IADR Abstract Archives

cJun/ATF2 bound promoters in THP1-monocytes and macrophage-like-cells following LPS stimulation

Objectives: Periodontal inflammation involves multi-cellular processes of considerable medical impact, and improved methods of intervention are needed. Promoter arrays have been used to examine response of human THP-1-monocytes and their differentiated macrophage-like-cells (MLC) in response to E. coli lipopolysaccharide (EC-LPS).

Methods: We have developed “promoter-arrays” containing 10,012 human promoter sequences. LPS treatment of THP-1 or MLCs led to activation of N-terminal Jun Kinase (JNK) pathway and increased phosphorylation of JNK and transcription factor substrates c-Jun and ATF2. We compared promoter binding profiles of THP-1 cells and MLCs following stimulation with EC-LPS by a modified ChIP-on-chip protocol using antibodies to the phosphorylated forms of c-Jun and ATF2. Promoters bound by either phosphorylated-c-Jun or phosphorylated-ATF2 were identified by hybridization to promoter arrays in a replicate format leading to 12 independent measurements. Significant promoter hybridization was identified by application of triple statistical criteria including fold-change, p-value and B-value (1).

Results: Stimulation of THP-1 led to large-scale gene binding including 204 phosphorylated-c-Jun bound promoters and 145 phosphorylated-ATF2 bound genes whereas for MLCs 153 phosphorylated-c-Jun bound promoters and 262 phosphorylated-ATF2 bound genes. Of these 124 phosphorylated-c-Jun and 123 phosphorylated-ATF2 bound promoters were common to two LPS-treated-cell-lines indicated that LPS-activation-specific response of MLCs involves 29 phosphorylated-c-Jun and 139 phosphorylated-ATF2 bound genes. Examination of functional classes of bound genes revealed that phosphorylated-ATF2 bound immune response genes including IL1R1, CD1B, CD93, CD40L, EPHB1, IL17C, MMP9, TRAF6, and others. Phosphorylated-c-Jun bound promoters associated with cell-to-cell signaling including IL1R1, FGF19, NOS1, EPHB1, HADH, NGTX, PDE6, and others. We are currently validating the promoter array results and examining effects of promoter binding on expression.

Conclusion: IL-1 and TNFalpha interacting genes such as TRAF6, MMP9, ILR1, EPHB1 may play roles in recruiting and activating other cell partners such as gingival fibroblasts. (1) Hayakawa et al. Mol. Cell 2004, 16: 1-20. NIH/CA 114810.


IADR/AADR/CADR General Session
2007 IADR/AADR/CADR General Session (New Orleans, Louisiana)
New Orleans, Louisiana
2007
66
Microbiology / Immunology and Infection Control
  • Vardar-sengul, Saynur  ( University of California, Irvine, Irvine, CA, USA )
  • Arora, Shilpi  ( University of California, Irvine, Irvine, CA, USA )
  • Wang, Yipeng  ( Sidney Kimmel Cancer Center, San Diego, CA, USA )
  • Baylas, Haluk  ( Ege University, Izmir, N/A, Turkey )
  • Mcclelland, Michael  ( Sidney Kimmel Cancer Center, San Diego, CA, USA )
  • Adamson, Eileen  ( University of California, Irvine, Irvine, CA, USA )
  • Mercola, Dan  ( University of California, Irvine, Irvine, CA, USA )
    • Oral Session
    Immunology
    03/21/2007