The roles of lipopolysaccharide receptor cluster and large-conductance Ca2 ＋-activated potassium channel in the iipopolysaccharide recognition

Abstract

Background Bacterial lipopolysaecharide（LPS） induces eytokine synthesis and secretion in cells, subsequently resulting in systemic inflammatory response. The LPS receptor recognition and transmembrane signal transduction play a key role in LPS-induced cell activation. Objective To review a novel theory of LPS receptor activation cluster and the role of large- conductance Ca2＋-activated potassium channel （MaxiK） in LPS recognition. Content Following ligation of CD14 by LPS, different signaling molecules are recruited at the site of the ligation within lipid rafts, where LPS is then briefly released into the lipid bilayer and finally interacts with a complex of receptors. Depending on the cell type and the bacterial stimulus, different LPS receptor clusters can be formed. The activation of the MaxiK channel is an early step in LPS-induced transmembrane signal transduction in macrophages. And the central IKB-~/NF-KB-dependent proinflammatory pathway depends on the function of MaxiK channel in macrophages. Trend The molecular mechanism of LPS receptor recruitment to specific membrane domains is not well understood. The signaling complex appears to recruit several accessory proteins with yet mostly unknown functions for the process of stimulus recognition and signal transduction, Key words: Lipopolysaccharide ; Lipopolysaccharide receptor; Protein-protein interaction ; The large-conductance Ca2＋-activated potassium channel