RNA processing is a limiting step for murine tumor necrosis factor beta expression in response to interleukin-2.
We have previously reported that tumor necrosis factor beta (TNF beta) expression is induced by interleukin-2 (IL-2) in the murine lymphocytic T-cell line CTLL-2. In this study, we have characterized the nuclear and cytoplasmic TNF beta transcript and assessed their role in TNF beta gene expression. A unique feature of TNF beta expression was the accumulation of nuclear precursors, which reflected a slow nuclear RNA processing. As a consequence, there was a delay in the appearance of cytoplasmic messengers after the transcriptional induction of TNF beta by IL-2. We also found that two messengers, the fully spliced messenger and an intron 3-retaining messenger, were exported to the cytoplasm and actively translated. The same pattern of expression was observed in concanavalin A-stimulated splenocytes, although the level of expression was much lower than in CTLL-2 cells. The simple genetic structure and the high level of accumulation of nuclear precursors make TNF beta a particularly attractive model system to use for studies of RNA processing and cytoplasmic transport of partially spliced messengers.
Weil
D
D
Laboratoire d'Oncologie Moléculaire, Institut Gustave Roussy, Centre National de la Recherche Scientifique UA 1158, Villejuif, France.
Brosset
S
S
Dautry
F
F
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D003208:Concanavalin A / Q000494:pharmacology; D003593:Cytoplasm / Q000378:metabolism; D005091:Exons; D015723:Gene Library; D007376:Interleukin-2 / Q000494:pharmacology*; D007438:Introns; D008213:Lymphocyte Activation; D008233:Lymphotoxin-alpha / Q000235:genetics*; D051379:Mice; D008807:Mice, Inbred BALB C; D008969:Molecular Sequence Data; D014176:Protein Biosynthesis; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D012333:RNA, Messenger / Q000235:genetics* / Q000378:metabolism; D013602:T-Lymphocytes, Cytotoxic; D014158:Transcription, Genetic
D007376:Interleukin-2; D008233:Lymphotoxin-alpha; D012333:RNA, Messenger; D003208:Concanavalin A; D012313:RNA