Fig. 1

Model of possible TLR4-miR-155 positive feedback loop. LPS-activated TLR4 signaling might promote the transcription of pri-miR-155 by triggering transcription factors such as NF-kB, AP-1, Ets2, and might enhance the maturation of miR-155 through a post-transcriptional mechanism depending on the induction of KSRP. These events might result in the overexpression of miR-155. The high level of expressed miR-155 might target SOCS1 and SHIP1, two key negative regulators of TLR4 signaling, thereby promoting the expression of TLR4, and ultimately constituted a TLR4-miR-155 positive feedback loop