Cassandra M Joiner, Tiarra J Glogowski, Erin M NewRingeisen, Huy V Huynh, Melanie G Roberts, Madison M Rognerud, Hahns E Huebsch
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引用次数: 0
Abstract
O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) is an essential, stress-sensing enzyme responsible for adding the O-GlcNAc monosaccharide to thousands of nuclear and cytoplasmic proteins to regulate cellular homeostasis. OGT substrates are found in almost all intracellular processes, and perturbations in protein O-GlcNAc levels have been implicated in proteostatic diseases, such as cancers, metabolic disorders, and neurodegeneration. This broad disease activity makes OGT an attractive therapeutic target; however, the substrate diversity makes pan-inhibition as a therapeutic strategy unfeasible. Rather, a substrate-specific approach to targeting is more advantageous, but how OGT chooses its substrates remains poorly understood. Substrate specificity is controlled by the interactions between OGT's non-catalytic tetratricopeptide repeat (TPR) domain, rather than its glycosyltransferase domain. OGT's TPR domain forms a 100 Å superhelical structure, containing a lumenal surface, known as the substrate-binding surface, and a solvent-exposed surface. To date, there are no tools to site-selectively target regions of the domain and differentiate between the two binding surfaces. Here, we developed a library of recombinant OGT constructs containing site-specifically incorporated photoactivatable unnatural amino acids (UAAs) along the solvent-exposed surface of the TPR domain to covalently capture and map OGT's interactome.
期刊介绍:
ChemBioChem (Impact Factor 2018: 2.641) publishes important breakthroughs across all areas at the interface of chemistry and biology, including the fields of chemical biology, bioorganic chemistry, bioinorganic chemistry, synthetic biology, biocatalysis, bionanotechnology, and biomaterials. It is published on behalf of Chemistry Europe, an association of 16 European chemical societies, and supported by the Asian Chemical Editorial Society (ACES).