Progress Advance on Biological Functions of LPS-induced TNF-α

Abstract: LPS-induced TNF-α (LITAF)， also known as p53-inducible gene 7 (PIG7) or small integral membrane protein of the lysosome/late endosome (SIMPLE)， was initially demonstrated to be negatively regulated by p53 through specific binding to a heptamer (from 164 aa to 170 aa) in an LPS-stimulated human monocytes. Subsequent studies conformed that LITAF served as a transcriptional activator of inflammatory cytokine TNF-α towards LPS exposed monocytes or macrophages. The typical LITAF contains the N-terminal CXXC motif， followed by the hydrophobic region of 25 amino acids residues and the C-terminal (H)XCXXC knuckle. Two CXXC motifs will bind together and form a compact Zn2+-binding structure in response to LPS exposure. The LITAF then enters into nucleus through recruiting STAT6(B) and subsequently induces TNF-α transcription by binding its promotor region. In this review， recent progress on LITAF structure and its biological function were summarized.

CSTR: 32200.14.cjcb.2015.04.0015