pages 252-261

https://doi.org/10.1006/excr.1996.3417 Get rights and content

Abstract

Protein L7 is involved in translational control in eucaryotic cells as indicated by its association with ribosomes, its capability to inhibit specifically the cell-free translation of distinct mRNAs, and its interference with the synthesis of two major nucleus-associated proteins in L7 cDNA-transfected Jurkat T-lymphoma cells [F. Neumannet al.(1995)Nucleic Acids Res.23, 195]. In this report we show that the constitutive expression of protein L7 in Jurkat cells leads to an arrest in G₁of the cell cycle and induces apoptosis as a consequence of cell-to-cell contact. Treatment of the L7 transfectants with the inhibitor of translation cycloheximide, at doses which do not affect untransfected cells, enhances their sensitivity to the induction of apoptosis. These results suggest that L7 can interfere with the translation of proteins which control cell cycle progression and/or the initiation of the apoptotic pathway.

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¹: To whom correspondence and reprint requests should be addressed at Faculty of Biology, University of Konstanz, P.O. Box 5560M661, D-78434 Konstanz, Germany. Fax: -49-7531-883102. E-mail: [email protected].

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Regular ArticleConstitutive Expression of Human Ribosomal Protein L7 Arrests the Cell Cycle in G1and Induces Apoptosis in Jurkat T-Lymphoma Cells

Abstract

Regular Article
Constitutive Expression of Human Ribosomal Protein L7 Arrests the Cell Cycle in G₁and Induces Apoptosis in Jurkat T-Lymphoma Cells