We observed a significant increase, after endotoxin stimulation at 4 hours, in the mRNA levels of IL 1 receptor associated kinase 2 which regu lates phosphorylation and the genes that are involved in ubiquitination, ubiquitin conjugating enzyme E2Q family member 2, ubiquitin protein ligase E3C, ubiquitin selleckchem Belinostat conjugating enzyme E2A, ubiquitin conjugating enzyme E2, J1, ubiqui tination factor E4B. Because the number of dif ferentially expressed genes increased with time up to 4 hps, we were able to define more precise interactions at that time among the analyzed genes using the Ingenuity Pathway Analysis software IL1 receptor family members, IL1RL2 and IL1R2 were responsive to 4 hours of endotoxin stimulation relative to untreated cells.

We conclude that IL1B is a central node in the cellular response network due to its coordination and interactions with other molecules in the network. The functions of all genes demonstrated in the net works at all time points are indicated in additional file 2. s upon exposure to endotoxin Fold changes in the DE genes ranged from 1. 68 1 to 5. 65 at all time points, but q values were highly significant. We did not detect a signifi cant increase in mRNA level of any TLR during the course of exposure, however, TLR2 was significantly down regulated at 4 hps. Interestingly, NLRC5, an intracellular receptor, in HD11 cells treated with endotoxin for 4 hours was induced in the present study. Similar to TLRs, the NLRs recognize pathogen associated molecular patterns that are expressed by bacteria and then activate translocation of NF B from the cytosol to the nucleus.

NLRC5 was responsive to endotoxin, however it was not included in either gene networks or functional groups. Despite accumulating research data, the exact molecular mechanism of NLR activation and the initia tion of signaling cascades in mammals are not yet fully defined. The data of the present study, however, clearly identify a role for NLRC5 in chicken macrophage response to endotoxin. Discussion We did not detect any significant up regulation in the mRNA levels of TLR3, TLR4, TLR5, TLR6, TLR7, TLR15, LOC768669 TLR16 TLR6 in the microarray results of this study. Only TLR2 showed a significant change in the mRNA level and was slightly, but significantly, down regulated in stimulated cells. In contrast, NLRC5, was signifi cantly up regulated.

The downregulation of TLR2 might be considered as a result of NLRC5 activation after endotoxin stimulation. The inhibitory effects of NLRC5 on inflammatory pathways have recently been reported. Chicken Tumor Necrosis Factor alpha gene has not been identified in the chicken genome yet. Interest ingly, our study reports differential expression of three TNFalpha related genes after AV-951 1 hour endotoxin expo sure, including TNFAIP3, TNIP2, and TRAF3 genes, thus providing additional evidence of existence of genes with TNFA function in chickens.