TY - JOUR
T1 - Postselection thymocyte maturation and emigration are independent of IL-7 and ERK5
AU - Weinreich, Michael A.
AU - Jameson, Stephen C.
AU - Hogquist, Kristin A.
PY - 2011/2/1
Y1 - 2011/2/1
N2 - The transcription factor Krüppel-like factor 2 (KLF2) controls the emigration of conventional T cells from the thymus through its regulation of the cell surface receptor S1P1. Prior to KLF2 expression, developing T cells require a positive selection signal through the TCR. However, following positive selection there are time, spatial, and maturational events that occur before KLF2 is finally upregulated and emigration occurs. We are interested in determining the signals that upregulate KLF2 and allow thymocytes to emigrate into circulation and whether they are linked to functional maturation. In endothelial cells KLF2 expression has been shown to be dependent on the mitogen-activated protein kinase ERK5. Furthermore, it has been reported that IL-7 signaling leads to the phosphorylation of ERK5. Thus, we hypothesized that IL-7R signaling through ERK5 could drive the expression of KLF2. In this study, we provide evidence that this hypothesis is incorrect. We also found that CD8 lineage specification occurred normally in the absence of IL-7R signaling, in contrast to a recently proposed model. We showed that both CD4 and CD8 T cells complete maturation and express KLF2 independently of ERK5 and IL-7.
AB - The transcription factor Krüppel-like factor 2 (KLF2) controls the emigration of conventional T cells from the thymus through its regulation of the cell surface receptor S1P1. Prior to KLF2 expression, developing T cells require a positive selection signal through the TCR. However, following positive selection there are time, spatial, and maturational events that occur before KLF2 is finally upregulated and emigration occurs. We are interested in determining the signals that upregulate KLF2 and allow thymocytes to emigrate into circulation and whether they are linked to functional maturation. In endothelial cells KLF2 expression has been shown to be dependent on the mitogen-activated protein kinase ERK5. Furthermore, it has been reported that IL-7 signaling leads to the phosphorylation of ERK5. Thus, we hypothesized that IL-7R signaling through ERK5 could drive the expression of KLF2. In this study, we provide evidence that this hypothesis is incorrect. We also found that CD8 lineage specification occurred normally in the absence of IL-7R signaling, in contrast to a recently proposed model. We showed that both CD4 and CD8 T cells complete maturation and express KLF2 independently of ERK5 and IL-7.
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U2 - 10.4049/jimmunol.1002238
DO - 10.4049/jimmunol.1002238
M3 - Article
C2 - 21187442
AN - SCOPUS:79251548902
SN - 0022-1767
VL - 186
SP - 1343
EP - 1347
JO - Journal of Immunology
JF - Journal of Immunology
IS - 3
ER -