Cyclin mRNA and protein expression in recombinant interleukin 2-stimulated cloned murine T lymphocytes

✍ Scribed by P. M. Shipman; D. E. Sabath; A. H. Fischer; P. G. Comber; K. Sullivan; E. M. Tan; M. B. Prystowsky

• Publisher: John Wiley and Sons
• Year: 1988
• Tongue: English
• Weight: 614 KB
• Volume: 38
• Category: Article
• ISSN: 0730-2312
• DOI: 10.1002/jcb.240380306

✦ Synopsis

Expression of cyclin, a non-histone nuclear protein, during recombinant interleukin 2 (rIL2)-driven cell-cycle progression of cloned T lymphocytes has been assessed. We found that expression of cyclin protein, as detected by immunofluorescence, is tightly associated with proliferation, and not merely S-phase, of L2 cells stimulated with rIL2. Cyclin immunofluorescence was detected in all cellcycle phases (GI/S/G2/M, as detected by flow cytometry) of proliferating L2 cells. Accumulation of cyclin mRNA levels was induced as early as 1 h after stimulation, was maximal at 25-49 h, and remained elevated throughout stimulation, as detected by Northern blot analysis. A cDNA-encoding murine cyclin was cloned from a cDNA library prepared from IL2-stimulated cloned T cells. The sequence of the 5' end of the murine cyclin cDNA was determined and found to be 88% and 82% similar to the sequences of cDNA clones encoding rat and human cyclin, respectively. The present studies demonstrate that cyclin protein and mRNA accumulation are highly regulated during IL2-induced proliferation of a cloned T cell. These data provide a framework for addressing the molecular mechanisms regulating cyclin gene expression during cellular proliferation.