Novel roles for GlcNAc in cell signaling

Abstract

N-acetylglucosamine (GlcNAc) has long been known to play important roles in cell surface structure. Recent studies are now revealing new functions for GlcNAc in cell signaling. Exposure to GlcNAc regulates virulence functions in the human fungal pathogen Candida albicans and in pathogenic bacteria. These signaling pathways sense exogenous GlcNAc and are distinct from the O-GlcNAc signaling pathways in mammalian cells in which increased levels of intracellular GlcNAc synthesis leads to post-translational modification of proteins by attachment of O-GlcNAc. The novel roles of GlcNAc in cell signaling will be the subject of this mini-review.

Keywords: Candida albicans; GlcNAc; N-acetylglucosaminen; O-GlcNAc; cell wall; chitin; peptidoglycan.

Figure 1. Models for GlcNAc induction of cell signaling. Note that (A) C. albicans and (B) bacteria such as E. coli are thought to sense forms of GlcNAc that are not synthesized in the cell. Endogenous GlcNAc synthesis pathways are shown in gray.