Total synthesis of TRADD death domain with arginine N-GlcNAcylation by hydrazide-based native chemical ligation

TNFR1-associated death domain protein(TRADD)with arginine N-GlcNAcylation is a novel and structurally unique posttranslational modification(PTM)glycoprotein that blocks the formation of death-inducing signaling complex(DISC),orchestrating host nuclear factorκB(NF-κB)signaling in entero-pathogenic Escherichia coli(EPEC)-infected cells.This particular glycosylated modification plays an extremely vital role for the effective colonization and pathogenesis of pathogens in the gut.Herein we describe the total synthesis of TRADD death domain(residues 195-312)with arginine235 NGlcNAcylation(Arg-GIcNAc TRADD(195-312)).Two longish peptidyl fragments of the wild-type primary sequence were obtained by robust,microwave-assisted,highly efficient,solid-phase peptide synthesis(SPPS),the N-GlcNAcylated sector was built by total synthesis and attached specifically to resinbound peptide with an unprotected ornithine residue via silver-promoted on-resin guanidinylation,ArgGlcNAc TRADD(195-312)was constructed by hydrazide-based native chemical ligation(NCL).The facile synthetic strategy is expected to be generally applicable for the rapid synthesis of other proteins with Arg-GIcNAc modification and to pave the way for the related chemically biological study.

TRADD介导的信号通路及其与疾病的相关性

肿瘤坏死因子受体相关死亡结构域蛋白(tumor necrosis factor receptor-associated death domain protein, TRADD)是一种细胞内衔接分子,通过肿瘤坏死因子受体1(tumor necrosis factor receptor 1, TNFR1)介导核因子-κB(nuclear factor-κB, NF-κB)和凋亡通路。TRADD由两个功能域构成,即N端TNF受体相关因子(TNF receptor associated factor, TRAF)结合域和C端死亡结构域(death domain, DD)。TRADD-DD可以与同型DD相互作用招募多种具有死亡结构域的下游蛋白,引发不同的下游信号通路从而产生多种功能事件,如细胞凋亡、炎症信号传导等。此外,TRADD信号通路还与许多人类疾病的发生和进展有关。本综述主要介绍TRADD介导的信号通路,特别是NF-κB通路,TRADD介导信号通路的结构基础以及一系列TRADD相关疾病的研究进展。