Expression of serum- and glucocorticoid-regulated kinase (sgk) mRNA is up-regulated by GM-CSF and other proinflammatory mediators in human granulocytes
Rt. Cowling et Hc. Birnboim, Expression of serum- and glucocorticoid-regulated kinase (sgk) mRNA is up-regulated by GM-CSF and other proinflammatory mediators in human granulocytes, J LEUK BIOL, 67(2), 2000, pp. 240-248
Stimulation of human peripheral blood granulocytes with the proinflammatory
cytokine, granulocyte-macrophage colony-stimulating factor (GM-CSF), incre
ases incorporation of [H-3]uridine into RNA. We investigated the nature of
the RNA synthesized under these conditions, Using transcription inhibitors,
gel electrophoresis, and high-salt precipitation, it was concluded that as
much as 90% of this radiolabeled RNA represents polymerase II transcripts,
Differential display reverse transcription-polymerase chain reaction tvas
used to identify and clone GM-CSF-responsive mRNAs. Serum- and glucocortico
id-regulated kinase (sgk) mRNA was identified that could be up-regulated 10
- to 20-fold by greater than or equal to 0.1 ng/mL recombinant human GM-CSF
. The 2.6-kb sgk mRNA was induced rapidly (within 30 min) by GM-CSF and rem
ained at high levels for at least 12 h, Up-regulation was blocked completel
y by the transcription inhibitor, actinomycin D, but not by the translation
inhibitor, cycloheximide, nor by the tyrosine kinase inhibitor, genistein,
Up-regulation did not appear to be caused by enhanced mRNA stability, Othe
r inflammatory mediators could also increase sgk mRNA levels (GM-CSF >> lip
opolysaccharide > fMLP = tumor necrosis factor alpha), The function of sgk
in granulocytes remains unknown.