Frazier-Jessen Michelle R, Thompson Cynthia D, Brown Robert, Rawat Rashmi, Nordan Richard P, Feldman Gerald M
Laboratory of Immunobiology, Division of Monoclonal Antibodies, Office of Therapeutics Research and Review, Center for Biologics Evaluation and Research, Food and Drug Administration, Bethesda, MD 20892, USA.
FEBS Lett. 2002 Feb 27;513(2-3):203-7. doi: 10.1016/s0014-5793(02)02295-0.
Macrophages respond to bacterial lipopolysaccharide (LPS) by activating latent cis-acting factors that initiate transcription of immediate early genes. One such immediate early gene, junB, is induced by LPS in macrophages within 30 min. To identify elements that mediate the induction of junB by LPS, upstream and downstream sequences flanking the junB gene were examined by transient expression in the RAW264.7 murine macrophage cell line using a luciferase reporter gene vector containing the junB minimal promoter. A >10-fold enhancement was associated with a 222 bp region downstream of the junB promoter in response to LPS. Transient reporter assays demonstrated that multiple nuclear factor (NF) kappaB sites are required for inducibility of junB by LPS in RAW264.7 cells. Electrophoretic mobility shift assays confirmed binding of LPS-induced nuclear proteins included p50/p65 heterodimers at these NF-kappaB sites.
