The age-related decline in the induction of IL-2 transcription is correlated to changes in the transcription factor NFAT.
The effect of aging on the induction of IL-2 transcription by concanavalin A was studied in spleen lymphocytes isolated from young (4-6 months) and old (24 months) male Fischer 344 rats. The induction of IL-2 mRNA levels and IL-2 transcription were 40 to 50% lower for spleen lymphocytes isolated from old rats compared to spleen lymphocytes isolated from young rats. Because the transcription factor NFAT (nuclear factor activating IL-2 transcription) plays a major role in the regulation of IL-2 transcription, the DNA binding activity of NFAT in nuclear extracts of concanavalin A-stimulated lymphocytes was measured using a gel shift assay. The ability of nuclear extracts isolated from either total spleen lymphocytes or T cells to bind the NFAT oligonucleotide decreased 50 to 60% with age. Therefore, the age-related decrease in the expression of IL-2 appears to occur at the level of transcription and involves the transcription factor NFAT.
Pahlavani
M A
MA
Geriatric Research Education and Clinical Center, Audie L. Murphy Memorial Veterans Hospital, San Antonio, Texas, USA.
Harris
M D
MD
Richardson
A
A
D000375:Aging / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000378:metabolism*; D007376:Interleukin-2 / Q000096:biosynthesis / Q000235:genetics*; D008297:Male; D008969:Molecular Sequence Data; D050778:NFATC Transcription Factors; D009687:Nuclear Proteins; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011916:Rats, Inbred F344; D013154:Spleen / Q000166:cytology; D013601:T-Lymphocytes / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic
D004268:DNA-Binding Proteins; D007376:Interleukin-2; D050778:NFATC Transcription Factors; D009687:Nuclear Proteins; D012333:RNA, Messenger; D014157:Transcription Factors