Cysteine and Cysteine-Related SignalingPathways in Arabidopsis thaliana  

出　　处：《Molecular Plant》2014年第2期264-276,共13页分子植物（英文版）

摘　　要：Cysteine occupies a central position in plant metabolism because it is a reduced sulfur donor moleculeinvolved in the synthesis of essential biomolecules and defense compounds. Moreover, cysteine per se and its deriva-tive molecules play roles in the redox signaling of processes occurring in various cellular compartments. Cysteine issynthesized during the sulfate assimilation pathway via the incorporation of sulfide to O-acetylserine, catalyzed byO-acetylserine（thiol）lyase （OASTL）. Plant cells contain OASTLs in the mitochondria, chloroplasts, and cytosol, resultingin a complex array of isoforms and subcellular cysteine pools, in recent years, significant progress has been made inArabidopsis, in determining the specific roles of the OASTLs and the metabolites produced by them. Thus, the dis-covery of novel enzymatic activities of the less-abundant, like DES1 with L-cysteine desulfhydrase activity and SCSwith S-sulfocysteine synthase activity, has provided new perspectives on their roles, besides their metabolic functions.Thereby, the research has been demonstrated that cytosolic sulfide and chloroplastic S-sulfocysteine act as signalingmolecules regulating autophagy and protecting the photosystems, respectively. In the cytosol, cysteine plays an essentialrole in plant immunity; in the mitochondria, this molecule plays a central role in the detoxification of cyanide, which isessential for root hair development and plant responses to pathogens.

关 键 词：β-cyanoalanine SYNTHASE CYSTEINE desulfhydrase cyanide O-acetylserine(thiol)lyase PLANT development PLANT immunity redox signaling S-sulfocysteine SYNTHASE stress sulfide 

分 类 号：Q94[生物学—植物学]