0000000000348976
AUTHOR
Christian Jassoy
Activation of cGMP-dependent Protein Kinase Iβ Inhibits Interleukin 2 Release and Proliferation of T Cell Receptor-stimulated Human Peripheral T Cells
Several major functions of type I cGMP-dependent protein kinase (cGK I) have been established in smooth muscle cells, platelets, endothelial cells, and cardiac myocytes. Here we demonstrate that cGK Ibeta is endogenously expressed in freshly purified human peripheral blood T lymphocytes and inhibits their proliferation and interleukin 2 release. Incubation of human T cells with the NO donor, sodium nitroprusside, or the membrane-permeant cGMP analogs PET-cGMP and 8-pCPT-cGMP, activated cGK I and produced (i) a distinct pattern of phosphorylation of vasodilator-stimulated phosphoprotein, (ii) stimulation of the mitogen-activated protein kinases ERK1/2 and p38 kinase, and, upon anti-CD3 stimu…
NFAT transcription factors control HIV-1 expression through a binding site downstream of TAR region.
NFAT factors control HIV-1 transcription. We show here that, in addition to binding to two NF-kappaB/NFAT sites within the U3 HIV LTR, NFATc1 and NFATc2 bind to an NFAT site within the LTR's U5 region. Mutations in this site which abolish NFAT binding reduce the ability of NFATs to transactivate LTR-mediated transcription. Mutations in all three NFAT sites strongly interfered with LTR induction, but affected moderately the stimulatory effect of Tat.