R. Goethe et L. Phivan, EVIDENCE FOR AN ENHANCED TRANSCRIPTION-DEPENDENT DE-NOVO SYNTHESIS OFC EBP-BETA IN THE LPS ACTIVATION OF THE CHICKEN LYSOZYME GENE/, Journal of leukocyte biology, 61(3), 1997, pp. 367-374
C/EBP beta has been shown to mediate the lipopolysaccharide (LPS)-indu
ced expression of the lysozyme gene through enhanced binding to the -6
.1-kb lysozyme enhancer. In this study, we describe the LPS regulation
of the C/EBP beta gene in myelomonocytic HD11 cells. Northern analysi
s showed that the steady state level of C/EBP beta mRNA increased in r
esponse to LPS. The half life of C/EBP beta mRNA of about 1 h in HD11
cells was not affected by exposure to LPS, Nuclear run-on transcriptio
n experiments with isolated nuclei revealed that the rate of C/EBP bet
a gene transcription was enhanced by LPS, demonstrating that the C/EBP
beta gene in BD11 cells was regulated at the transcriptional level in
response to LPS, Furthermore, the LPS-induced binding activity of C/E
BP beta to the -6.1-kb lysozyme enhancer was dependent not only on pro
tein synthesis, but also on transcription. Thus, these results suggest
ed that the LPS-induced binding activity to the -6,1-kb lysozyme enhan
cer in HD11 cells was regulated by an enhanced transcription-dependent
de novo synthesis of C/EBP beta.