TY - JOUR
T1 - Conditional knockout of the RNA-binding protein HuR in CD4+ T cells reveals a gene dosage effect on cytokine production
AU - Gubin, Matthew M.
AU - Techasintana, Patsharaporn
AU - Magee, Joseph D.
AU - Dahm, Garrett M.
AU - Calaluce, Robert
AU - Martindale, Jennifer L.
AU - Whitney, Maryln S.
AU - Franklin, Craig L.
AU - Besch-Williford, Cindy
AU - Hollingsworth, John W.
AU - Abdelmohsen, Kotb
AU - Gorospe, Myriam
AU - Atasoy, Ulus
N1 - Funding Information:
This work was supported by National Institutes of Health grants R01AI080870-01 and R21AI079341-01 (to U Atasoy). M Gorospe, K Abdelmohsen and JL Mar-tindale were kindly supported by the National Institute on Aging Intramural Research Program, National Institutes of Health (NIA, IRP, NIH).
PY - 2014
Y1 - 2014
N2 - The posttranscriptional mechanisms by which RNA binding proteins (RBPs) regulate T-cell differentiation and cytokine production in vivo remain unclear. The RBP HuR binds to labile mRNAs, usually leading to increases in mRNA stability and/or translation. Previous work demonstrated that HuR binds to the mRNAs encoding the Th2 transcription factor trans-acting T-cell-specific transcription factor (GATA-3) and Th2 cytokines interleukin (IL)-4 and IL-13, thereby regulating their expression. By using a novel conditional HuR knockout (KO) mouse in which HuR is deleted in activated T cells, we show that Th2-polarized cells from heterozygous HuR conditional (OX40-Cre HuRfl/+) KO mice had decreased steady-state levels of Gata3, Il4 and Il13 mRNAs with little changes at the protein level. Surprisingly, Th2-polarized cells from homozygous HuR conditional (OX40-Cre HuRfl/fl) KO mice showed increased Il2, Il4 and Il13 mRNA and protein via different mechanisms. Specifically, Il4 was transcriptionally upregulated in HuR KO T cells, whereas Il2 and Il13 mRNA stabilities increased. Additionally, when using the standard ovalbumin model of allergic airway inflammation, HuR conditional KO mice mounted a robust inflammatory response similar to mice with wild-type HuR levels. These results reveal a complex differential posttranscriptional regulation of cytokines by HuR in which gene dosage plays an important role. These findings may have significant implications in allergies and asthma, as well as autoimmune diseases and infection.
AB - The posttranscriptional mechanisms by which RNA binding proteins (RBPs) regulate T-cell differentiation and cytokine production in vivo remain unclear. The RBP HuR binds to labile mRNAs, usually leading to increases in mRNA stability and/or translation. Previous work demonstrated that HuR binds to the mRNAs encoding the Th2 transcription factor trans-acting T-cell-specific transcription factor (GATA-3) and Th2 cytokines interleukin (IL)-4 and IL-13, thereby regulating their expression. By using a novel conditional HuR knockout (KO) mouse in which HuR is deleted in activated T cells, we show that Th2-polarized cells from heterozygous HuR conditional (OX40-Cre HuRfl/+) KO mice had decreased steady-state levels of Gata3, Il4 and Il13 mRNAs with little changes at the protein level. Surprisingly, Th2-polarized cells from homozygous HuR conditional (OX40-Cre HuRfl/fl) KO mice showed increased Il2, Il4 and Il13 mRNA and protein via different mechanisms. Specifically, Il4 was transcriptionally upregulated in HuR KO T cells, whereas Il2 and Il13 mRNA stabilities increased. Additionally, when using the standard ovalbumin model of allergic airway inflammation, HuR conditional KO mice mounted a robust inflammatory response similar to mice with wild-type HuR levels. These results reveal a complex differential posttranscriptional regulation of cytokines by HuR in which gene dosage plays an important role. These findings may have significant implications in allergies and asthma, as well as autoimmune diseases and infection.
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U2 - 10.2119/molmed.2013.00127
DO - 10.2119/molmed.2013.00127
M3 - Article
C2 - 24477678
AN - SCOPUS:84897857258
SN - 1076-1551
VL - 20
SP - 93
EP - 108
JO - Molecular Medicine
JF - Molecular Medicine
IS - 1
ER -