Production of ribosome components in effector CD4+ T cells is accelerated by TCR stimulation and coordinated by ERK-MAPK.
Effector CD4+ T cells rapidly activate high-level cytokine expression following TCR stimulation. Consistent with accelerated protein production in these cells, global mRNA profiles revealed that, after cytokines, the most impressive cluster of activated genes encode rRNA-maturation factors. Activation of these genes was ERK-MAPK dependent, accompanied by increased rRNA transcription and faster maturation kinetics, and much greater in effector CD4+ T cells than in naive cells. Ribosomal protein subunit (RPS) synthesis was also ERK-MAPK dependent and increased to match rRNA production, but without evident increase in RPS mRNA. Instead, stimulation promoted polysome loading of RPS mRNA via cis-acting, 5'-terminal oligopyrimidines. These results demonstrate how, in response to extracellular signals, effector CD4+ T cells coordinately increase multiple ribosomal components to accommodate burgeoning cytokine production.
Asmal
Mohammed
M
Department of Microbiology, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York, NY 10032, USA.
Colgan
John
J
Naef
Felix
F
Yu
Bin
B
Lee
Youngnam
Y
Magnasco
Marcelo
M
Luban
Jeremy
J
D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism*; D051379:Mice; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009687:Nuclear Proteins / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional / Q000502:physiology; D016337:RNA, Catalytic / Q000096:biosynthesis*; D012335:RNA, Ribosomal / Q000378:metabolism
D009687:Nuclear Proteins; D011506:Proteins; D016337:RNA, Catalytic; D012335:RNA, Ribosomal; D020928:Mitogen-Activated Protein Kinases